Sucrose-induced analgesia is related to sweet preferences in children but not adults

The efficacy of sweet solutions on dental injection related pain: a systematic review of randomized controlled trials

Oral flavored solutions are effective for pain management. The intraoral application of sweet solutions at the injection site or on the tongue before local anesthetic administration leads to lower self-perceived pain than any other intervention. This systematic review aimed to evaluate the effect of sweet taste on injection pain in patients undergoing dental procedures. This systematic review was registered in the International Prospective Register of Systematic Reviews (PROSPERO) under registration number CRD42024571962 and followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). An initial electronic search without a time limit up to September 2024 revealed 1,087 studies from indexed databases (PubMed, Scopus, Embase, Cochrane, and Web of Science). The Cochrane Bias Assessment Tool was used to evaluate the risk of bias. After eliminating duplicate and automated records, 103 studies were screened for inclusion. After reviewing the titles and abstracts and assessing the eligibility of the studies, three were excluded and eight RCTs were considered appropriate for inclusion and analysis. This review highlights that all the included studies reported significantly reduced pain perception after sweet solutions, regardless of the specific type or concentration.

Efficacy of administering a sugar-free flavor before dental injections on pain perception in children: A split-mouth randomized crossover clinical trial

BACKGROUND

Sweet taste administration before dental injections helps to control associated pain in children.

AIM

To evaluate the efficacy of using a sugar-free flavor on pain perception during dental injections.

DESIGN

Children (n = 84) aged 4-9 (mean 6.71 ± 1.55) years who required buccal infiltration bilaterally participated in this split-mouth randomized crossover study. On the test side (flavor visit), infiltration injections were applied after receiving a sugar-free flavor. On the control side (no flavor visit), sterile water was administered. Demographic characteristics, body mass index (BMI), and sweet taste preference (STP) were recorded. Pain perception during injection was measured using heart rate (HR), sound, eyes, and motor (SEM) scale, and Wong-Baker Faces pain scale (WBFPS).

RESULTS

Most children had healthy weight (72.6%) and equal STP (32.1%). In the test side, mean HR during injection, HR differences before and during injection, and SEM scores were significantly lower (p < .001, for all). There was no significant difference in the WBFPS between both visits. Flavor had a significant effect on pain reduction (p = .001 for HR, p = .000 for SEM), whereas age, gender, BMI, STP, and treatment side did not. Treatment sequence had a significant effect on total SEM scores (p = .021); children who received the flavor during their first visit had lower SEM scores.

CONCLUSION

Using a sugar-free flavor before dental injections helps in reducing associated pain in children.

Efficacy of sucrose application in minimizing pain perception related to dental injection in children aged 3 to 9 years: a randomized control trial

Background

Dental fear and anxiety are significant challenges in managing behavior in children. Oral administration of sucrose or sweet-tasting solutions has shown effectiveness in reducing procedural pain in infants and neonates. This study aimed to investigate whether pre-application of sucrose solution had an effect on minimizing pain perception during injection and to assess the potential impact of the child's age and sweet preference.

Methods

A randomized control clinical trial was conducted on 60 children aged 3-9 years requiring buccal infiltration injections. Following parental consent, demographic data of the children were recorded. Sweet preferences was assessed using a modified forced-choice test. Children were equally and randomly allocated into study (sucrose) and control groups using a lottery method. Sucrose solution or distilled water, respectively, was applied to the lateral surface of the tongue for 2 min. Topical anesthetic was applied at the site of injection, followed by local anesthesia administration. The children rinsed their mouths thrice with water immediately after anesthetic injection. A video was recorded during injection which was then scored by three blinded examiners on the Sound Eye Motor (SEM) scale. The children also self-evaluated using Wong-Baker Faces Pain Rating Scale (WBFPS).

Results

The mean SEM scores and WBFPS scores were analyzed using the Kruskall-Wallis test. The mean SEM score in the study group was 1.37 ± 0.61, compared to 3.17 ± 0.87 in the control group, showing a statistically significant difference (P < 0.001). Mean pain scores assessed by WBFPS in the study group were 0.60 ± 1.4, while in the control group, they were 6.27 ± 2.33, also showing a statistically significant difference (P < 0.001). Children with a sweet preference demonstrated a subjective reduction in pain perception.

Conclusion

Application of sucrose before dental injections in children helps to minimize pain upon injection across all age groups.

Jelly snakes to reduce early postoperative vomiting in children after adenotonsillectomy: The randomized controlled snakes trial

BACKGROUND

Despite the use of dual antiemetic agents, postoperative nausea and vomiting (PONV) occurs in an unacceptably large number of patients post-tonsillectomy. There has been increased interest in alternative and non-pharmacological treatments for PONV e.g., chewing gum. We investigated if chewing a large confectionary jelly snake had prophylactic antiemetic effects postoperatively in young children.

METHODS

Prospective, open-label randomised controlled trial of 240 patients, 2-16 years. Patients administered a confectionary jelly snake to chew postoperatively were compared with a control group. The primary outcome was the number of episodes of vomiting within 6 h of the operation on an intention-to-treat basis.

SECONDARY OUTCOMES

incidence of nausea, vomiting at 6 and 24 h, rescue antiemetic use, acceptability, delayed discharge.

RESULTS

233 patients were randomised to receive the confectionary snake (snake group, 118) or standard care (control group, 115). The number of vomiting episodes in 6 h was similar between groups on an intention-to-treat basis, with 39 episodes across 22 (19%) patients in the control group and 31 across 19 (16%) patients in the snake group (p = 0.666). From post anaesthetic care unit until 24 h there was no difference in doses of antiemetics or delayed discharge due to PONV. A secondary as per protocol analysis did not change this result.

CONCLUSIONS

Chewing of confectionery jelly snakes within one hour of waking following adenotonsillectomy with vapour-maintained anaesthesia and two prophylactic antiemetics did not further reduce the incidence of early vomiting.

REGISTRATION

prospective registration at the Australia and New Zealand Clinical Trials Registry (ACTRN12618000637246).

Sucrose solution for alleviating needle pain during inferior alveolar nerve block in children aged 7-10 years: a randomized clinical trial

Background

Intraoral local anesthesia is essential for delivering dental care; however, injection of this local anesthetic is perceived as the most painful and distressing agent for children, parents, and healthcare providers. Reducing pain as much as possible is essential to ensure smooth subsequent treatment procedures, especially in pediatric dentistry. In clinical practice, oral sucrose administration has been reported to decrease the pain during heel lance and cold pressor tests in neonates and children. This study aimed to determine whether the prior administration of a 30% sucrose solution reduced the pain related to inferior alveolar nerve block in children.

Methods

A total of 42 healthy children aged 7-10 years requiring dental treatment of mandibular molars involving inferior alveolar nerve block were recruited. The participants' demographic details were recorded, height and weight were measured, and the anesthetic injection was delivered after receiving the respective intraoral sucrose solution and distilled water by the intervention (group 1) and control (group 2) group participants for 2 min. The subjective pain perceived during injection was measured using an animated emoji scale. The pain scores between the groups were compared using the Mann-Whitney U test.

Results

The median pain score and range for the intervention and control groups were 4 (2 - 6) and 6 (4 - 8), respectively, and statistically significant differences (P < 0.001) were observed in the intervention group. Age, sex, height, and weight did not influence the analgesic effect of the sucrose solution.

Conclusion

Oral administration of sucrose may relieve pain associated with inferior alveolar nerve block in children.

Improving ambulance care for children suffering acute pain: a qualitative interview study

Background

Pain is a highly complex sensory and emotional experience. When a child suffers acute pain through illness or injury, they are often transported to hospital by ambulance. Pre-hospital pain management in children is poor, with 61% of children receiving suboptimal pain management. Consequences of poor pain management include the risk of developing post-traumatic stress disorder and altered pain perception. We aimed to identify clinicians’ perceptions of barriers, facilitators and potential improvements for the management of pre-hospital acute pain in children.

Methods

Qualitative face to face semi-structured recorded interviews were performed in one large UK ambulance service. Audio files were transcribed verbatim with thematic analysis used to generate themes. NVivo 12 was used to support data analysis. Findings were combined with existing evidence to generate a driver diagram.

Results

Twelve ambulance clinicians participated, including 9 registered paramedics and 3 emergency medical technicians. Median (IQR) age was 43.50 (41.50, 45.75) years, 58% were male, median (IQR) experience was 12 (4.25, 15.50) years and 58% were parents. Several themes relating to barriers and facilitators were identified, including physical, emotional, social, organisational, environmental, management, knowledge and experience. Improvement themes were identified relating to management, organisation and education. These data were combined to create a driver diagram; the three primary drivers were 1) explore methods to increase rates of analgesic administration, including utilising intranasal or inhaled routes; 2) reduce fear and anxiety in children, by using child friendly uniform, additional non-pharmacological techniques and more public interaction and 3) reduce fear and anxiety in clinicians, by enhancing training and optimising crew mix.

Conclusions

The quality of care that children receive for acute pain in the ambulance service may be improved by increasing rates of analgesic administration and reducing the fear and anxiety experienced by children and clinicians. Future research involving children and parents would be useful to determine the most important outcome measures and facilitate intervention development.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12873-022-00648-y.

Understanding sweet-liking phenotypes and their implications for obesity: Narrative review and future directions

Building on a series of recent studies that challenge the universality of sweet liking, here we review the evidence for multiple sweet-liking phenotypes which strongly suggest, humans fall into three hedonic response patterns: extreme sweet likers (ESL), where liking increases with sweetness, moderate sweet likers (MSL), who like moderate but not intense sweetness, and sweet dislikers (SD), who show increasing aversion as sweetness increases. This review contrasts how these phenotypes differ in body size and composition, dietary intake and behavioural measures to test the widely held view that sweet liking may be a key driver of obesity. Apart from increased consumption of sugar-sweetened beverages in ESL, we found no clear evidence that sweet liking was associated with obesity and actually found some evidence that SD, rather than ESL, may have slightly higher body fat. We conclude that ESL may have heightened awareness of internal appetite cues that could protect against overconsumption and increased sensitivity to wider reward. We note many gaps in knowledge and the need for future studies to contrast these phenotypes in terms of genetics, neural processing of reward and broader measures of behaviour. There is also the need for more extensive longitudinal studies to determine the extent to which these phenotypes are modified by exposure to sweet stimuli in the context of the obesogenic environment.

The efficacy of administrating a sweet-tasting solution for reducing the pain related to dental injections in children: A randomized controlled trial

BACKGROUND

Anaesthetic injections are an unpleasant experience for children in the dental office. Oral intake of sweet substances by newborns has been shown to be effective in reducing pain.

AIM

The purpose of this study was to determine whether a prior administration of a sweet-tasting solution has an effect on dental injection pain.

DESIGN

A total of 56 healthy children needing bilateral maxillary primary canine extraction were included in this split-mouth randomized clinical trial. In the test side, dental injection (local infiltration) was applied after the patient received a sweet-tasting solution, while in the control side sterile water was administered. The patients' demographic characteristics, body mass index (BMI), and sweet taste preference were recorded. Pain perception during injection was measured using visual analogue scale (VAS) and sound, eye, body movement (SEM).

RESULTS

Mean VAS (28.30 ± 6.43) and SEM (2.14 ± 0.78) in the test side were lower than the control side (45.80 ± 7.17 and 2.95 ± 1.00). It was shown that higher BMI was associated with reduction in the analgesic effect, while the individual's tendency to sweetness increased pain reduction.

CONCLUSIONS

Sweet taste administration before dental injections in children helps to control the associated pain. This effect is influenced by the individual's sweet taste tendency and BMI.

Pain, Smell, and Taste in Adults: A Narrative Review of Multisensory Perception and Interaction

Every day our sensory systems perceive and integrate a variety of stimuli containing information vital for our survival. Pain acts as a protective warning system, eliciting a response to remove harmful stimuli; it may also be a symptom of an illness or present as a disease itself. There is a growing need for additional pain-relieving therapies involving the multisensory integration of smell and taste in pain modulation, an approach that may provide new strategies for the treatment and management of pain. While pain, smell, and taste share common features and are strongly linked to emotion and cognition, their interaction has been poorly explored. In this review, we provide an overview of the literature on pain modulation by olfactory and gustatory substances. It includes adult human studies investigating measures of pain threshold, tolerance, intensity, and/or unpleasantness. Due to the limited number of studies currently available, we have structured this review as a narrative in which we comment on experimentally induced and clinical pain separately on pain–smell and pain–taste interaction. Inconsistent study findings notwithstanding, pain, smell, and taste seem to interact at both the behavioral and the neural levels. Pain intensity and unpleasantness seem to be affected more by olfactory substances, whereas pain threshold and tolerance are influenced by gustatory substances. Few pilot studies to date have investigated these effects in clinical populations. While the current results are promising for the future, more evidence is needed to elucidate the link between the chemical senses and pain. Doing so has the potential to improve and develop novel options for pain treatment.

Smell and taste dissociations in the modulation of tonic pain perception induced by a capsaicin cream application

BACKGROUND

Pain is a subjective experience characterized by sensory (intensity) and emotional (unpleasantness) aspects. Although literature reports behavioural effects on pain due to smell and taste influence, to our knowledge the relationship between tonic pain induced by a capsaicin cream and these chemosensory systems has never been explored before. The aim of this study was to investigate the modulation of olfactory and gustatory substances having different valence on tonic pain perception mediated by a capsaicin cream application.

METHODS

Sixty healthy volunteers were included in two separated experiments (N = 30 smell; N = 30 taste) and underwent different valence smell and taste stimulations, while receiving painful stimuli. Perception of pain intensity (the sensory component) and unpleasantness (the affective component) was measured with a numerical rating scale, both during the two aforementioned experiments.

RESULTS

Pain unpleasantness rating showed differences only in the smell experiment between the two odourous conditions. In particular, pleasant odour induced lower ratings of pain unpleasantness, while no significant results were found for intensity. Regarding taste, we could not observe significant effects nor for pain unpleasantness or intensity.

CONCLUSIONS

These findings highlight the potential role of pleasant odours in influencing the affective aspects of pain perception induced by this kind of tonic pain. Such evidence might provide new insight for using chemosensory substances as analgesics for modulating the cognitive aspects of neuropathic pain.

SIGNIFICANCE

This work shows the effect of smell on the emotional component of tonic pain, experimentally induced by capsaicin cream application. Previous literature investigated tonic pain in interaction with smell and/or taste stimuli, but mainly with physical methods such as temperature. Our findings add new information in this field, contributing to a deeper insight on the role of olfaction on this particular kind of tonic pain perception. This approach could open to new investigations aimed to consider odours for pain management.

Sweet taste does not modulate pain perception in adult humans

Background: Sugar is routinely used to comfort neonates undergoing painful procedures, and animal studies have shown that sucrose increases the time to withdrawal from painful stimuli. However, there are no published studies examining the effects of sweet substances on heat pain thresholds and percept in adult humans. Methods: Healthy adult volunteers (n=27, aged 18-48 years) were recruited to a controlled, double-blind, randomised, cross-over study to characterise the effect of tasting solutions of equivalent sweetness (10% sucrose and 0.016% sucralose) on warm detection and heat pain thresholds and the percept ratings of painfully hot stimuli. The effect of anticipation of a sweet taste on heat pain threshold was also assessed. Results: Tasting either sucrose or sucralose had no significant effect on the percept of an individually titrated hot stimulus (54.5±4.2 and 54.9±3.2 vs 53.2±3.5 for water, 0-100 visual analogue scale), on the warm detection or heat pain threshold (43.3±0.8, 43.2±0.8 vs 43.0±0.8°C). Anticipation of a sweet substance similarly did not affect heat pain thresholds. Conclusions: Sucrose and sucralose solutions had no analgesic effect when assessed using heat detection thresholds and percept ratings of painfully hot stimuli despite being perceived as sweeter and more pleasant than water. These findings are in contrast to results reported from previous animal studies in which thermal analgesia from sweet solutions is robust. Given the ubiquitous availability of sugar rich drinks in the modern environment, the lack of observable effect may be due to an insufficient hedonic value of the test solutions when compared to the experience of a laboratory rodent. Alternatively, sweet tastes may have a specific effect on pain tolerance rather than the threshold and acute percept measures assayed in this study.

Sweet taste does not modulate pain perception in adult humans

Background: It is commonly observed that humans who are in pain or discomfort seek solace in the form of sweet foods and drinks. Sugar is routinely used to comfort neonates undergoing painful procedures, and animal studies have shown that sucrose increases the time to withdrawal from painful stimuli. However, there are no published studies examining the effects of sweet substances on heat pain thresholds and percept in adult humans. Methods: Healthy adult volunteers (n=27, aged 18-48 years) were recruited to a controlled, double-blind, randomised, cross-over study to characterise the effect of tasting solutions of equivalent sweetness (10% sucrose and 0.016% sucralose) on warm detection and heat pain thresholds and the percept ratings of painfully hot stimuli. The effect of anticipation of a sweet taste on heat pain threshold was also assessed. Results: Tasting either sucrose or sucralose had no significant effect on the percept of an individually titrated hot stimulus (54.5±4.2 and 54.9±3.2 vs 53.2±3.5 for water, 0-100 visual analogue scale), on the warm detection or heat pain threshold (43.3±0.8, 43.2±0.8 vs 43.0±0.8°C). Anticipation of a sweet substance similarly did not affect heat pain thresholds. Conclusions: Sucrose and sucralose solutions had no analgesic effect when assessed using heat detection thresholds and percept ratings of painfully hot stimuli despite being perceived as sweeter and more pleasant than water. These findings are in contrast to results reported from previous animal studies in which thermal analgesia from sweet solutions is robust. Given the ubiquitous availability of sugar rich drinks in the modern environment, the lack of observable effect may be due to an insufficient hedonic value of the test solutions when compared to the experience of a laboratory rodent. Alternatively, sweet tastes may have a specific effect on pain tolerance rather than the threshold and acute percept measures assayed in this study.

Determinants of Sweetness Preference: A Scoping Review of Human Studies

Factors associated with sweetness preference are multi-faceted and incredibly complex. A scoping review was undertaken to identify determinants of sweetness preference in humans. Using an online search tool, ProQuest ™, a total of 99 publications were identified and subsequently grouped into the following categories of determinants: Age, dietary factors, reproductive hormonal factors, body weight status, heritable, weight loss, sound, personality, ethnicity and lifestyle, previous exposure, disease, and 'other' determinants. Methodologies amongst studies were heterogenous in nature (e.g., there was variability across studies in the sweetness concentrations tested, the number of different sweetness concentrations used to assess sweetness preference, and the methods utilized to measure sweetness preference), rendering interpretation of overall findings challenging; however, for certain determinants, the evidence appeared to support predictive capacity of greater sweetness preference, such as age during certain life-stages (i.e., young and old), being in a hungry versus satiated state, and heritable factors (e.g., similar sweetness preferences amongst family members). Recommendations for the design of future studies on sweetness preference determinants are provided herein, including an "investigator checklist" of criteria to consider.

Greater analgesic effects of sucrose in the neonate predict greater weight gain to age 18 months

Intraoral sucrose has analgesic effects in the newborn period. The hedonic and analgesic effects of sucrose overlap and hedonic response to sweet food is associated with adiposity. The potential association between the analgesic effects of intraoral sucrose in the newborn period and subsequent weight gain has not been examined. Healthy, term newborns received 25% intraoral sucrose or water prior to metabolic screen heel stick. Negative affect, quiet alert behavior, and sleepiness were coded during heel stick. Weight and length were measured and z-score (WLZ) calculated at birth, 9, and 18 months. Mixed models tested associations of behavioral response to heel stick with WLZ trajectory among infants receiving sucrose (n = 154) versus water (n = 117). Among infants receiving sucrose prior to heel stick with birth WLZ ≥ the median, less negative affect and more sleepiness during heel stick were each associated with greater increases in WLZ. These associations were not present among infants receiving water only prior to heel stick. Greater analgesic effects of sucrose in the neonate were associated with greater future increases in WLZ, especially among infants with higher birth WLZ. Greater opioid-mediated newborn behavioral response to intraoral sucrose may be a marker for future obesity risk. CLINICAL TRIALS NUMBER: NCT02728141.

Taste and smell function in Wolfram syndrome

BACKGROUND

Wolfram syndrome is a rare genetic disease characterized by insulin-dependent diabetes, optic nerve atrophy, sensorineural hearing loss and neurodegeneration. Although olfactory dysfunction, a classical clinical marker of neurodegenerative processes, has been reported in Wolfram syndrome, its use as a clinical marker in Wolfram is limited due to data scarcity. In addition, it is unknown whether Wolfram syndrome affects the sense of taste.

METHODS

Smell and taste perception were assessed in participants with Wolfram syndrome (n = 40) who were 15.1 ± 6.0 years of age (range: 5.1-28.7 years) and two sex- and age-matched control groups: one group with type 1 diabetes mellitus (T1D; n = 25) and a healthy control group (HC; n = 29). Smell sensitivity was assessed by measuring n-butanol detection thresholds and smell identification by using the University of Pennsylvania Smell Identification Test (UPSIT). Taste function was assessed using NIH Toolbox, which includes the assessment of sucrose (sweet) taste preference, and perceived intensity of sucrose, sodium chloride (salty), and quinine hydrochloride (bitter) both in the tip of the tongue (regional test) and the whole mouth.

RESULTS

Smell sensitivity was not significantly different among groups; however, smell identification was impaired in Wolfram syndrome, as reflected by significantly lower UPSIT scores in Wolfram syndrome compared to HC and T1D (P < 0.001). Compared to participants in the control groups, participants with Wolfram syndrome had a blunted perception of sweetness and saltiness when taste stimuli were applied regionally (P < 0.05), but differences in perceived intensity were no longer significant among groups when taste stimuli were tasted with the whole mouth. Groups preferred similar sucrose concentrations.

CONCLUSION

Wolfram syndrome was associated with olfactory dysfunction. However, the olfactory dysfunction was qualitative (related to smell identification) and not secondary to olfactory insensitivity or diabetes, suggesting is arising from dysfunction in central olfactory brain regions. In contrast to olfaction, and despite decreased perception of taste intensity in the anterior tongue, the sense of taste was overall well-conserved in individuals with Wolfram syndrome. Future longitudinal studies of taste and smell perception in Wolfram syndrome will be important to determine the use of the chemical senses as clinical markers of disease progression.

Differential Cerebral Gustatory Responses to Sucrose, Aspartame, and Stevia Using Gustatory Evoked Potentials in Humans

Aspartame and Stevia are widely substituted for sugar. Little is known about cerebral activation in response to low-caloric sweeteners in comparison with high-caloric sugar, whereas these molecules lead to different metabolic effects. We aimed to compare gustatory evoked potentials (GEPs) obtained in response to sucrose solution in young, healthy subjects, with GEPs obtained in response to aspartame and Stevia. Twenty healthy volunteers were randomly stimulated with three solutions of similar intensities of sweetness: Sucrose 10 g/100 mL of water, aspartame 0.05 g/100 mL, and Stevia 0.03 g/100 mL. GEPs were recorded with EEG (Electroencephalogram) electrodes. Hedonic values of each solution were evaluated using the visual analog scale (VAS). The main result was that P1 latencies of GEPs were significantly shorter when subjects were stimulated by the sucrose solution than when they were stimulated by either the aspartame or the Stevia one. P1 latencies were also significantly shorter when subjects were stimulated by the aspartame solution than the Stevia one. No significant correlation was noted between GEP parameters and hedonic values marked by VAS. Although sucrose, aspartame, and Stevia lead to the same taste perception, cerebral activation by these three sweet solutions are different according to GEPs recording. Besides differences of taste receptors and cerebral areas activated by these substances, neural plasticity, and change in synaptic connections related to sweet innate preference and sweet conditioning, could be the best hypothesis to explain the differences in cerebral gustatory processing after sucrose and sweeteners activation.

Implications of a Retrospective Study on Weight-Based Risk for Post-Tonsillectomy Pain in Children

PURPOSE

The purpose was to examine if children experience weight-based risks for post-tonsillectomy pain (PTP) in the postanesthesia care unit (PACU).

DESIGN

This retrospective correlational cohort design included a sample of 180 children between the ages of 4 to 12 years who had tonsillectomy and adenoidectomy or tonsillectomy before August 2016; half were obese (OB) or overweight (OW).

METHODS

The sample was obtained from children who had surgery at a large pediatric hospital with an attached outpatient surgical center in North Texas. Children were defined as either OB and OW or non-OB and non-OW based on a cutoff of standardized body mass index z scores of 85th percentile and greater per the National Center for Health Statistics. Pain scores were obtained in the PACU after surgery. Early PTP was defined as the most severe pain experienced by a child in the first 15 minutes after extubation. Prolonged PTP was sustained and uncontrolled pain in the PACU.

FINDINGS

OB and OW status did not increase the likelihood of experiencing early PTP when examined by multiple logistic regression controlling for covariates (adjusted odds ratio, 1.391; P = .369). OB and OW status was associated with longer episodes of prolonged PTP (r_s[178] = 0.16; P = .03). OB and OW children were more likely to experience prolonged PTP in the PACU (χ²[1] = 8.353; P = .004), with these children experiencing an average PTP period twice as long as their peers.

CONCLUSIONS

OB and OW children did experience risk for prolonged PTP, averaging sustained pain for approximately twice as long as other children. The increased risk for prolonged PTP in OB and OW children occurred despite well-managed early PTP with rates that matched those of their peers. No weight-based risk for early PTP was observed. Further research is needed in the area of PTP management in OB and OW children.

Perception of phasic pain is modulated by smell and taste

BACKGROUND

Pain perception is a multimodal experience composed of sensory, emotional and cognitive dimensions. Accumulating evidence suggests that the chemical senses can influence pain perception, but their relation with phasic pain is still unknown. The aim of this study was to investigate the influence of smell and taste having different valence on phasic pain.

METHODS

Twenty-eight healthy volunteers received sweet, bitter and neutral odours or gustatory substances while receiving painful stimuli consisting of electrical shocks. Tactile threshold, pain threshold and pain tolerance were collected using the psychophysical method of limits at baseline and in association with smell and taste. Perception of pain intensity and unpleasantness was measured with a numerical rating scale.

RESULTS

Sweet smell induced lower ratings of pain intensity than bitter smell when stimuli were delivered at pain threshold. Sweet smell also induced lower ratings of pain unpleasantness than neutral smell when stimuli were delivered at pain tolerance. Sweet taste induced lower ratings of pain unpleasantness than bitter taste when stimuli were delivered at pain threshold. Conversely, pain threshold and pain tolerance per se were not affected by smell and taste.

CONCLUSIONS

These findings highlight an effect of sweet substances in reducing the subjective perception of pain intensity and unpleasantness associated to phasic pain.

SIGNIFICANCE

By demonstrating the link between smell, taste and phasic pain this study may have a translational impact in clinical conditions characterized by so-called shock-like pain, such as neuropathic pain.

Framework to Explain the Progression of Pain in Obese or Overweight Children Undergoing Tonsillectomy

An estimated 100,000 obese (OB) and overweight (OW) children undergo tonsillectomy each year in the United States. Pain management in this population is particularly challenging because of weight-based dosing, clinician fears, potential for airway obstruction, and genetic differences. A framework is proposed to explain factors involved in the post-tonsillectomy pain (PTP) experience in OB and OW children. The tonsillectomy, the body's inflammatory state, and mechanical stressors comprise influencing factors in PTP progression. Clinician-delivered medication doses, genetic variants of drug metabolism, and soothing factors serve as mediating factors in the progression of PTP. Postanesthesia care unit (PACU) nurses may use this framework to better understand PTP progression in OB and OW children. PACU nurses may manipulate certain mediating factors discussed in this framework to moderate PTP progression in OB and OW children. Researchers may use this framework to support future research to improve PTP management in OB and OW children.

Hedonic drinking engages a supraspinal inhibition of thermal nociception in adult rats

The taste of sucrose is commonly used to provide pain relief in newborn humans and is innately analgesic to neonatal rodents. In adulthood, sucrose remains a strong motivator to feed, even in potentially hazardous circumstances (ie, threat of tissue damage). However, the neurobiological mechanisms of this endogenous reward-pain interaction are unclear. We have developed a simple model of sucrose drinking-induced analgesia in Sprague-Dawley rats (6-10 weeks old) and have undertaken a behavioral and pharmacological characterization using the Hargreaves' test of hind-paw thermal sensitivity. Our results reveal an acute, potent, and robust inhibitory effect of sucrose drinking on thermal nociceptive behaviour that unlike the phenomenon in neonates is independent of endogenous opioid signalling and does not seem to operate through classical descending inhibition of the spinal cord circuitry. Experience of sucrose drinking had a conditioning effect whereby the apparent expectancy of sucrose enabled water alone (in euvolemic animals) to elicit a short-lasting placebo-like analgesia. Sweet taste alone, however, was insufficient to elicit analgesia in adult rats intraorally perfused with sucrose. Instead, the sucrose analgesia phenomenon only appeared after conditioning by oral perfusion in chronically cannulated animals. This sucrose analgesia was completely prevented by systemic dosing of the endocannabinoid CB1 receptor antagonist rimonabant. These results indicate the presence of an endogenous supraspinal analgesic circuit that is recruited by the context of rewarding drinking and is dependent on endocannabinoid signalling. We propose that this hedonic sucrose-drinking model may be useful for further investigation of the supraspinal control of pain by appetite and reward.

From biology to behavior: a cross-disciplinary seminar series surrounding added sugar and low-calorie sweetener consumption

INTRODUCTION

This report presents a synopsis of a three-part, cross-sector, seminar series held at the George Washington University (GWU) in Washington, DC from February-April, 2018. The overarching goal of the seminar series was to provide a neutral forum for diverse stakeholders to discuss and critically evaluate approaches to address added sugar intake, with a key focus on the role of low-calorie sweeteners (LCS).

METHODS

During three seminars, twelve speakers from academic institutions, federal agencies, non-profit organizations, and the food and beverage industries participated in six interactive panel discussions to address: 1) Do Farm Bill Policies Impact Population Sugar Intake? 2) What is the Impact of Sugar-sweetened Beverage (SSB) Taxes on Health and Business? 3) Is Sugar Addictive? 4) Product Reformulation Efforts: Progress, Challenges, and Concerns? 5) Low-calorie Sweeteners: Helpful or Harmful, and 6) Are Novel Sweeteners a Plausible Solution? Discussion of each topic involved brief 15-minute presentations from the speakers, which were followed by a 25-minute panel discussion moderated by GWU faculty members and addressed questions generated by the audience. Sessions were designed to represent opposing views and stimulate meaningful debate. Given the provocative nature of the seminar series, attendee questions were gathered anonymously using Pigeonhole™, an interactive, online, question and answer platform.

RESULTS

This report summarizes each presentation and recapitulates key perspectives offered by the speakers and moderators.

CONCLUSIONS

The seminar series set the foundation for robust cross-sector dialogue necessary to inform meaningful future research, and ultimately, effective policies for lowering added sugar intakes.

Role of Endocannabinoids on Sweet Taste Perception, Food Preference, and Obesity-related Disorders

The prevalence of obesity and obesity-related disorders such as type 2 diabetes (T2D) and metabolic syndrome has increased significantly in the past decades, reaching epidemic levels and therefore becoming a major health issue worldwide. Chronic overeating of highly palatable foods is one of the main responsible aspects behind overweight. Food choice is driven by food preference, which is influenced by environmental and internal factors, from availability to rewarding properties of food. Consequently, the acquisition of a dietary habit that may lead to metabolic alterations is the result of a learning process in which many variables take place. From genetics to socioeconomic status, the response to food and how this food affects energy metabolism is heavily influenced, even before birth. In this work, we review how food preference is acquired and established, particularly as regards sweet taste; towards which flavors and tastes we are positively predisposed by our genetic background, our early experience, further lifestyle, and our surroundings; and, especially, the role that the endocannabinoid system (ECS) plays in all of this. Ultimately, we try to summarize why this system is relevant for health purposes and how this is linked to important aspects of eating behavior, as its function as a modulator of energy homeostasis affects, and is affected by, physiological responses directly associated with obesity.

Toward Improving Medication Adherence: The Suppression of Bitter Taste in Edible Taste Films

Bitter taste is aversive to humans, and many oral medications exhibit a bitter taste. Bitter taste can be suppressed by the use of inhibitors or by masking agents such as sucralose. Another approach is to encapsulate bitter tasting compounds in order to delay their release. This delayed release can permit the prior release of bitter masking agents. Suppression of bitter taste was accomplished by encapsulating a bitter taste stimulus in erodible stearic acid microspheres, and embedding these 5 µmeter diameter microspheres in pullulan films that contain sucralose and peppermint oil as masking agents, along with an encapsulated masking agent (sucralose). Psychophysical tests demonstrated that films which encapsulated both quinine and sucralose produced a significant and continuous sweet percept when compared to films without sucralose microspheres. Films with both quinine and sucralose microspheres also produced positive hedonic scores that did not differ from control films that contained only sucralose microspheres or only empty (blank) microspheres. The encapsulation of bitter taste stimuli in lipid microspheres, and embedding these microspheres in rapidly dissolving edible taste films that contain masking agents in both the film base and in microspheres, is a promising approach for diminishing the bitter taste of drugs and related compounds.

Dosage form preference consultation study in children and young adults: paving the way for patient-centred and patient-informed dosage form development

Objectives

The current study aims to evaluate dosage form preferences in children and young adults together with identifying the key pragmatic dosage form characteristics that would enable appropriate formulation of orally disintegrating tablets (ODTs).

Methods

International, multisite, cross-sectional questionnaire of children and young adults aged from 6 to 18 years. Eligibility was based on age, ability to communicate and previous experience in taking medications. The study was carried out at three locations: the UK, Saudi Arabia and Jordan. The questionnaire instrument was designed for participant self-completion under supervision of the study team.

Results

104 questionnaires were completed by the study cohort (n=120, response rate 87%). Results showed that ODTs were the most preferred oral dosage forms (58%) followed by liquids (20%), tablets (12%) and capsules (11%). The preferred colours were pink or white while the preferred size was small (<8 mm) with a round shape. With regard to flavour, strawberry was the most preferred (30.8%), while orange was the least preferred (5.8%). The results also showed that the most important physical characteristics of ODTs were disintegration time followed by taste, size and flavour, respectively.

Conclusions

The results of our study support the WHO's claim for a shift of paradigm from liquid towards ODTs dosage forms for drug administration to young children older than 6 years. Data from this study will also equip formulators to prioritise development of key physical/performance attributes within the delivery system.

Personal Variation in Preference for Sweetness: Effects of Age and Obesity

BACKGROUND

Use of nonnutritive sweeteners (NNSs), which provide sweet taste with few to no calories, has increased, but data on whether children's hedonic responses to NNSs differ from nutritive sugars or from adults' hedonic responses are limited.

METHODS

Most preferred levels of sucrose and the NNS sucralose were determined via a forced-choice tracking procedure in 48 children, 7-14 years (mean = 10 years), and 34 adults. Each participant also rated the liking of these taste stimuli, as well as varying concentrations of aspartame on 3- and 5-point facial hedonic scales. Anthropometric measures were obtained, and motives for palatable food intake were assessed with the Palatable Eating Motives Scale (PEMS, adults) and Kids PEMS.

RESULTS

While use of the 3-point scale showed no age-related differences in liking of sweeteners, the 5-point scale showed that more children than adults liked higher concentrations of sucrose, sucralose, and aspartame, and the tracking procedure showed that children most preferred higher concentrations of sucrose and sucralose than adults. Regardless of age, sweet preference did not differ between obese and nonobese participants and showed no association with motives for eating palatable foods. Children's body mass index z-scores were positively associated with social and conformity motive scores for eating palatable foods.

CONCLUSION

Research should move beyond measures of variation in sweet taste hedonics to include identifying motives, and the physiological and psychological consequences of eating sweets, to shed light on what children are more vulnerable to develop unfavorable eating habits, increasing risk for obesity, and other diseases.

Sucrose and naltrexone prevent increased pain sensitivity and impaired long-term memory induced by repetitive neonatal noxious stimulation: Role of BDNF and β-endorphin

Pain in neonates is associated with short and long-term adverse outcomes. Data demonstrated that long-term consequences of untreated pain are linked to the plasticity of the neonate's brain. Sucrose is effective and safe for reducing painful procedures from single events. However, the mechanism of sucrose-induced analgesia is not fully understood. The role of the opioid system in this analgesia using the opioid receptor antagonist Naltrexone was investigated, plus the long-term effects on learning and memory formation during adulthood. Pain was induced in rat pups via needle pricks of the paws. Sucrose solution and/or naltrexone were administered before the pricks. All treatments started on day one of birth and continued for two weeks. At the end of 8weeks, behavioral studies were conducted to test spatial learning and memory using radial arm water maze (RAWM), and pain threshold via foot-withdrawal response to a hot plate. The hippocampus was dissected; levels of brain derived neurotrophic factor (BDNF) and endorphins were assessed using ELISA. Acute repetitive neonatal pain increased pain sensitivity later in life, while naltrexone with sucrose decreased pain sensitivity. Naltrexone and/or sucrose prevented neonatal pain induced impairment of long-term memory, while neonatal pain decreased levels of BDNF in the hippocampus; this decrease was averted by sucrose and naltrexone. Sucrose with naltrexone significantly increased β-endorphin levels in noxiously stimulated rats. In conclusion, naltrexone and sucrose can reverse increased pain sensitivity and impaired long-term memory induced by acute repetitive neonatal pain probably by normalizing BDNF expression and increasing β-endorphin levels.

Biological control of appetite: A daunting complexity

OBJECTIVE

This review summarizes a portion of the discussions of an NIH Workshop (Bethesda, MD, 2015) titled "Self-Regulation of Appetite-It's Complicated," which focused on the biological aspects of appetite regulation.

METHODS

This review summarizes the key biological inputs of appetite regulation and their implications for body weight regulation.

RESULTS

These discussions offer an update of the long-held, rigid perspective of an "adipocentric" biological control, taking a broader view that also includes important inputs from the digestive tract, from lean mass, and from the chemical sensory systems underlying taste and smell. It is only beginning to be understood how these biological systems are integrated and how this integrated input influences appetite and food eating behaviors. The relevance of these biological inputs was discussed primarily in the context of obesity and the problem of weight regain, touching on topics related to the biological predisposition for obesity and the impact that obesity treatments (dieting, exercise, bariatric surgery, etc.) might have on appetite and weight loss maintenance. Finally considered is a common theme that pervaded the workshop discussions, which was individual variability.

CONCLUSIONS

It is this individual variability in the predisposition for obesity and in the biological response to weight loss that makes the biological component of appetite regulation so complicated. When this individual biological variability is placed in the context of the diverse environmental and behavioral pressures that also influence food eating behaviors, it is easy to appreciate the daunting complexities that arise with the self-regulation of appetite.

Tobacco industry use of flavourings to promote smokeless tobacco products

BACKGROUND

While fruit, candy and alcohol characterising flavours are not allowed in cigarettes in the USA, other flavoured tobacco products such as smokeless tobacco (ST) continue to be sold. We investigated tobacco manufacturers' use of flavoured additives in ST products, the target audience(s) for flavoured products, and marketing strategies promoting products by emphasising their flavour.

METHODS

Qualitative analysis of internal tobacco industry documents triangulated with data from national newspaper articles, trade press and internet.

RESULTS

Internally, flavoured products have been consistently associated with young and inexperienced tobacco users. Internal studies confirmed that candy-like sweeter milder flavours (eg, mint, fruit) could increase appeal to starters by evoking a perception of mildness, blinding the strong tobacco taste and unpleasant mouth feel; or by modifying nicotine delivery by affecting product pH.

DISCUSSION

Similar to cigarettes, flavoured ST is likely to encourage novices to start using tobacco, and regulations limiting or eliminating flavours in cigarettes should be extended to include flavoured ST products.

Why do we like sweet taste: A bitter tale?

Sweet is widely considered to be one of a small number of basic or primary taste qualities. Liking for sweet tasting substances is innate, although postnatal experiences can shape responses. The power of sweet taste to induce consumption and to motivate behavior is profound, suggesting the importance of this sense for many species. Most investigators presume that the ability to identify sweet molecules through the sense of taste evolved to allow organisms to detect sources of readily available glucose from plants. Perhaps the best evidence supporting this presumption are recent discoveries in comparative biology demonstrating that species in the order Carnivora that do not consume plants also do not perceive sweet taste due to the pseudogenization of a component of the primary sweet taste receptor. However, arguing against this idea is the observation that the sweetness of a plant, or the amount of easily metabolizable sugars contained in the plant, provides little quantitative indication of the plant's energy or broadly conceived food value. Here it is suggested that the perceptual ratio of sweet taste to bitter taste (a signal for toxicity) may be a better gauge of a plant's broadly conceived food value than sweetness alone and that it is this ratio that helps guide selection or rejection of a potential plant food.

The development of sweet taste: From biology to hedonics

From the age of 2 years, an American child is more likely to consume a sugar-sweetened product than a fruit or vegetable on any given day-a troubling statistic, given that food preferences are established early in childhood, as well as the strong association between this dietary pattern and increased risk of developing a number of chronic diseases. Here, we review the ontogeny and biopsychology of sweet taste, highlighting how a biological drive to prefer sweetness at high concentrations during childhood, which would have conferred an advantage in environments of scarcity, now predisposes children to overconsume all that is sweet in a modern food system replete with added sugars. We review the power of sweet taste to blunt expressions of pain and mask bad tastes in foods as well as factors that predispose some to consume high-sugar diets, including experiential learning and taste preferences driven in part by genetics. Understanding children's unique vulnerability to our current food environment, rich in both nutritive and nonnutritive sweeteners, is highlighted as a priority for future research to develop evidence-based strategies to help establish healthy dietary behaviors early in life.

Vegetable and Fruit Acceptance during Infancy: Impact of Ontogeny, Genetics, and Early Experiences

Many of the chronic illnesses that plague modern society derive in large part from poor food choices. Thus, it is not surprising that the Dietary Guidelines for Americans, aimed at the population ≥2 y of age, recommends limiting consumption of salt, fat, and simple sugars, all of which have sensory properties that we humans find particularly palatable, and increasing the variety and contribution of fruits and vegetables in the diet, to promote health and prevent disease. Similar recommendations may soon be targeted at even younger Americans: the B-24 Project, led by the US Department of Health and Human Services and the USDA, is currently evaluating evidence to include infants and children from birth to 2 y of age in the dietary guidelines. This article reviews the underinvestigated behavioral phenomena surrounding how to introduce vegetables and fruits into infants' diets, for which there is much medical lore but, to our knowledge, little evidence-based research. Because the chemical senses are the major determinants of whether young children will accept a food (e.g., they eat only what they like), these senses take on even greater importance in understanding the bases for food choices in children. We focus on early life, in contrast with many other studies that attempt to modify food habits in older children and thus may miss sensitive periods that modulate long-term acceptance. Our review also takes into consideration ontogeny and sources of individual differences in taste perception, in particular, the role of genetic variation in bitter taste perception.

The sweetness and bitterness of childhood: Insights from basic research on taste preferences

In this article, we review findings from basic, experimental research on children that suggest that the liking of sweet and the dislike of bitter tastes reflect children's basic biology. Children are born preferring sweet tastes, which attract them to mother's milk and even act as an analgesic. They prefer higher levels of sweet than do adults, with preferences declining to adult levels during middle to late adolescence, which coincides with the cessation of physical growth. The level of sweetness most preferred by children has remained heightened relative to adults for nearly a decade, despite reductions in sugar, both consumed and in the food environment. In spite of these reductions, however, children's intake of sugar remains higher than that recommended by health organizations worldwide. In contrast to sweet taste, children dislike and reject bitter taste, which protects them from ingesting poisons. Although variation in bitter taste receptor genes such as TAS2R38 accounts for people's marked differences in perceptions of the same bitter-tasting compounds, basic research revealed that these genotype-phenotype relationships are modified with age, with children of the same genotype being more bitter sensitive than adults and the changeover occurring during mid-adolescence. This heightened bitter sensitivity is also evident in the taste of the foods (green vegetables) or medicines (liquid formulations of drugs) they dislike and reject. While bitter taste can be masked or blocked to varying degrees by sugars and salts, their efficacy in modulating bitterness is not only based on the type of bitter ligand but on the person's age. Children's heightened preference for sweet and dislike of bitter, though often detrimental in the modern food environment, reflects their basic biology. Increasing knowledge of individual variation in taste due to both age and genetics will shed light on potential strategies to promote healthier eating since chronic diseases derive in large part from poor food choice dictated by taste preferences, and will contribute to a new era of drug formulations designed especially for the taste palate of children.

Sweet tasting solutions for reduction of needle-related procedural pain in children aged one to 16 years

BACKGROUND

Extensive evidence exists showing analgesic effects of sweet solutions for newborns and infants. It is less certain if the same analgesic effects exist for children one year to 16 years of age. This is an updated version of the original Cochrane review published in Issue 10, 2011 (Harrison 2011) titled Sweet tasting solutions for reduction of needle-related procedural pain in children aged one to 16 years.

OBJECTIVES

To determine the efficacy of sweet tasting solutions or substances for reducing needle-related procedural pain in children beyond one year of age.

SEARCH METHODS

Searches were run to the end of June 2014. We searched the following databases: the Cochrane Central Register of Controlled Trials (CENTRAL), Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects (DARE), Cochrane Methodology Register, Health Technology Assessment, the NHS Economic Evaluation Database, MEDLINE, EMBASE, PsycINFO, and ACP Journal Club (all via OvidSP), and CINAH (via EBSCOhost). We applied no language restrictions.

SELECTION CRITERIA

Published or unpublished randomised controlled trials (RCT) in which children aged one year to 16 years, received a sweet tasting solution or substance for needle-related procedural pain. Control conditions included water, non-sweet tasting substances, pacifier, distraction, positioning/containment, breastfeeding, or no treatment.

DATA COLLECTION AND ANALYSIS

Outcome measures included crying duration, composite pain scores, physiological or behavioral pain indicators, self-report of pain or parental or healthcare professional-report of the child's pain. We reported mean differences (MD), weighted mean difference (WMD), or standardized mean difference (SMD) with 95% confidence intervals (CI) using fixed-effect or random-effects models as appropriate for continuous outcome measures. We reported risk ratio (RR), risk difference (RD), and the number needed to treat to benefit (NNTB) for dichotomous outcomes. We used the I(2) statistic to assess between-study heterogeneity.

MAIN RESULTS

We included one unpublished and seven published studies (total of 808 participants); four more studies and 478 more participants than the 2011 review. Six trials included young children aged one to four years receiving sucrose or candy lollypops for immunisation pain compared with water or no treatment. Usual care included topical anaesthetics, upright parental holding, and distraction. All studies were well designed blinded RCTs, however, five of the six studies had a high risk of bias based on small sample sizes.Two studies included school-aged children receiving sweet or unsweetened chewing gum before, or before and during, immunisation and blood collection. Both studies, conducted by the same author, had a high risk of bias based on small sample sizes.Results for the toddlers/pre-school children were conflicting. Duration of cry, using a random-effects model, was not significantly reduced by sweet taste (six trials, 520 children, WMD -15 seconds, 95% CI -54 to 24, I(2) = 94%).Composite pain score at time of first needle was reported in four studies (n = 121 children). The scores were not significantly different between the sucrose and control group (SMD -0.26, 95% CI -1.27 to 0.75, I(2) = 86%).A Children's Hospital of Eastern Ontario Pain Scale score > 4 was significantly less common in the sucrose group compared to the control group in one study (n = 472, RR 0.55, 95% CI 0.45 to 0.67; RD -0.29, 95% CI -0.37 to -0.20; NNTB 3, 95% CI 3 to 5; tests for heterogeneity not applicable.For school-aged children, chewing sweet gum before needle-related painful procedures (two studies, n = 111 children) or during the procedures (two studies, n = 103 children) did not significantly reduce pain scores. A comparison of the Faces Pain Scale scores in children chewing sweet gum before the procedures compared with scores of children chewing unsweetened gum revealed a WMD of -0.15 (95% CI -0.61 to 0.30). Similar results were found when comparing the chewing of sweet gum with unsweetened gum during the procedure (WMD 0.23, 95% CI -0.28 to 0.74). The Colored Analogue Scale for children chewing sweet gum compared to unsweetened gum before the procedure was not significantly different (WMD 0.24 (-0.69 to 1.18)) nor was it different when children chewed the gum during the procedure (WMD 0.86 (95% CI -0.12 to 1.83)). There was no heterogeneity for any of these analyses in school-aged children (I(2) = 0%).

AUTHORS' CONCLUSIONS

Based on the eight studies included in this systematic review update, two of which were subgroups of small numbers of eligible toddlers from larger studies, and three of which were pilot RCTs with small numbers of participants, there is insufficient evidence of the analgesic effects of sweet tasting solutions or substances during acutely painful procedures in young children between one and four years of age. Further rigorously conducted, adequately powered RCTs are warranted in this population. Based on the two studies by the same author, there was no evidence of analgesic effects of sweet taste in school-aged children. As there are other effective evidence-based strategies available to use in this age group, further trials are not warranted.Despite the addition of four studies in this review, conclusions have not changed since the last version of the review.

Disruption in the Relationship between Blood Pressure and Salty Taste Thresholds among Overweight and Obese Children

BACKGROUND

Prevalence of high blood pressure among American children has increased over the past 2 decades, due in part to increasing rates of obesity and excessive dietary salt intake.

OBJECTIVE

We tested the hypothesis that the relationships among blood pressure, salty taste sensitivity, and salt intake differ between normal-weight and overweight/obese children.

DESIGN

In an observational study, sodium chloride (NaCl) and monosodium glutamate (MSG) taste detection thresholds were measured using the Monell two-alternative, forced-choice, paired-comparison tracking method. Weight and blood pressure were measured, and salt intake was determined by 24-hour dietary recall.

PARTICIPANTS/SETTING

Children aged 8 to 14 years (N=97; 52% overweight or obese) from the Philadelphia, PA, area completed anthropometric and blood pressure measurements; 97% completed one or both thresholds. Seventy-six percent provided valid dietary recall data. Testing was completed between December 2011 and August 2012.

MAIN OUTCOME MEASURES

NaCl and MSG detection thresholds, blood pressure, and dietary salt intake.

STATISTICAL ANALYSES

Outcome measures were compared between normal-weight and overweight/obese children with t tests. Relationships among outcome measures within groups were examined with Pearson correlations, and multiple regression analysis was used to examine the relationship between blood pressure and thresholds, controlling for age, body mass index z score, and dietary salt intake.

RESULTS

NaCl and MSG thresholds were positively correlated (r[71]=0.30; P=0.01) and did not differ between body weight groups (P>0.20). Controlling for age, body mass index z score, and salt intake, systolic blood pressure was associated with NaCl thresholds among normal-weight children (P=0.01), but not among overweight/obese children. All children consumed excess salt (>8 g/day). Grain and meat products were the primary source of dietary sodium.

CONCLUSIONS

The apparent disruption in the relationship between salty taste response and blood pressure among overweight/obese children suggests the relationship may be influenced by body weight. Further research is warranted to explore this relationship as a potential measure to prevent development of hypertension.

Stress, behavior, and biology: risk factors for cardiovascular diseases in youth

Psychological stress reactivity is associated with atherogenesis in youth. The novel hypothesis is that stress promotes atherogenic behaviors, including snacking on energy-dense food and reducing physical activity, and increases adiposity. Stress also increases systolic blood pressure cardiovascular reactivity, which also may be atherogenic. Exercise dampens stress reactivity and may be one mechanism by which it protects against the development of cardiovascular diseases.

The brain-gut axis in health and disease

The interaction between the brain and the gut has been recognized for many centuries. This bidirectional interaction occurs via neural, immunological and hormonal routes, and is important not only in normal gastrointestinal function but also plays a significant role in shaping higher cognitive function such as our feelings and our subconscious decision-making. Therefore, it remains unsurprising that perturbations in normal signalling have been associated with a multitude of disorders, including inflammatory and functional gastrointestinal disorders, and eating disorders.

Effect of negative emotions evoked by light, noise and taste on trigeminal thermal sensitivity

Background

Patients with migraine often have impaired somatosensory function and experience headache attacks triggered by exogenous stimulus, such as light, sound or taste. This study aimed to assess the influence of three controlled conditioning stimuli (visual, auditory and gustatory stimuli and combined stimuli) on affective state and thermal sensitivity in healthy human participants.

Methods

All participants attended four experimental sessions with visual, auditory and gustatory conditioning stimuli and combination of all stimuli, in a randomized sequence. In each session, the somatosensory sensitivity was tested in the perioral region with use of thermal stimuli with and without the conditioning stimuli. Positive and Negative Affect States (PANAS) were assessed before and after the tests. Subject based ratings of the conditioning and test stimuli in addition to skin temperature and heart rate as indicators of arousal responses were collected in real time during the tests.

Results

The three conditioning stimuli all induced significant increases in negative PANAS scores (paired t-test, P ≤0.016). Compared with baseline, the increases were in a near dose-dependent manner during visual and auditory conditioning stimulation. No significant effects of any single conditioning stimuli were observed on trigeminal thermal sensitivity (P ≥0.051) or arousal parameters (P ≥0.057). The effects of combined conditioning stimuli on subjective ratings (P ≤0.038) and negative affect (P = 0.011) were stronger than those of single stimuli.

Conclusions

All three conditioning stimuli provided a simple way to evoke a negative affective state without physical arousal or influence on trigeminal thermal sensitivity. Multisensory conditioning had stronger effects but also failed to modulate thermal sensitivity, suggesting that so-called exogenous trigger stimuli e.g. bright light, noise, unpleasant taste in patients with migraine may require a predisposed or sensitized nervous system.

Oral sucrose administration to reduce pain response during immunization in 16-19-month infants: a randomized, placebo-controlled trial

Although the analgesic effect of sucrose on newborns is well established, little is known about whether these solutions are effective in reducing procedural pain in infants beyond the newborn period. The purpose of this study was to determine the effect of sucrose solution given orally on infant crying times and measure the distress in a 16-19-month age group. A total of 537 healthy, 16-19-month-old infants attending for their immunizations with intramuscular diphtheria, tetanus, and acellular pertussis (DTaP)/Haemophilus influenza type b/IPV (along with oral polio vaccination (OPV)), intramuscular pneumococcus and intramuscular hepatitis A were randomized to receive 2 mL of a 75 % sucrose solution, a 25 % sucrose solution or sterile water 2 min before injections. Infants receiving a 75 % sucrose solution had significantly reduced total crying times and Children's Hospital of Eastern Ontario Pain Scale scores (CHEOPS) compared with infants in the control and 25 % sucrose solution groups (p < 0.001).

CONCLUSION

Sucrose solution reduces infant distress and is safe and clinically useful even for 16-19-month-old infants.

Intact Hedonic Responses to Sweet Tastes in Autism Spectrum Disorder

The Sweet Taste Test (STT) is a standardized measure designed to index the ability to detect differences in sweet tastes (sweet taste sensitivity) and hedonic responses to sweet tastes (sweet taste liking). Profiles of response on the STT suggest enhanced hedonic responses to sweet tastes in psychiatric disorders characterized by dysfunctional reward processing systems, including binge-eating disorders and substance use disorders, and a putative mechanism governing STT responses is the brain opioid system. The present study examined STT responses in 20 adults with autism spectrum disorder (ASD) and 38 healthy control adults. There were no differences in sweet taste sensitivity or hedonic response to sweet tastes between the ASD and control groups. Within the ASD sample, ASD symptom severity was associated with sweet taste sensitivity, but not hedonic response to sweet taste. Results may ultimately shed light on brain opioid system functioning in ASD.

Ontogeny of taste preferences: basic biology and implications for health

Health initiatives address childhood obesity in part by encouraging good nutrition early in life. This review highlights the science that shows that children naturally prefer higher levels of sweet and salty tastes and reject lower levels of bitter tastes than do adults. Thus, their basic biology does not predispose them to favor the recommended low-sugar, low-sodium, vegetable-rich diets and makes them especially vulnerable to our current food environment of foods high in salt and refined sugars. The good news is that sensory experiences, beginning early in life, can shape preferences. Mothers who consume diets rich in healthy foods can get children off to a good start because flavors are transmitted from the maternal diet to amniotic fluid and mother's milk, and breastfed infants are more accepting of these flavors. In contrast, infants fed formula learn to prefer its unique flavor profile and may have more difficulty initially accepting flavors not found in formula, such as those of fruit and vegetables. Regardless of early feeding mode, infants can learn through repeated exposure and dietary variety if caregivers focus on the child's willingness to consume a food and not just the facial expressions made during feeding. In addition, providing complementary foods low in salt and sugars may help protect the developing child from excess intake later in life. Early-life experiences with healthy tastes and flavors may go a long way toward promoting healthy eating, which could have a significant impact in addressing the many chronic illnesses associated with poor food choice.

Early influences on the development of food preferences

The ability to perceive flavors begins in utero with the development and early functioning of the gustatory and olfactory systems. Because both amniotic fluid and breast milk contain molecules derived from the mother's diet, learning about flavors in foods begins in the womb and during early infancy. This early experience serves as the foundation for the continuing development of food preferences across the lifespan, and is shaped by the interplay of biological, social, and environmental factors. Shortly after birth, young infants show characteristic taste preferences: sweet and umami elicit positive responses; bitter and sour elicit negative responses. These taste preferences may reflect a biological drive towards foods that are calorie- and protein-dense and an aversion to foods that are poisonous or toxic. Early likes and dislikes are influenced by these innate preferences, but are also modifiable. Repeated exposure to novel or disliked foods that occurs in a positive, supportive environment may promote the acceptance of and eventually a preference for those foods. Alternatively, children who are pressured to eat certain foods may show decreased preference for those foods later on. With increasing age, the influence of a number of factors, such as peers and food availability, continue to mold food preferences and eating behaviors.

Problem behavior, victimization, and soda intake in high school students

OBJECTIVE

To examine associations of problem behaviors and victimization with nondiet soda intake among a national sample of 16,188 US high school students.

METHODS

We used the 2009 national Youth Risk Behavior Survey. The outcome measure was daily nondiet soda intake.

RESULTS

Smoking, having any sex partners, not always wearing a seat belt, being bullied/threatened/injured on school property, and being physically hurt by their boyfriend/girlfriend were significantly associated with daily nondiet soda intake after adjustment for age, sex, race/ethnicity, and weight status.

CONCLUSIONS

Our findings suggest a need to examine why nondiet soda intake is associated with these behaviors to understand potential mechanisms.

Active and passive distraction in children undergoing wound dressings

The aim of this study was to test how distraction influences pain, distress and anxiety in children during wound care. Sixty participants aged 5-12 years were randomized to three groups: serious gaming, the use of lollipops and a control group. Self-reported pain, distress, anxiety and observed pain behaviour were recorded in conjunction with wound care. Serious gaming, an active distraction, reduced the observed pain behaviour and self-reported distress compared with the other groups. A sense of control and engagement in the distraction, together, may be the explanation for the different pain behaviours when children use serious gaming.

Differential effect of visual and gustatory stimuli on experimental jaw muscle pain

BACKGROUND

Emotions form an important component in the expression and manifestation of pain. This study tested whether emotionally loaded visual and gustatory conditioning stimuli could influence experimental jaw muscle pain.

PATIENTS AND METHODS

Thirty-one healthy subjects participated in this study. In two sessions, experimental jaw muscle pain was evoked by injection of hypertonic saline (HS) into the masseter muscle. In the first session, jaw muscle pain was conditioned by positive, negative or neutral pictures. In the next session, jaw muscle pain was conditioned by sweet, bitter or tasteless gelatine in the mouth. The subjects continuously rated pain intensity as well as mood and unpleasantness/pleasantness of the conditioning stimuli. As a control experiment, the same design was applied in eight subjects using painful thermal stimuli.

RESULTS

HS evoked moderate levels of pain in all subjects. During conditioning with negatively loaded pictures, HS-evoked pain was higher compared with neutral and positive pictures (p = 0.002). There was a significant correlation between negative emotional scores linked to the pictures and HS-evoked pain intensity (r = 0.404, p = 0.021). No effects on HS-evoked pain intensity were observed during positive pictures or during sweet or bitter gustatory stimuli. The latter may be due to failure of the gustatory stimuli to generate changes in emotional scores. No significant effects were observed on thermal pain sensitivity.

CONCLUSION

These results suggest that not all conditioning stimuli are potent modifiers of emotions, which seems to be a prerequisite for effects on muscle pain perception.

Lingual tactile acuity and food texture preferences among children and their mothers

Despite anecdotal reports of children being more sensitive to texture than adults, and of texture being one of the main drivers of food aversions, there is a paucity of scientific knowledge on the influence of texture perception on food choice in children. The primary goals of this study were to assess the use of a modified letter-identification task to study lingual tactile acuity, one aspect of oral sensitivity, in children and to examine age-related differences in sensitivity. The secondary goal was to explore whether lingual tactile acuity and age relate to various measures of food choice and preference. To this end, children 7-10 years old (31 girls, 21 boys) and their mothers were tested using identical procedures. To assess lingual tactile acuity, children and mothers were asked to use the tips of their tongues to identify raised alphabetical letters of varying size (2.5-8.0 mm) on Teflon strips. To relate lingual tactile acuity to food texture preferences, a forced-choice questionnaire assessed preferences for foods similar in flavor but different in texture (e.g., smooth versus crunchy peanut butter). Children were able to complete the lingual acuity task as well as their mothers and took less time to assess each letter stimulus (p < 0.001); however, there were no age-related differences in lingual acuity (p = 0.14). Age, but not lingual acuity, related to food texture preferences: mothers preferred harder foods (p < 0.001) and those containing more particles (p < 0.04) than did children, although children's preferences became more adult-like with increasing age. The availability of a rapid, child-friendly method for assessing oral sensitivity opens up new possibilities of examining differences in oral tactile perceptions across the life span. That food preferences changed with age and were not related to oral sensitivity underscores the fact that factors such as experience, culture and family food practices have a significant impact on children's food texture preferences.

Sweet taste and chorda tympani transection alter capsaicin-induced lingual pain perception in adult human subjects

Sweetness signals the nutritional value of food and may moreover be accompanied by a sensory suppression that leads to higher pain tolerance. This effect is well documented in infant rats and humans. However, it is still debated whether sensory suppression is also present in adult humans. Thus, we investigated the effects of sweet taste on the perception of the painful trigeminal stimulus capsaicin in two groups of healthy adult human subjects. A solution of 100 μM capsaicin was applied to the tip of the subject's tongues in order to stimulate trigeminal Aδ- and C-fiber nociceptors. When swallowed, 1M sucrose reduced the capsaicin-induced burning sensation by 29% (p ≤ 0.05) whereas a solution of similar taste intensity containing 1 μM quinine did not. Similarly, sucrose application to the frontal hemitongue suppressed the perception of the burning sensation induced by contralaterally applied capsaicin by 25% (p ≤ 0.01). We furthermore investigated the effects of documented unilateral transection of the chorda tympani nerve on capsaicin perception. In accordance with the ipsi-to-contralateral effect of sucrose on capsaicin perception in healthy subjects, hemiageusic subjects were more sensitive for capsaicin on the tongue contralateral to the taste nerve lesion (+38%; p ≤ 0.01). Taken together, these results argue I) for the existence of food intake-induced sensory suppression, if not analgesia, in adult humans and II) a centrally mediated suppression of trigeminal sensation by taste inputs that III) becomes disinhibited upon peripheral taste nerve lesion.

Sugaring the pill: ethics and uncertainties in the use of sucrose for newborn infants

Sucrose is widely used for the management of procedural pain in newborn infants, including capillary blood sampling, venepuncture, and vascular cannulation. Multiple randomized controlled trials have demonstrated that sweet-tasting solutions reduce behavioral responses to acute painful stimuli. It has been claimed that sucrose should be a standard of care in neonatal units and that further placebo-controlled trials of sucrose are unnecessary and unethical. However, recently published data cast doubt on the analgesic properties of sucrose. We review this new evidence and analyze the philosophical and ethical questions that it raises, including the "problem of other minds." Sugar may be better understood not as an analgesic, removing or relieving pain, but as a compensating pleasure. There is a need for further research on the mechanism of sucrose's effect on pain behavior and on the long-term effects of sucrose treatment. Such trials will require comparison with placebo or with other interventions. Given uncertainty about the benefit of sucrose, it may be wise to use alternative analgesics or nonpharmacological interventions where these are available and appropriate. Sucrose may not be the answer to procedural pain in newborns.