Short-term dietary compensation in free-living adults

Calorie Compensation Patterns Observed in App-Based Food Diaries

Self-regulation of food intake is necessary for maintaining a healthy body weight. One of the characteristics of self-regulation is calorie compensation. Calorie compensation refers to adjusting the current meal's energy content based on the energy content of the previous meal(s). Preload test studies measure a single instance of compensation in a controlled setting. The measurement of calorie compensation in free-living conditions has largely remained unexplored. This paper proposes a methodology that leverages extensive app-based observational food diary data to measure an individual's calorie compensation profile in free-living conditions. Instead of a single compensation index followed in preload-test studies, we present the compensation profile as a distribution of days a user exhibits under-compensation, overcompensation, non-compensation, and precise compensation. We applied our methodology to the public food diary data of 1622 MyFitnessPal users. We empirically established that four weeks of food diaries were sufficient to characterize a user's compensation profile accurately. We observed that meal compensation was more likely than day compensation. Dinner compensation had a higher likelihood than lunch compensation. Precise compensation was the least likely. Users were more likely to overcompensate for missing calories than for additional calories. The consequences of poor compensatory behavior were reflected in their adherence to their daily calorie goal. Our methodology could be applied to food diaries to discover behavioral phenotypes of poor compensatory behavior toward forming an early behavioral marker for weight gain.

Ultraprocessed Foods and Obesity Risk: A Critical Review of Reported Mechanisms

Epidemiologic evidence supports a positive association between ultraprocessed food (UPF) consumption and body mass index. This has led to recommendations to avoid UPFs despite very limited evidence establishing causality. Many mechanisms have been proposed, and this review critically aimed to evaluate selected possibilities for specificity, clarity, and consistency related to food choice (i.e., low cost, shelf-life, food packaging, hyperpalatability, and stimulation of hunger/suppression of fullness); food composition (i.e., macronutrients, food texture, added sugar, fat and salt, energy density, low-calorie sweeteners, and additives); and digestive processes (i.e., oral processing/eating rate, gastric emptying time, gastrointestinal transit time, and microbiome). For some purported mechanisms (e.g., fiber content, texture, gastric emptying, and intestinal transit time), data directly contrasting the effects of UPF and non-UPF intake on the indices of appetite, food intake, and adiposity are available and do not support a unique contribution of UPFs. In other instances, data are not available (e.g., microbiome and food additives) or are insufficient (e.g., packaging, food cost, shelf-life, macronutrient intake, and appetite stimulation) to judge the benefits versus the risks of UPF avoidance. There are yet other evoked mechanisms in which the preponderance of evidence indicates ingredients in UPFs actually moderate body weight (e.g., low-calorie sweetener use for weight management; beverage consumption as it dilutes energy density; and higher fat content because it reduces glycemic responses). Because avoidance of UPFs holds potential adverse effects (e.g., reduced diet quality, increased risk of food poisoning, and food wastage), it is imprudent to make recommendations regarding their role in diets before causality and plausible mechanisms have been verified.

A Culturally Sensitive and Theory-Based Intervention on Prevention and Management of Diabetes: A Cluster Randomized Control Trial

Type 2 diabetes is an emerging concern in Kenya. This clustered-randomized trial of peri-urban communities included a theory-based and culturally sensitive intervention to improve diabetes knowledge, health beliefs, dietary intake, physical activity, and weight status among Kenyan adults. Those in the intervention group (IG) received a culturally sensitive diabetes education intervention which applied the Health Belief Model in changing knowledge, health beliefs and behavior. Participants attended daily education sessions for 5 days, each lasting 3 h and received mobile phone messages for an additional 4 weeks. The control group (CG) received standard education on COVID-19. Data was collected at baseline, post-intervention (1 week), and follow-up assessment (5 weeks). Linear mixed effect analysis was performed to assess within and across group differences. Compared to the control, IG significantly increased diabetes knowledge (p < 0.001), health beliefs including perceived susceptibility (p = 0.05), perceived benefits (p = 0.04) and self-efficacy (p = 0.02). IG decreased consumption of oils (p = 0.03), refined grains (p = 0.01), and increased intake of fruits (p = 0.01). Perceived barriers, physical activity, and weight status were not significantly different between both groups. The findings demonstrate the potential of diabetes education in improving diabetes knowledge, health beliefs, and in changing dietary intake of among adults in Kenya.

'Joining the Dots': Individual, Sociocultural and Environmental Links between Alcohol Consumption, Dietary Intake and Body Weight-A Narrative Review

Alcohol is energy-dense, elicits weak satiety responses relative to solid food, inhibits dietary fat oxidation, and may stimulate food intake. It has, therefore, been proposed as a contributor to weight gain and obesity. The aim of this narrative review was to consolidate and critically appraise the evidence on the relationship of alcohol consumption with dietary intake and body weight, within mainstream (non-treatment) populations. Publications were identified from a PubMed keyword search using the terms 'alcohol', 'food', 'eating', 'weight', 'body mass index', 'obesity', 'food reward', 'inhibition', 'attentional bias', 'appetite', 'culture', 'social'. A snowball method and citation searches were used to identify additional relevant publications. Reference lists of relevant publications were also consulted. While limited by statistical heterogeneity, pooled results of experimental studies showed a relatively robust association between acute alcohol intake and greater food and total energy intake. This appears to occur via metabolic and psychological mechanisms that have not yet been fully elucidated. Evidence on the relationship between alcohol intake and weight is equivocal. Most evidence was derived from cross-sectional survey data which does not allow for a cause-effect relationship to be established. Observational research evidence was limited by heterogeneity and methodological issues, reducing the certainty of the evidence. We found very little qualitative work regarding the social, cultural, and environmental links between concurrent alcohol intake and eating behaviours. That the evidence of alcohol intake and body weight remains uncertain despite no shortage of research over the years, indicates that more innovative research methodologies and nuanced analyses are needed to capture what is clearly a complex and dynamic relationship. Also, given synergies between 'Big Food' and 'Big Alcohol' industries, effective policy solutions are likely to overlap and a unified approach to policy change may be more effective than isolated efforts. However, joint action may not occur until stronger evidence on the relationship between alcohol intake, food intake and weight is established.

High Intake of Free Sugars, Fructose, and Sucrose Is Associated with Weight Gain in Japanese Men

BACKGROUND

Available evidence for associations between sugar intake and body weight is largely from short-term controlled trials and studies focusing on sugar-sweetened beverages. Studies on long-term weight change related to the intake of types of sugar are thus needed.

OBJECTIVE

We examined the associations between weight change and the intake of various types of carbohydrates, including starch, total sugars, and free or naturally occurring sugars and saccharides (i.e., glucose, fructose, sucrose, and lactose), among Japanese men and women.

METHODS

This prospective cohort study included 14,971 residents of Takayama City in Japan who were aged 35-69 y at the first survey in 1992 and responded to a self-administrated questionnaire at the second survey in 2002. We excluded those with cancer, coronary artery disease, stroke, or diabetes on the first survey and those with missing information about body weight on both surveys, leaving 13,229 participants for analysis (5879 men and 7350 women). Mean (95% CI) values of 10-y weight change according to types of carbohydrates were estimated using linear regression models with adjustment for total energy intake and other dietary and lifestyle factors. Dietary intake was assessed at the first survey using a validated FFQ.

RESULTS

Among men, free sugar intake was associated with weight gain and the estimated means (95% CIs) of weight change were -0.60 (-0.67, -0.54), -0.31 (-0.38, -0.24), -0.12 (-0.19, -0.05), and 0.20 (0.13, 0.27) kg from the first to fourth quartiles (P-trend = 0.002). Moreover, high intakes of sucrose and fructose were associated with weight gain (P-trend: 0.018 for sucrose and 0.001 for fructose). Among women, the intake of any type of carbohydrate was not significantly associated with weight change.

CONCLUSIONS

These results suggested that high intakes of free sugars, sucrose, and fructose were associated with long-term weight gain among Japanese men.

Portion size normality and additional within-meal food intake: two crossover laboratory experiments

Reducing food portion size could reduce energy intake. However, it is unclear at what point consumers respond to reductions by increasing intake of other foods. We predicted that a change in served portion size would only result in significant additional eating within the same meal if the resulting portion size was no longer visually perceived as 'normal'. Participants in two crossover experiments (Study 1: n 45; Study 2: n 37; adults, 51 % female) were served different-sized lunchtime portions on three occasions that were perceived by a previous sample of participants as 'large-normal', 'small-normal' and 'smaller than normal', respectively. Participants were able to serve themselves additional helpings of the same food (Study 1) or dessert items (Study 2). In Study 1 there was a small but significant increase in additional intake when participants were served the 'smaller than normal' compared with the 'small-normal' portion (m difference = 161 kJ, P = 0·002, d = 0·35), but there was no significant difference between the 'small-normal' and 'large-normal' conditions (m difference = 88 kJ, P = 0·08, d = 0·24). A similar pattern was observed in Study 2 (m difference = 149 kJ, P = 0·06, d = 0·18; m difference = 83 kJ, P = 0·26, d = 0·10). However, smaller portion sizes were each associated with a significant reduction in total meal intake. The findings provide preliminary evidence that reductions that result in portions appearing 'normal' in size may limit additional eating, but confirmatory research is needed.

Meal-Concurrent Media Use is Associated with Increased Dietary Intake with no Evidence of Next Meal Compensation in Free-Living Adults

OBJECTIVE

This study aimed to determine the effects of concurrent and prior media use on dietary intake and dietary compensation over 3 days in a free-living population.

METHODS

Participants recorded food intake and media use for a 3-day period. The US Department of Agriculture multiple-pass method was used to ensure completeness of food records. Energy, protein, fiber, carbohydrates, sugar, added sugar, fat, saturated fat, trans fat, and sodium intake were assessed.

RESULTS

Meals consumed while participants used media included 149.3 more calories on average than meals consumed without media. Media meals were higher in protein, carbohydrates, fat, and saturated fat. There was no evidence of dietary compensation at the meal following the media meal.

CONCLUSIONS

Energy and macronutrient intake increased during media-paired meals. Dietary compensation at the subsequent meal did not occur, suggesting that the effects of media-paired meals are additive over the short term.

Modelling the Association between Core and Discretionary Energy Intake in Adults with and without Obesity

BACKGROUND

Many dietary recommendations for weight control rely on the assumption that greater core food intake will displace intake of energy-dense discretionary foods and beverages. However, there is little evidence to support these assumptions. This study examined the naturalistic relationship between daily core and discretionary energy intake, and with discretionary food and discretionary beverage intake, separately. The impact of weight status on these associations was also examined.

METHOD

One hundred participants completed a four-day (non-consecutive) estimated food diary. Discretionary foods and beverages were identified by reference to the Australian Dietary Guidelines. Non-discretionary items were considered core items. Simultaneous-equation random effects models using disaggregated dietary data controlling for sociodemographic variables were used to determine the association between various dietary components.

RESULT

Core energy intake correlated negatively with discretionary energy intake (cross-equation correlation, ρ = -0.49 (95% CI: -0.57, -0.39)). Its correlation with discretionary foods (-0.47 (-0.56, -0.37)) was stronger than that with discretionary beverages (-0.19 (-0.30, -0.07)) The correlation between core energy intake and discretionary energy intake was significantly stronger in participants who did not have obesity (-0.67 (-0.71, -0.50)) than those with obesity (-0.32 (-0.46, -0.17)) (p = 0.0002).

CONCLUSIONS

Core and discretionary energy intake share an inverse and potentially bidirectional, relationship that appears to be stronger with discretionary foods than discretionary beverages. These relationships were significantly weaker in participants with obesity which may indicate less precise dietary compensation in these individuals. While strategies that promote greater intake of core foods may assist with weight maintenance in individuals of healthy weight, its impact in individuals with obesity may be limited. These strategies should be accompanied by direct messages to reduce commensurately the intake of discretionary items, with special attention paid to discretionary beverage consumption.

Macronutrient manipulations of cheese resulted in lower energy content without compromising its satiating capacity

Manipulation of food's macronutrient composition in order to reduce energy content without compromising satiating capacity may be helpful in body weight control. For cheeses, substituting fat with protein may provide such opportunity. We aimed at examining the acute effect of cheeses with different macronutrient compositions on accumulated energy intake and subjective appetite sensation. A total of thirty-nine normal-weight (average BMI 24·4 kg/m²) men and women completed the partly double-blind, randomised crossover study with high-protein/low-fat (HP/LF, 696 kJ), high-protein/high-fat (HP/HF, 976 kJ) and low-protein/high-fat (LP/HF, 771 kJ) cheeses. After overnight fasting, 80 g cheese were served with 70 g bread, 132 g juice and 125 g coffee/tea/water. Ad libitum spaghetti bolognaise was served after 3 h and energy intake assessed. Subjective appetite ratings were assessed using visual analogue scales. Composite appetite scores were calculated and evaluated relatively to energy intake. Total accumulated energy intake was 188·3 (se 97·4) kJ lower when consuming the HP/LF compared with the HP/HF (P ≤ 0·05), but, compared with the LP/HF cheese, the difference was not significant (177·0 (se 100·4) kJ lower; P = 0·08). In relation to energy intake, the composite appetite score was lower when consuming the HP/LF compared with the HP/HF (P = 0·003) and the LP/HF (P = 0·007) cheeses. Thereby, no compensatory eating following consumption of the HP/LF compared with the HP/HF cheese was found. The HP/LF cheese resulted in an increased feeling of satiety in relation to its lower energy content compared with both HP/HF and LP/HF cheeses.

Effect of resistant wheat starch on subjective appetite and food intake in healthy adults

OBJECTIVE

The aim of this study was to determine the effect of replacing standard wheat flour (SWF) with resistant wheat starch (RWS) on markers of appetite and food intake in healthy adults.

METHODS

A randomized, single-blind, crossover study was conducted with 27 healthy adults (ages 23 ± 2 y with a body mass index of 23.0 ± 3.0 kg/m²). After an overnight fast, muffins that contained only SWF or muffins in which 40% of the SWF was replaced with RWS were consumed as part of the breakfast meal. Appetite questionnaires and plasma samples were collected before the test meal and at 10 time points after meal consumption. An ad libitum meal was provided 240 min after breakfast, and the amount eaten was recorded. Food intake was recorded over the remainder of the day using a diet diary, and appetite was measured hourly using appetite questionnaires. Plasma was assayed to measure biomarkers of satiety and glycemia.

RESULTS

Replacing SWF with RWS had no effect on subjective appetite or energy intake at the lunch meal (P > 0.05). Total daily energy intake (including the breakfast meal) was reduced by 179 kcal when participants consumed the RWS muffins (P = 0.05). Replacing SWF with RWS reduced plasma insulin (P < 0.05) but had no effect on plasma glucose, cholecystokinin, glucagon-like peptide-1, or peptide YY_3-36 concentration (P > 0.05).

CONCLUSIONS

These results indicate that replacing SWF with RWS decreases plasma insulin concentration and reduces energy intake over a 24-h period.

Sweetening of the global diet, particularly beverages: patterns, trends, and policy responses

Evidence suggests that excessive intake of added sugars has adverse effects on cardiometabolic health, which is consistent with many reviews and consensus reports from WHO and other unbiased sources. 74% of products in the US food supply contain caloric or low-calorie sweeteners, or both. Of all packaged foods and beverages purchased by a nationally representative sample of US households in 2013, 68% (by proportion of calories) contain caloric sweeteners and 2% contain low-calorie sweeteners. We believe that in the absence of intervention, the rest of the world will move towards this pervasiveness of added sugars in the food supply. Our analysis of trends in sales of sugar-sweetened beverages around the world, in terms of calories sold per person per day and volume sold per person per day, shows that the four regions with the highest consumption are North America, Latin America, Australasia, and western Europe. The fastest absolute growth in sales of sugar-sweetened beverages by country in 2009-14 was seen in Chile. We believe that action is needed to tackle the high levels and continuing growth in sales of such beverages worldwide. Many governments have initiated actions to reduce consumption of sugar-sweetened beverages in the past few years, including taxation (eg, in Mexico); reduction of their availability in schools; restrictions on marketing of sugary foods to children; public awareness campaigns; and positive and negative front-of-pack labelling. In our opinion, evidence of the effectiveness of these actions shows that they are moving in the right direction, but governments should view them as a learning process and improve their design over time. A key challenge for policy makers and researchers is the absence of a consensus on the relation of beverages containing low-calorie sweeteners and fruit juices with cardiometabolic outcomes, since decisions about whether these are healthy substitutes for sugar-sweetened beverages are an integral part of policy design.

Portion size and obesity

Portion size is a key environmental driver of energy intake, and larger-than-appropriate portion sizes could increase the risk of weight gain. Multiple acute, well-controlled laboratory studies, supported by data from free-living settings, demonstrated that portion size has a powerful and proportionate effect on the amount of food consumed. Of particular importance is that bouts of overeating associated with large portions are sustained and not followed by a compensatory reduction in energy intake. The positive effect of portion size on energy intake was demonstrated for different types of foods and beverages, and is particularly pronounced with energy-dense foods. The predisposition to overeat in response to large portions is pervasive and occurs regardless of demographic characteristics, such as socioeconomic status, age, body mass index, and sex. Secular trends toward greater availability of large portions, coupled with value-size pricing, effectively distorted consumption norms and perceptions of what is an appropriate amount to eat. Nevertheless, although a direct causal link between portion size and obesity remains to be established, advice to moderate portion sizes, especially of energy-dense foods, is presently the cornerstone of most weight management advice. Although many strategies have been proposed to counteract the deleterious effects of portion size, there are few data indicating which are likely to be acceptable in the medium- to long term. Further research is urgently needed to establish what types of interventions targeted at portion size are likely to be effective, in what settings, and among which target groups.

The Bright Side of Stress-Induced Eating

Previous research suggests that approximately 40% to 50% of the population increase food consumption under stressful conditions. The prevailing view is that eating in response to stress is a type of maladaptive self-regulation. Past research has concentrated mainly on the negative effects of social stress on eating. We propose that positive social experiences may also modulate eating behavior. In the present study, participants were assigned to social-exclusion, neutral, and social-inclusion conditions. In a subsequent bogus taste test, the amount of ice cream eaten and habitual stress-related eating were measured. After being socially excluded, people who habitually eat more in response to stress (stress hyperphagics) ate significantly more than people who habitually eat less in response to stress (stress hypophagics). Conversely, after being socially included, stress hyperphagics ate significantly less than stress hypophagics. The present findings provide the first evidence for complementary adjustments of food consumption across positive and negative situations. Implications of these findings for the relationship of stress and body weight are discussed.

Will reducing sugar-sweetened beverage consumption reduce obesity? Evidence supporting conjecture is strong, but evidence when testing effect is weak

We provide arguments to the debate question and update a previous meta-analysis with recently published studies on effects of sugar-sweetened beverages (SSBs) on body weight/composition indices (BWIs). We abstracted data from randomized controlled trials examining effects of consumption of SSBs on BWIs. Six new studies met these criteria: (i) human trials, (ii) ≥ 3 weeks duration, (iii) random assignment to conditions differing only in consumption of SSBs and (iv) including a BWI outcome. Updated meta-analysis of a total of seven studies that added SSBs to persons' diets showed dose-dependent increases in weight. Updated meta-analysis of eight studies attempting to reduce SSB consumption showed an equivocal effect on BWIs in all randomized subjects. When limited to subjects overweight at baseline, meta-analysis showed a significant effect of roughly 0.25 standard deviations (more weight loss/less weight gain) relative to controls. Evidence to date is equivocal in showing that decreasing SSB consumption will reduce the prevalence of obesity. Although new evidence suggests that an effect may yet be demonstrable in some populations, the integrated effect size estimate remains very small and of equivocal statistical significance. Problems in this research area and suggestions for future research are highlighted.

Psychometric properties and construct validity of the Weight-Related Eating Questionnaire in a diverse population

This study evaluates the 16-item, four-factor Weight-Related Eating Questionnaire (WREQ), which assesses theory-based aspects of eating behavior, across diverse, nonclinical subgroups. A total of 621 men and women aged 18-81 years (34.3 ± 16.4) with a mean BMI of 25.7 ± 6.1 kg/m(2) (range 15.5-74.1 kg/m(2)) were recruited from general education classes at the University of Hawai'i, Manoa and an online survey panel of Hawai'i residents to complete a web-based survey. Participants were predominantly white (23%), Asian/Asian-mix (42%), or Native Hawaiian/Pacific Islander (18%). The WREQ's factor structure was successfully replicated by confirmatory factor analysis (CFA) for the entire sample and by weight status, gender, age, and race with strong internal consistency. Four-week test-retest reliability (n = 31) for the subscales was excellent with interclass correlations of 0.849-0.932. Tests of population invariance confirmed the generalizability of the WREQ across all subgroups having provided no evidence that the factor structure, factor loadings, or indicator intercepts varied significantly between the groups. Multivariate regression analyses showed that emotional eating was independently associated with BMI (β = 0.272, P < 0.001) as well as moderate- and long-term weight change rates (weight gain) in young adults (β = 0.152, P = 0.042) and adults (β = 0.217, P = 0.001). Compensatory restraint was negatively associated with weight gain in adults (β = -0.133, P = 0.039). Routine restraint and emotional eating were highest among dieters. All associations remained significant after accounting for gender, age, and race. The hypothesized WREQ measurement model demonstrated very good construct validity, confirming the unbiased generalizability of the WREQ measure across sex, age, race, and BMI subgroups, and excellent criterion-related validity with respect to current BMI, weight change, and weight control status.

Reproducibility of 24-h post-exercise changes in energy intake in overweight and obese women using current methodology

Direct observation(s) of energy intake (EI) via buffet meals served in the laboratory are often carried out within short-term exercise intervention studies. The reproducibility of values obtained has not been assessed either under resting control conditions or post-exercise, in overweight and obese females. A total of fourteen sedentary, pre-menopausal females (BMI 30·0 (sd5·1) kg/m2) completed four trials; two exercise and two control. Each trial lasted 24 h spanning over 2 d; conducted from afternoon on day 1 and morning on day 2. An exercise session to expend 1·65 MJ was completed on day 1 of exercise trials, and three buffet meals were served during each trial. Reproducibility of post-exercise changes in energy and macronutrient intakes was assessed at each individual buffet meal by intraclass correlation coefficient (ri). Only therivalues for post-exercise changes in energy (ri0·44 (95 % CI − 0·03, 0·77),P = 0·03) and fat intake (ri0·51 (95 % CI 0·04, 0·81),P = 0·02) at the lunch buffet meal achieved statistical significance; however, theserivalues were weak and had large associated 95 % CI, which indicates a large degree of variability associated with these measurements. Energy and macronutrient intakes at the breakfast and evening buffet meals were not reproducible. This study concludes that the frequently used laboratory-based buffet meal method of assessing EI does not produce reliable, reproducible post-exercise changes in EI in overweight and obese women.

Effects of growth hormone and nutritional therapy in boys with constitutional growth delay: a randomized controlled trial

OBJECTIVE

To examine whether supplemental nutrition augments the anabolic actions of growth hormone (GH) in boys with constitutional delay of growth and maturation (CDGM).

STUDY DESIGN

We conducted a randomized, controlled trial at an outpatient clinical research center. Subjects were 20 prepubertal boys (age, 9.3 ± 1.3 years) with CDGM (height standard deviation score, -2.0 ± 0.5; bone age delay, 1.8 ± 0.8 years; body mass index standard deviation score, -1.2 ± 1.0; peak stimulated GH, 15.7 ± 7.7 ng/mL), who were randomized (n = 10/group) to 6 months observation or daily nutritional supplementation, followed by additional daily GH therapy in all for another 12 months. t tests and repeated measures analyses of variance compared energy intake, total energy expenditure (TEE), growth, hormones, and nutrition markers.

RESULTS

Energy intake was increased at 6 months within the nutrition group (P = .04), but not the observation group, and TEE was not statistically different within either group at 6 months. Addition of 6 months GH resulted in higher energy intake and TEE in the GH/nutrition group at 12 months (P < .01), but not in the GH group versus baseline. Height, weight, lean body mass, hormones, and nutrition markers increased comparably in both groups throughout 18 months.

CONCLUSION

Boys with CDGM use energy at an accelerated rate, an imbalance not overcome with added nutrition. GH therapy increases growth comparably with or without added nutrition in these patients.

Nonnutritive sweetener consumption in humans: effects on appetite and food intake and their putative mechanisms

Nonnutritive sweeteners (NNS) are ecologically novel chemosensory signaling compounds that influence ingestive processes and behavior. Only about 15% of the US population aged >2 y ingest NNS, but the incidence is increasing. These sweeteners have the potential to moderate sugar and energy intakes while maintaining diet palatability, but their use has increased in concert with BMI in the population. This association may be coincidental or causal, and either mode of directionality is plausible. A critical review of the literature suggests that the addition of NNS to non-energy-yielding products may heighten appetite, but this is not observed under the more common condition in which NNS is ingested in conjunction with other energy sources. Substitution of NNS for a nutritive sweetener generally elicits incomplete energy compensation, but evidence of long-term efficacy for weight management is not available. The addition of NNS to diets poses no benefit for weight loss or reduced weight gain without energy restriction. There are long-standing and recent concerns that inclusion of NNS in the diet promotes energy intake and contributes to obesity. Most of the purported mechanisms by which this occurs are not supported by the available evidence, although some warrant further consideration. Resolution of this important issue will require long-term randomized controlled trials.

Relationships between human thirst, hunger, drinking, and feeding

There is a widely held view that hunger prompts feeding to ensure energy needs are met, while thirst cues drinking to address hydration requirements. However, recent changes in the nature of the food supply and eating patterns have raised questions about the functionality of these relationships with respect to maintaining energy balance. The increasing consumption of energy-yielding beverages and foods with diluted energy density, through the use of ingredients such as high-intensity sweeteners and fat replacers, poses new challenges to presumed homeostatic energy regulatory mechanisms. This review draws on findings from a recent observational study and other published evidence to explore whether shifts of food composition and use patterns may be disrupting relationships between thirst, hunger, drinking, and eating, resulting in positive energy balance (e.g., drinking low satiety, energy-yielding beverages in response to hunger). The observational study entailed collecting hourly appetitive ratings and dietary recalls from 50 adults for seven consecutive days. These data reveal a clear bimodal daily hunger pattern, whereas thirst is stronger and more stable throughout the day. Further, approximately 75% of fluid intake occurs peri-prandially, with the majority derived from energy-yielding beverages. While there is published evidence that drinking is responsive to feeding, support for the view that drinking is the more tightly regulated behavior is stronger. Our data indicates that, due to a number of plausible factors, neither absolute values nor changes of hunger or thirst are strong predictors of energy intake. However, it is proposed that stable, high thirst facilitates drinking, and with the increased availability and use of energy-yielding beverages that have low satiety properties, can promote positive energy balance. There are marked individual differences in mean daily hunger and thirst ratings with unknown implications for energy balance.