Effects on Growth of Smell and Taste of Milk During Tube Feeding of Preterm Infants: A Randomized Clinical Trial

The Effect of Olfactory Stimulation on Growth Parameters in Newborn Infants: A Systematic Review

Objective: Olfactory stimulation can be used for many purposes, such as providing comfort, improving sleep, and reducing pain in newborns. However, there are only a few studies in the literature examining the effect of olfactory stimulation on newborn growth. The aim of this study was to evaluate the effect of olfactory stimulation on growth parameters of newborns. Method: This systematic review used the PRISMA checklist. No date limitation was applied, and all studies were considered for inclusion. Pubmed, Web of Science, Scopus, and Medline databases were used for the search. Results: A total of 367 publications were found in the search. Eight studies that met the inclusion criteria were included in the study. The olfactory stimulations applied were maternal odor, maternal milk odor, cinnamon, aniseed, vanilla, and formula milk odors. Olfactory stimulation was found to have a positive effect on the weight gain of newborns in three of the eight studies, and maternal odor and maternal milk odor were used in these studies. In two of the three studies evaluating the effect of maternal odor and maternal milk olfactory stimulation on the height of newborns, the result was found to be significant. The effect of maternal milk olfactory stimulation on head circumference was found to be significant in one of the two studies. Conclusion and Recommendation: Maternal odorand maternal milk odor may have a positive effect on newborn growth parameters. Further studies on this subject are needed.

Effect of Smell and Taste of Milk on Feeding Parameters in Preterm Neonates: An Updated Meta-Analysis

Smell and taste sensations have been linked to positive outcomes in the feeding of premature infants, though the impact on the time required to transition to oral feeding remains unclear. This study aimed to evaluate the beneficial effects of smell and taste interventions on clinical outcomes in preterm infants. We conducted a search in PubMed, Scopus, Web of Science, and the Cochrane Central Register of Controlled Trials from inception through September 2024 for randomized controlled trials (RCTs) examining the effects of smell and taste on clinical outcomes in preterm infants with a gestational age of less than 34 weeks. The quality of the included studies was evaluated using the updated Cochrane's Risk of Bias tool (version 2). The primary outcome was the time required to achieve oral feeds. Secondary outcomes included the time to reach full enteral feeds, length of hospital stay, postmenstrual age, the need for parenteral nutrition, and the incidence of nosocomial infections. The outcomes were summarized as mean difference (MD) or odds ratio (OR) with 95% confidence intervals (CI) using a random-effects model. A total of 12 RCTs involving 1,638 preterm infants were included in the analysis. The results showed that smell and taste interventions significantly reduced the time needed to reach oral feeds (MD = -1.37 days, 95% CI [-2.26, -0.48], p < 0.001; I² = 42.15%) compared to no intervention. These findings were consistent across subgroup analyses based on birth weight at admission, type of exposure, and sample size. However, no significant differences were found for the other secondary outcomes. In conclusion, smell and taste interventions significantly reduced the time to reach oral feeds, with similar outcomes for other clinical measures compared to no intervention. These findings suggest that smell and taste interventions could be used in the care of preterm infants, with the need for large-volume RCTs and long-term assessments being warranted.

Effects of Gustatory and Olfactory Stimulation on Feeding Outcomes in Preterm Infants: A Systematic Review and Meta-Analysis

BACKGROUND

Few primary studies have examined the impact of olfactory and gustatory stimulation on premature infants, and variability exists in reported outcomes.

PURPOSE

To explore the effects of olfactory and gustatory stimulation on feeding outcomes in preterm infants.

DATA SOURCES

A literature search was conducted in 4 databases (CENTRAL, PubMed, Embase, CINAHL) from the inception of the databases to May 2024.

STUDY SELECTION

Randomized controlled trials (RCTs) or quasi-RCTs to explore the effects of olfactory and gustatory stimulation on feeding outcomes in preterm infants were included.

DATA EXTRACTION

Two reviewers independently extracted data from the included studies and completed the form designed for data extraction.

RESULTS

Eleven RCTs and quasi-RCTs comprising 1009 preterm infants were included. Meta-analysis found that olfactory and gustatory stimulation significantly shortened the time to reach full oral feeds ( days ) (mean difference [MD]: -2.52, 95% confidence interval [CI]: -3.88 to -1.16, P = .0003), while they had no significant differences in time to achieve full enteral feeds ( days ), postmenstrual age (PMA) at the removal of the nasogastric tube ( weeks ), weight at discharge ( grams ), weight gain ( grams ), head circumference at discharge ( cm ), length at discharge ( cm ), total duration of parenteral nutrition ( days ), necrotizing enterocolitis, hospitalization duration ( days ), PMA at discharge ( weeks ).

IMPLICATIONS FOR PRACTICE AND RESEARCH

Large sample, multicenter studies are needed to demonstrate the effectiveness of olfactory and gustatory stimulation on feeding outcomes in preterm infants.

Optimizing Neonatal Prefeeding Habilitation: A Holistic Approach Integrating Neonatal Learning Behaviors, Motor Development, and Evidence-Based Interventions

Neonatal clinicians utilize prefeeding interventions with premature infants to promote a natural process of oral-sensory development, hoping to prepare the infant for future oral feeding. Prefeeding interventions require a holistic approach, ensuring infants are actively involved in learning. Therapists can achieve this by prioritizing the development of intentionality, which is the conscious pursuit of action driven by motivation. The authors present a conceptual model of six neonatal behavioral states of learning called the "Neonatal Intentional Capacities." This model illustrates how purposeful actions evolve into extended learning sequences and helps determine how well an infant can participate in learning experiences. The authors will elucidate the dynamic relationship between intentionality and the development of adaptive motor skills of prefeeding. Lastly, this article presents a consolidated and categorized grouping of current evidence-based prefeeding interventions. Utilizing the framework presented, the authors offer clinical guidance to support prefeeding treatment planning.

Exposure to the smell and taste of milk to accelerate feeding in preterm infants

BACKGROUND

Preterm infants (born before 37 weeks' gestation) are often unable to co-ordinate sucking, swallowing, and breathing for oral feeding because of their immaturity. In such cases, initial nutrition is provided by orogastric or nasogastric tube feeding. Feeding intolerance is common and can delay attainment of full enteral and sucking feeds, prolonging the need for nutritional support and the hospital stay. Smell and taste play an important role in the activation of physiological pre-absorptive processes that contribute to food digestion and absorption. However, during tube feeding, milk bypasses the nasal and oral cavities, limiting exposure to the smell and taste of milk. Provision of the smell and taste of milk with tube feeds offers a non-invasive and low-cost intervention that, if effective in accelerating the transition to enteral feeds and subsequently to sucking feeds, would bring considerable advantages to infants, their families, and healthcare systems.

OBJECTIVES

To assess whether exposure to the smell or taste (or both) of breastmilk or formula administered with tube feeds can accelerate the transition to full sucking feeds without adverse effects in preterm infants.

SEARCH METHODS

We conducted searches in CENTRAL, MEDLINE, Embase, CINAHL, and Epistemonikos to 26 April 2023. We also searched clinical trial databases and conference proceedings.

SELECTION CRITERIA

We included randomised and quasi-randomised studies that evaluated exposure versus no exposure to the smell or taste of milk (or both) immediately before or at the time of tube feeds.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed risk of bias, and extracted data according to Cochrane Neonatal methodology. We performed meta-analyses using risk ratios (RRs) for dichotomous data and mean differences (MDs) for continuous data, with their respective 95% confidence intervals (CIs). We used GRADE to assess the certainty of evidence.

MAIN RESULTS

We included eight studies (1277 preterm infants). Seven studies (1244 infants) contributed data for meta-analysis. The evidence suggests that exposure to the smell and taste of milk with tube feeds has little to no effect on time taken to reach full sucking feeds (MD -1.07 days, 95% CI -2.63 to 0.50; 3 studies, 662 infants; very low-certainty evidence). Two studies reported no adverse effects related to the intervention. The intervention may have little to no effect on duration of parenteral nutrition (MD 0.23 days, 95% CI -0.24 to 0.71; 3 studies, 977 infants; low-certainty evidence), time to reach full enteral feeds (MD -0.16 days, 95% CI -0.45 to 0.12; 1 study, 736 infants; very low-certainty evidence) or risk of necrotising enterocolitis (RR 0.93, 95% CI 0.47 to 1.84; 2 studies, 435 infants; low-certainty evidence), although the evidence for time to reach full enteral feeds is very uncertain. Exposure to the smell and taste of milk with tube feeds probably has little to no effect on risk of late infection (RR 1.14, 95% CI 0.74 to 1.75; 2 studies, 436 infants; moderate-certainty evidence). There were no data available to assess feeding intolerance. The included studies had small sample sizes and methodological limitations, including unclear or lack of randomisation (four studies), lack of blinding of participants and personnel (five studies), unclear or lack of blinding of the outcome assessor (all eight studies), and different inclusion criteria and methods of administering the interventions.

AUTHORS' CONCLUSIONS

The results of our meta-analyses suggest that exposure to the smell and taste of milk with tube feeds may have little to no effect on time to reach full sucking feeds and time to reach full enteral feeds. We found no clear difference between exposure and no exposure to the smell or taste of milk on safety outcomes (adverse effects, necrotising enterocolitis, and late infection). Results from one ongoing study and two studies awaiting classification may alter the conclusions of this review. Future research should examine the effect of exposing preterm infants to the smell and taste of milk with tube feeds on health outcomes during hospitalisation, such as attainment of feeding skills, safety, feed tolerance, infection, and growth. Future studies should be powered to detect the effect of the intervention in infants of different gestational ages and on each sex separately. It is also important to determine the optimal method, frequency, and duration of exposure.

Effects of olfactory and/or gustatory stimuli on feeding of preterm infants: A systematic review and meta-analysis

AIM

To evaluate the effect of olfactory and/or gustatory stimulation interventions on feeding outcomes in preterm infants.

METHODS

We conducted systematic searches across various academic databases, including PubMed, Embase, Web of Science, the Cochrane Library, the Chinese Biomedical Literature Service System, China National Knowledge Infrastructure, the Wanfang Database, and the Wipu Database. These searches aimed to identify randomized controlled trials investigating the impact of olfactory and/or gustatory stimulation on preterm infants. The search period spanned from the inception of the databases until December 2022. Two independent evaluators autonomously reviewed the literature, extracted pertinent data, assessed the quality of the included studies, and conducted a meta-analysis using RevMan 5.3 software.

RESULTS

A total of 7 randomized controlled trials or quasi-experimental studies were included, with a total of 871 participants. Olfactory and gustatory stimulation demonstrated a reduction in the time to full enteral feeds in preterm infants when compared to usual care (MD = -1.60 days; 95% CI = -2.31, -0.89; p<0.0001). No substantial evidence was identified regarding the influence of olfactory and gustatory stimulation on the duration of gastric tube placement, length of hospitalization, incidence of necrotizing enterocolitis, or occurrence of spontaneous bowel perforation in preterm infants.

CONCLUSIONS

Olfactory and gustatory stimulation show potential benefits for preterm infants. However, due to the low to very low level of certainty associated with the available data, our ability to assess the effects is limited. Further trials and studies are essential to enhance our understanding of the mechanisms and effectiveness of olfactory and gustatory stimulation therapies.

Nutritional Support for Moderate-to-Late-Preterm Infants - A Randomized Trial

BACKGROUND

Most moderate-to-late-preterm infants need nutritional support until they are feeding exclusively on their mother's breast milk. Evidence to guide nutrition strategies for these infants is lacking.

METHODS

We conducted a multicenter, factorial, randomized trial involving infants born at 32 weeks 0 days' to 35 weeks 6 days' gestation who had intravenous access and whose mothers intended to breast-feed. Each infant was assigned to three interventions or their comparators: intravenous amino acid solution (parenteral nutrition) or dextrose solution until full feeding with milk was established; milk supplement given when maternal milk was insufficient or mother's breast milk exclusively with no supplementation; and taste and smell exposure before gastric-tube feeding or no taste and smell exposure. The primary outcome for the parenteral nutrition and the milk supplement interventions was the body-fat percentage at 4 months of corrected gestational age, and the primary outcome for the taste and smell intervention was the time to full enteral feeding (150 ml per kilogram of body weight per day or exclusive breast-feeding).

RESULTS

A total of 532 infants (291 boys [55%]) were included in the trial. The mean (±SD) body-fat percentage at 4 months was similar among the infants who received parenteral nutrition and those who received dextrose solution (26.0±5.4% vs. 26.2±5.2%; adjusted mean difference, -0.20; 95% confidence interval [CI], -1.32 to 0.92; P = 0.72) and among the infants who received milk supplement and those who received mother's breast milk exclusively (26.3±5.3% vs. 25.8±5.4%; adjusted mean difference, 0.65; 95% CI, -0.45 to 1.74; P = 0.25). The time to full enteral feeding was similar among the infants who were exposed to taste and smell and those who were not (5.8±1.5 vs. 5.7±1.9 days; P = 0.59). Secondary outcomes were similar across interventions. Serious adverse events occurred in one infant.

CONCLUSIONS

This trial of routine nutrition interventions to support moderate-to-late-preterm infants until full nutrition with mother's breast milk was possible did not show any effects on the time to full enteral feeding or on body composition at 4 months of corrected gestational age. (Funded by the Health Research Council of New Zealand and others; DIAMOND Australian New Zealand Clinical Trials Registry number, ACTRN12616001199404.).

Effects of human milk odor stimulation on feeding in premature infants: a systematic review and meta-analysis

Previous studies suggested odor stimulation may influence feeding of premature neonates. Therefore, this systematic review and meta-analysis of randomized controlled trials was conducted to assess the effect of human milk odor stimulation on feeding of premature infants. All randomized controlled trials related to human milk odor stimulation on feeding in premature infants published in PubMed, Cochrane, Library, Medline, Embase, Web of science databases and Chinese biomedical literature databases, China National Knowledge Infrastructure, China Science and Technology Journal Database (VIP) and Wanfang Chinese databases were searched, and The Cochrane Handbook 5.1.0 was used to evaluate the quality and authenticity of the literature. Relevant information of the included studies was extracted and summarized, and the evaluation indexes were analyzed using ReviewManager5.3. The retrieval time was from the establishment of the database to July 28, 2022.12 articles were assessed for eligibility, and six randomized controlled studies were eventually included in the meta-analysis (PRISMA). A total of 6 randomized controlled studies with 763 patients were finally included in the study, and the quality evaluation of literatures were all grade B. Human milk odor stimulation reduced the transition time to oral feeding in premature infants [SMD = - 0.48, 95% CI (- 0.69, - 0.27), Z = 4.54, P < 0.00001] and shortened the duration of parenteral nutrition [MD = - 1.01, 95% CI (- 1.70, - 0.32), Z = 2.88, P = 0.004]. However, it did not change the length of hospitalization for premature infants [MD = - 0.03, 95% CI (- 0.41, 0.35), Z = 0.17, P = 0.86]. The implementation of human milk odor stimulation can reduce the transition time to oral feeding and the duration of parenteral nutrition in premature infants, but further studies are needed to determine whether it can reduce the length of hospital stay in premature infants. More high-quality, large-sample studies are needed to investigate the effect of human milk odor stimulation on the feeding process and other outcomes in premature infants.

Vanilla odor promotes oral feeding in premature infants-A randomized controlled trial

PROPOSE

Introducing early oral feeding in premature infants is important because it supports intestinal maturation and helps prevent infections. In addition, early oral feeding is likely to contribute to improved neurocognitive outcomes in preterm infants. Several holistic therapeutic strategies have been developed to improve feeding skills, food tolerance, and the ability to drink independently, including practices such as early breastfeeding, oral stimulation, and subsequent olfactory stimulation. Based on several studies using olfactory stimulation with food odors (vanilla, breast milk) to promote oral feeding in preterm infants this study was conducted to test the following hypothesis: Does olfactory stimulation with vanilla or milk odor (breast milk or formula) lead to a reduction in the time required for nasogastric tube weaning in premature infants older than 26 + 6 weeks of gestational age? In addition, does it influence secondary outcomes such as length of hospital stay, weight development, and attainment of greater amounts of independently consumed food?

METHODS

Premature with complete or partial feeding by gastric tube and without ventilation were included. For this study, 207 infants over 26 + 6 gestational weeks were randomized into three different study groups. Before each feeding, an olfactory presentation was made with milk odor, a vanilla Sniffin' Stick, or a control stick. In the final analysis, 165 infants were included (87 males, 78 females). At the time of randomization, infants were on average 12 ± 9.5 days old.

RESULTS

While the influence of vanilla and milk odor did not provide a significant difference from the control for the primary outcome, a secondary analysis showed a significant group difference in the cumulative amount of independently drunk food consumed in the first ten days was the highest amount in the vanilla group. This time period was chosen due to the high dropout rate after the first ten days. In addition, there was a promising significance for earlier hospital discharge for prematurely below 32 weeks of gestation receiving vanilla odor stimulation in comparison to milk odor stimulation.

CONCLUSION

Although the primary outcome of this study (gastric tube removal) did not provide significant results, a significant benefit of vanilla olfactory stimulation for preterm infants was demonstrated in subgroup analysis above milk odor stimulation. Younger preterm infants seem to benefit from the stimulation.

Oral stimulation for promoting oral feeding in preterm infants

BACKGROUND

Preterm infants (< 37 weeks' post-menstrual age (PMA)) are often delayed in attaining oral feeding. Normal oral feeding is suggested as an important outcome for the timing of discharge from the hospital and can be an early indicator of neuromotor integrity and developmental outcomes. A range of oral stimulation interventions may help infants to develop sucking and oromotor co-ordination, promoting earlier oral feeding and earlier hospital discharge. This is an update of our 2016 review.

OBJECTIVES

To determine the effectiveness of oral stimulation interventions for attainment of oral feeding in preterm infants born before 37 weeks' PMA.

SEARCH METHODS

Searches were run in March 2022 of the following databases: CENTRAL via CRS Web; MEDLINE and Embase via Ovid. We also searched clinical trials databases and the reference lists of retrieved articles for randomised controlled trials (RCTs) and quasi-randomised trials. Searches were limited by date 2016 (the date of the search for the original review) forward. Note: Due to circumstances beyond our control (COVID and staffing shortages at the editorial base of Cochrane Neonatal), publication of this review, planned for mid 2021, was delayed. Thus, although searches were conducted in 2022 and results screened, potentially relevant studies found after September 2020 have been placed in the section, Awaiting Classification, and not incorporated into our analysis.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials comparing a defined oral stimulation intervention with no intervention, standard care, sham treatment or non-oral intervention (e.g. body stroking protocols or gavage adjustment protocols) in preterm infants and reporting at least one of the specified outcomes.

DATA COLLECTION AND ANALYSIS

Following the updated search, two review authors screened the titles and abstracts of studies and full-text copies when needed to identify trials for inclusion in the review. The primary outcomes of interest were time (days) to exclusive oral feeding, time (days) spent in NICU, total hospital stay (days), and duration (days) of parenteral nutrition. All review and support authors contributed to independent extraction of data and analysed assigned studies for risk of bias across the five domains of bias using the Cochrane Risk of Bias assessment tool. The GRADE system was used to rate the certainty of the evidence. Studies were divided into two groups for comparison: intervention versus standard care and intervention versus other non-oral or sham intervention. We performed meta-analysis using a fixed-effect model.

MAIN RESULTS

We included 28 RCTs (1831 participants). Most trials had methodological weaknesses, particularly in relation to allocation concealment and masking of study personnel. Oral stimulation compared with standard care Following meta-analysis, it is uncertain whether oral stimulation reduces the time to transition to oral feeding compared with standard care (mean difference (MD) -4.07 days, 95% confidence interval (CI) -4.81 to -3.32 days, 6 studies, 292 infants; I2 =85%, very low-certainty evidence due to serious risk of bias and inconsistency). Time (days) spent in the neonatal intensive care unit (NICU) was not reported. It is uncertain whether oral stimulation reduces the duration of hospitalisation (MD -4.33, 95% CI -5.97 to -2.68 days, 5 studies, 249 infants; i2 =68%, very low-certainty evidence due to serious risk of bias and inconsistency). Duration (days) of parenteral nutrition was not reported. Oral stimulation compared with non-oral intervention Following meta-analysis, it is uncertain whether oral stimulation reduces the time to transition to exclusive oral feeding compared with a non-oral intervention (MD -7.17, 95% CI -8.04 to -6.29 days, 10 studies, 574 infants; I2 =80%, very low-certainty evidence due to serious risk of bias, inconsistency and precision). Time (days) spent in the NICU was not reported. Oral stimulation may reduce the duration of hospitalisation (MD -6.15, 95% CI -8.63 to -3.66 days, 10 studies, 591 infants; I2 =0%, low-certainty evidence due to serious risk of bias). Oral stimulation may have little or no effect on the duration (days) of parenteral nutrition exposure (MD -2.85, 95% CI -6.13 to 0.42, 3 studies, 268 infants; very low-certainty evidence due to serious risk of bias, inconsistency and imprecision).

AUTHORS' CONCLUSIONS

There remains uncertainty about the effects of oral stimulation (versus either standard care or a non-oral intervention) on transition times to oral feeding, duration of intensive care stay, hospital stay, or exposure to parenteral nutrition for preterm infants. Although we identified 28 eligible trials in this review, only 18 provided data for meta-analyses. Methodological weaknesses, particularly in relation to allocation concealment and masking of study personnel and caregivers, inconsistency between trials in effect size estimates (heterogeneity), and imprecision of pooled estimates were the main reasons for assessing the evidence as low or very low certainty. More well-designed trials of oral stimulation interventions for preterm infants are warranted. Such trials should attempt to mask caregivers to treatment when possible, paying particular attention to blinding of outcome assessors. There are currently 32 ongoing trials. Outcome measures that reflect improvements in oral motor skill development as well as longer term outcome measures beyond six months of age need to be defined and used by researchers to capture the full impact of these interventions.

Smell and taste of milk during tube feeding of preterm infants: neurodevelopmental follow-up of the randomized TASTE trial, study protocol

BACKGROUND

The Taste And Smell To Enhance nutrition (TASTE) trial investigated the effects of smell and taste of milk with tube feeding compared to routine care on the growth of preterm infants. There was no difference between groups in growth (weight, head circumference, length) z-scores at discharge from the hospital. Infants in the intervention group had higher head circumference and length z-scores at 36 weeks postmenstrual age, both secondary outcomes. The objective of this follow-up study is to assess 2-year neurodevelopmental and growth outcomes after exposure of preterm infants to the smell and taste of milk with tube feeding compared to routine care.

METHODS

This is a neurodevelopmental follow-up study of a two-center, placebo-controlled randomized trial. Infants born before 29 weeks postmenstrual age and/or with a birth weight of less than 1250 g were randomized to smell and taste of milk with each tube feed or routine care. The current follow-up assessed the 2-year neurodevelopmental and growth outcomes of participants of the TASTE trial discharged from the hospital (n = 334). The primary outcome is survival free of any major neurodevelopmental impairment comprising any moderate/severe cerebral palsy (Gross Motor Function Classification System score II-V), Bayley Scales of Infant and Toddler Development, Third/Fourth Edition (Bayley-III/Bayley-4) motor, cognitive, or language scores < -2SD, blindness, or deafness at 2 years of age. Other outcomes include death, breastfeeding within the first year, and respiratory support, oral feeding, and anthropometric parameters at 2 years of age. The Human Research Ethics Committees of Mater Misericordiae Limited and the Royal Women's Hospital approved the TASTE trial including the neurodevelopmental follow-up described in this protocol.

DISCUSSION

For patients and their families, the neurodevelopmental outcomes of preterm infants are of utmost importance. Consequently, they should be investigated following any interventional study performed during the newborn period. Furthermore, improved weight gain and head growth in the hospital are associated with better long-term neurodevelopmental outcomes. Smelling and tasting of milk is an uncomplicated and cost-effective intervention that may improve the growth and neurodevelopmental outcomes of preterm infants. Potential limitations affecting this follow-up study, caused by the COVID-19 pandemic, are anticipated and discussed in this protocol.

TRIAL REGISTRATION

Name of the registry: Australian and New Zealand Clinical Trials Registry; Registration number: ACTRN12617000583347 ; Registration date: 26 April 2017.

State of the Science on the Benefits of Human Milk for Hospitalized, Vulnerable Neonates

Research on human milk has increased dramatically in recent years. The purpose of this review is to describe the literature on the health benefits of human milk for hospitalized, vulnerable neonates. PubMed, CINAHL, and Embase were searched for research articles reporting the health outcomes of hospitalized neonates who were exposed to human milk. Human milk, particularly a mother's own milk, has the potential to reduce the risk of death and the risk and severity of necrotizing enterocolitis, infection, retinopathy of prematurity, bronchopulmonary dysplasia, intraventricular hemorrhage, kidney disease, and liver disease. Dose and timing of human milk is important, with more human milk and earlier introduction having a greater impact on health. When a mother's own milk is not available, donor human milk provides benefits over infant formula.

Experience-dependent plasticity of gustatory insular cortex circuits and taste preferences

Early experience with food influences taste preference in adulthood. How gustatory experience influences development of taste preferences and refinement of cortical circuits has not been investigated. Here, we exposed weanling mice to an array of taste solutions and determined the effects on the preference for sweet in adulthood. We demonstrate an experience-dependent shift in sucrose preference persisting several weeks following the termination of exposure. A shift in sucrose palatability, altered neural responsiveness to sucrose, and inhibitory synaptic plasticity in the gustatory portion of the insular cortex (GC) were also induced. The modulation of sweet preference occurred within a restricted developmental window, but restoration of the capacity for inhibitory plasticity in adult GC reactivated the sensitivity of sucrose preference to taste experience. Our results establish a fundamental link between gustatory experience, sweet preference, inhibitory plasticity, and cortical circuit function and highlight the importance of early life nutrition in setting taste preferences.