The effects of the spontaneous ingestion of particular foods or beverages on the meal pattern and overall nutrient intake of humans

Introduction to the dietary management of obesity in adults

Obesity is a multifaceted and complex condition that requires holistic management. It currently affects nearly one in four adults in the UK, with the UK ranked 10th globally for the highest obesity rates. Obesity is projected to have an economic burden of ∼£2 billion per year by 2030 in the UK.1 Excess weight gain can coincide with myriad health concerns and multiple health conditions, which can be physical, metabolic or psychosocial. This includes type 2 diabetes mellitus (T2DM), hypertension, coronary heart disease, osteoarthritis, obstructive sleep apnoea, reproductive disorders, depression and cancer2; hence, there has been a significant emphasis on obesity prevention. Obesity is often associated with weight stigma, impacting psychological wellbeing and quality of life. This can influence an individual's likelihood of seeking support, delaying appropriate input from healthcare professionals, with a knock-on effect on pre-existing health conditions. This review explores the management of obesity from a nutritional perspective, because modifying dietary intake is essential to reduce the risk of non-communicable diseases, including those associated with obesity.

Longitudinal Associations of Dietary Sugars and Glycaemic Index with Indices of Glucose Metabolism and Body Fatness during 3-Year Weight Loss Maintenance: A PREVIEW Sub-Study

BACKGROUND

Dietary sugars are often linked to the development of overweight and type 2 diabetes (T2D) but inconsistencies remain.

OBJECTIVE

We investigated associations of added, free, and total sugars, and glycaemic index (GI) with indices of glucose metabolism (IGM) and indices of body fatness (IBF) during a 3-year weight loss maintenance intervention.

DESIGN

The PREVIEW (PREVention of diabetes through lifestyle Intervention and population studies in Europe and around the World) study was a randomised controlled trial designed to test the effects of four diet and physical activity interventions, after an 8-week weight-loss period, on the incidence of T2D. This secondary observational analysis included pooled data assessed at baseline (8), 26, 52, 104 and 156 weeks from 514 participants with overweight/obesity (age 25-70 year; BMI ≥ 25 kg⋅m^-2) and with/without prediabetes in centres that provided data on added sugars (Sydney and Helsinki) or free sugars (Nottingham). Linear mixed models with repeated measures were applied for IBF (total body fat, BMI, waist circumference) and for IGM (fasting insulin, HbA1c, fasting glucose, C-peptide). Model A was adjusted for age and intervention centre and Model B additionally adjusted for energy, protein, fibre, and saturated fat.

RESULTS

Total sugars were inversely associated with fasting insulin and C-peptide in all centres, and free sugars were inversely associated with fasting glucose and HbA1c (Model B: all p < 0.05). Positive associations were observed between GI and IGM (Model B: fasting insulin, HbA1c, and C-peptide: (all p < 0.01), but not for added sugars. Added sugar was positively associated with body fat percentage and BMI, and GI was associated with waist circumference (Model B: all p < 0.01), while free sugars showed no associations (Model B: p > 0.05).

CONCLUSIONS

Our findings suggest that added sugars and GI were independently associated with 3-y weight regain, but only GI was associated with 3-y changes in glucose metabolism in individuals at high risk of T2D.

The effects of the form of sugar (solid vs. beverage) on body weight and fMRI activation: A randomized controlled pilot study

Objective

To test if sugar sweetened beverages (SSBs) and sugar sweetened solids (SSSs) have differential effects on body weight and reward processing in the brain.

Methods

In a single blind randomized controlled pilot trial (RCT), twenty participants with BMI between 20 and 40 kg/m² were randomized to consume a 20 fluid ounce soda (SSB, 248 kcal) or the equivalent in solid form (SSS; similar to thick gelatin or gummy candy) daily. At baseline and day 28, fasting body weight and fed-state BOLD fMRI of the brain were assessed. Differences in fMRI signals between views of low-fat (LF (<30%)) high sugar (HS (>30%)) food, and non-food images were calculated in brain regions implicated in energy homeostasis, taste, and reward.

Results

All participants in the SSB (6F 4M; 8 Caucasian; 36±14 y, 28.2±5.5 kg/m²; Mean±SD) and SSS (3F 7M; 6 Caucasian; 39±12; 26.3±4.4) groups completed the study. Weight change was 0.27±0.78 kg between SSB and SSS participants. Changes in the fMRI response to LF/HS foods in reward, homeostatic and taste regions tended to not be different between the groups over the four weeks. However, activation of the right substantia nigra increased following the SSB but decreased activation following the SSS in response to LF/HS foods over 28 days (-0.32±0.12). Ratings of wanting for LF/HS foods were correlated with activation in several brain regions, including the OFC.

Conclusions

Change in weight was modest between the groups in this study. Daily consumption of a SSB over 28 days led to mixed responses to LF/HS foods in areas of the brain associated with reward. Ratings of wanting are correlated with fMRI activation inside an MRI scanner.

A narrative review of the effects of sugar-sweetened beverages on human health: A key global health issue

The provision of healthy and safe food is vital for human health, and the addition of unnecessary sugars in foodstuffs is an important global issue, leading to multiple long- and short-term health issues and spiraling costs for individuals and governments alike. The negative effect of excess sugar consumption contributes to adverse health conditions, including obesity, type 2 diabetes, and poor oral health in both high and low resource settings. A key plank of governmental and health promotion bodies' nutritional guidance is to raise public awareness of "hidden" sugars, salt, and fats, such as found in processed foods and sugar-sweetened beverages (SSBs), and guide individuals to reduce their consumption. This rapid narrative review brings together some of the key issues identified in the literature around the consumption of SSBs, including patterns of consumption, the general impact on human health and nutrition, specific effects on oral health and the oral microbiome, and strategies to address over-consumption. The range of long-term adverse effects on health is often misunderstood or unknown by the public. However, some strategies have succeeded in reducing the consumption of SSBs, including public health strategies and interventions and the imposition of taxes or levies, and this article makes recommendations for action.

Trends in Beverage Consumption Among Children and Adults, 2003-2014

OBJECTIVE

This study aimed to provide the most recent national estimates for beverage consumption among children and adults in the United States.

METHODS

Dietary data were collected from 18,600 children aged 2 to 19 years and from 27,652 adults aged ≥ 20 years in the 2003 to 2014 National Health and Nutrition Examination Survey. Total beverage and sugar-sweetened beverage (SSB) consumption was measured by 24-hour dietary recall.

RESULTS

From 2003 to 2014, per capita consumption of all beverages declined significantly among children (473.8-312.6 calories; P < 0.001) and adults (425.0-341.1 calories; P < 0.001). In the 2013-2014 survey, 60.7% of children and 50.0% of adults drank SSBs on a given day, which is significantly lower than 2003-2004, when 79.7% of children and 61.5% of adults reported drinking SSBs. From 2003 to 2014, per capita consumption of SSBs declined from 224.6 calories to 132.5 calories (P < 0.001) for children and from 190.4 calories to 137.6 calories (P < 0.001) for adults. The absolute levels for the percentage of SSB drinkers and per capita consumption of SSBs were highest among black, Mexican American, and non-Mexican Hispanic children, adolescents, and young adults for all years of the study.

CONCLUSIONS

Overall, beverage and SSB consumption declined for children and adults from 2003 to 2014. The levels of consumption are highest among black, Mexican American, and non-Mexican Hispanic participants.

Changes in Sugar-Sweetened Soda Consumption, Weight, and Waist Circumference: 2-Year Cohort of Mexican Women

OBJECTIVES

To evaluate 2-year changes in soda consumption, weight, and waist circumference.

METHODS

We followed 11 218 women from the Mexican Teachers' Cohort from 2006 to 2008. Dietary data were collected using a semiquantitative food frequency questionnaire. Weight was self-reported, and waist circumference was self-measured. We used linear regression to evaluate changes in sugar-sweetened and sugar-free soda consumption in relation to changes in weight and waist circumference, adjusting for lifestyle and other dietary factors.

RESULTS

Compared with no change, a decrease in sugar-sweetened soda consumption by more than 1 serving per week was associated with less weight gain (-0.4 kg; 95% confidence interval [CI] = -0.6, -0.2). Conversely, relative to no change, an increase in sugar-sweetened soda by more than 1 serving per week was associated with a 0.3-kilogram (95% CI = 0.2, 0.5) increase in weight. An increase of 1 serving per day of sugar-sweetened soda was associated with a 1.0 kg (95% CI = 0.7, 1.2; P < .001) increase in weight. The results for waist circumference were similar.

CONCLUSIONS

Moderate changes in consumption of sugar-sweetened soda over a 2-year period were associated with corresponding changes in weight and waist circumference among Mexican women.

Sugar and artificially sweetened beverages linked to obesity: a systematic review and meta-analysis

BACKGROUND/OBJECTIVES

Artificial sweeteners are used widely to replace caloric sugar as one of the strategies to lessen caloric intake. However, the association between the risk of obesity and artificially sweetened soda consumption is controversial. The objective of this meta-analysis aimed to assess the association between consumption of sugar and artificially sweetened soda and obesity.

METHODS

A literature search was performed using MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, and Cochrane Central Register of Controlled Trials from inception through May 2015. Studies that reported relative risks, odd ratios, or hazard ratios comparing the risk of obesity in patients consuming either sugar or artificially sweetened soda vs. those who did not consume soda were included. Pooled risk ratios (RRs) and 95% CI were calculated using a random-effect, generic inverse variance method.

RESULTS

Eleven studies were included in our analysis to assess the association between consumption of sugar-sweetened soda and obesity. The pooled RR of obesity in patients consuming sugar-sweetened soda was 1.18 (95% CI, 1.10-1.27). Three studies were included to assess the association between consumption of artificially sweetened soda and obesity. The pooled RR of obesity in patients consuming artificially sweetened soda was 1.59 (95% CI, 1.22-2.08).

CONCLUSIONS

Our study demonstrated a significant association between sugar and artificially sweetened soda consumption and obesity. This finding raises awareness and question of negative clinical impact on both sugar and artificially sweetened soda and the risk of obesity.

Relation of total sugars, fructose and sucrose with incident type 2 diabetes: a systematic review and meta-analysis of prospective cohort studies

BACKGROUND

Sugar-sweetened beverages are associated with type 2 diabetes. To assess whether this association holds for the fructose-containing sugars they contain, we conducted a systematic review and meta-analysis of prospective cohort studies.

METHODS

We searched MEDLINE, Embase, CINAHL and the Cochrane Library (through June 2016). We included prospective cohort studies that assessed the relation of fructose-containing sugars with incident type 2 diabetes. Two independent reviewers extracted relevant data and assessed risk of bias. We pooled risk ratios (RRs) using random effects meta-analyses. The overall quality of the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system.

RESULTS

Fiffeen prospective cohort studies (251 261 unique participants, 16 416 cases) met the eligibility criteria, comparing the highest intake (median 137, 35.2 and 78 g/d) with the lowest intake (median 65, 9.7 and 25.8 g/d) of total sugars, fructose and sucrose, respectively. Although there was no association of total sugars (RR 0.91, 95% confidence interval [CI] 0.76-1.09) or fructose (RR 1.04, 95% CI 0.84-1.29) with type 2 diabetes, sucrose was associated with a decreased risk of type 2 diabetes (RR 0.89, 95% CI 0.80-0.98). Our confidence in the estimates was limited by evidence of serious inconsistency between studies for total sugars and fructose, and serious imprecision in the pooled estimates for all 3 sugar categories.

INTERPRETATION

Current evidence does not allow us to conclude that fructose-containing sugars independent of food form are associated with increased risk of type 2 diabetes. Further research is likely to affect our estimates.

TRIAL REGISTRATION

ClinicalTrials.gov, no. NCT01608620.

Sugar-Sweetened Beverage Consumption by Adult Caregivers and Their Children

Objective. To examine how parents’ beliefs about beverage attributes and exposure to sugar-sweetened beverage (SSB) advertising are associated with parents’ and their children’s SSB consumption. Design. Cross-sectional representative telephone survey of Philadelphia parents in households with children between the ages of 3 and 16 years. Participants. Three hundred and seventy-one randomly selected survey respondents. The response rate was 27% using the American Association for Public Opinion Research RR3 formula. Main Outcome Measures. SSB consumption, health ratings of SSBs, exposure to SSB ads, and exposure to anti-SSB public service advertisements. Analysis. Seemingly unrelated regression was used to correct for Type I error and significance levels were set at .05 or less. Results. Assessment of SSB “healthiness” was associated with the increased adult consumption of SSBs for three of the five SSBs and associated with children’s consumption for all four SSBs with child consumption data. For both groups, ratings of SSB sugar and caloric content were not related to consumption. Adult exposure to SSB-specific advertising was related to consumption for three of five SSBs and two of four SSBs consumed by children. Conclusions and Implications. These results suggest that sugar and calories are not relevant to consumption, absent an explicit connection to a healthiness evaluation of SSBs.

The effect of non-caloric sweeteners on cognition, choice, and post-consumption satisfaction

Consumers often turn to non-caloric sweeteners (NCS) as a means of promoting a healthy body weight. However, several studies have now linked their long-term use to increased weight gain, raising the question of whether these products produce unintended psychological, physiological, or behavioral changes that have implications for weight management goals. In the following, we present the results of three experiments bearing on this issue, testing whether NCS-consumption influences how individuals think about and respond to food. Participants in each of our three experiments were randomly assigned to consume a sugar-sweetened beverage, an unsweetened beverage, or a beverage sweetened with NCS. We then measured their cognition (Experiment 1), product choice (Experiment 2), and subjective responses to a sugar-sweetened food (Experiment 3). Results revealed that consuming NCS-sweetened beverages influences psychological processes in ways that - over time - may increase calorie intake.

Sucrose compared with artificial sweeteners: a clinical intervention study of effects on energy intake, appetite, and energy expenditure after 10 wk of supplementation in overweight subjects

BACKGROUND

There is a lack of appetite studies in free-living subjects supplying the habitual diet with either sucrose or artificially sweetened beverages and foods. Furthermore, the focus of artificial sweeteners has only been on the energy intake (EI) side of the energy-balance equation. The data are from a subgroup from a 10-wk study, which was previously published.

OBJECTIVE

The objective was to investigate changes in EI and energy expenditure (EE) as possible reasons for the changes in body weight during 10 wk of supplementation of either sucrose or artificial sweeteners in overweight subjects.

DESIGN

Supplements of sucrose-sweetened beverages and foods (2 g/kg body weight; n = 12) or similar amounts containing artificial sweeteners (n = 10) were given single-blind in a 10-wk parallel design. Beverages accounted for 80% and solid foods for 20% by weight of the supplements. The rest of the diet was free choice. Indirect 24-h whole-body calorimetry was performed at weeks 0 and 10. At week 0 the diet was a weight-maintaining standardized diet. At week 10 the diet consisted of the supplements and ad libitum choice of foods. Visual analog scales were used to record appetite.

RESULTS

Body weight increased in the sucrose group and decreased in the sweetener group during the intervention. The sucrose group had a 3.3-MJ higher EI but felt less full and had higher ratings of prospective food consumption than did the sweetener group at week 10. Basal metabolic rate was increased in the sucrose group, whereas 24-h EE was increased in both groups at week 10. Energy balance in the sucrose group was more positive than in the sweetener group at the stay at week 10.

CONCLUSION

The changes in body weight in the 2 groups during the 10-wk intervention seem to be attributable to changes in EI rather than to changes in EE.

Diet-beverage consumption and caloric intake among US adults, overall and by body weight

OBJECTIVES

We examined national patterns in adult diet-beverage consumption and caloric intake by body-weight status.

METHODS

We analyzed 24-hour dietary recall with National Health and Nutrition Examination Survey 1999-2010 data (adults aged ≥ 20 years; n = 23 965).

RESULTS

Overall, 11% of healthy-weight, 19% of overweight, and 22% of obese adults drink diet beverages. Total caloric intake was higher among adults consuming sugar-sweetened beverages (SSBs) compared with diet beverages (2351 kcal/day vs 2203 kcal/day; P = .005). However, the difference was only significant for healthy-weight adults (2302 kcal/day vs 2095 kcal/day; P < .001). Among overweight and obese adults, calories from solid-food consumption were higher among adults consuming diet beverages compared with SSBs (overweight: 1965 kcal/day vs 1874 kcal/day; P = .03; obese: 2058 kcal/day vs 1897 kcal/day; P < .001). The net increase in daily solid-food consumption associated with diet-beverage consumption was 88 kilocalories for overweight and 194 kilocalories for obese adults.

CONCLUSIONS

Overweight and obese adults drink more diet beverages than healthy-weight adults and consume significantly more solid-food calories and a comparable total calories than overweight and obese adults who drink SSBs. Heavier US adults who drink diet beverages will need to reduce solid-food calorie consumption to lose weight.

Effects of fruit and vegetable, consumed in solid vs beverage forms, on acute and chronic appetitive responses in lean and obese adults

BACKGROUND

The effects of fruits and vegetables in solid vs beverage forms on human appetite and food intake, acutely and chronically, are unclear.

METHODS

This 21-week, randomized, crossover study assessed appetitive ratings following the inclusion of fruits and vegetables, in solid and beverage form, into the habitual diet of healthy lean (n=15) and overweight/obese (n=19) adults with low customary consumption. The primary acute outcomes were satiation (amount of challenge meal consumed), satiety (latency of subsequent eating event) and dietary compensation after a 400 kcal fruit preload. Ratings of appetite were also obtained before and after 8 weeks of required increased fruit and vegetable consumption (20% estimated energy requirement).

RESULTS

Acutely, overweight/obese participants reported smaller reductions of hunger after consuming the fruit preload in beverage compared with solid form (preload × form × body mass index effects, P=0.03). Participants also consumed significantly less of a challenge meal (in both gram and energy) after the ingestion of the solid fruit preload (P<0.005). However, the subsequent meal latency was not significantly different between the solid and the beverage fruit preloads. Total daily energy intake was significantly higher when the obese participants consumed the beverage fruit preload compared with the solid (P<0.001). Daily energy intake was markedly, but not significantly, higher among the lean with the beverage vs solid food form. Hunger and fullness ratings remained stable when participants consumed fruits and vegetables in solid or beverage form for 8 weeks each.

CONCLUSION

Acute post-ingestive appetitive responses were weaker following consumption of fruits in beverage vs solid food forms. Consumption of beverage or solid fruit and vegetable food loads for 8 weeks did not chronically alter appetitive responses.

Plants, diet, and health

Chronic disease is a major social challenge of the twenty-first century. In this review, we examine the evidence for discordance between modern diets and those on which humankind evolved as the cause of the increasing incidence of chronic diseases, and the evidence supporting consumption of plant foods as a way to reduce the risk of chronic disease. We also examine the evidence for avoiding certain components of plant-based foods that are enriched in Western diets, and review the mechanisms by which different phytonutrients are thought to reduce the risk of chronic disease. This body of evidence strongly suggests that consuming more fruits and vegetables could contribute both to medical nutrition therapies, as part of a package of treatments for conditions like type 2 diabetes, heart disease, cancer, and obesity, and to the prevention of these diseases. Plant science should be directed toward improving the quality of plant-based foods by building on our improved understanding of the complex relationships between plants, our diet, and our health.

Overweight and obese humans overeat away from home

The built environment has been implicated in the development of the epidemic of obesity. We investigated the differences in the meal patterns of normal weight vs. overweight/obese individuals occurring at home vs. other locations. The location of meals and their size in free-living participants were continuously recorded for 7 consecutive days. Study 1: 81 males and 84 females recorded their intake in 7-day diet diaries and wore a belt that contained a GPS Logger to record their location continuously for 7 consecutive days. Study 2: 388 males and 621 females recorded their intake in diet diaries for 7 consecutive days. In both studies, compared to eating at home, overweight/obese participants ate larger meals away from home in both restaurants and other locations than normal weight participants. Overweight/obese individuals appear to be more responsive to environmental cues for eating away from home. This suggests that the influence of the built environment on the intake of overweight/obese individuals may contribute to the obesity epidemic.

Fruit drink consumption is associated with overweight and obesity in Canadian women

OBJECTIVE

Overweight and obesity in Canada have significantly increased during the last three decades, paralleled by increased intake of fat and sugar, particularly sugary beverages. The Canadian Community Health Survey, Cycle 2.2, conducted in 2004 (CCHS 2.2), provides the opportunity to evaluate beverage intakes in relation to overweight and obesity using body mass index (BMI). Our objective was to examine the association between sugar-sweetened beverages and BMI in Canadian adults.

METHODS

CCHS 2.2 data were used (n=14,304, aged >18 years and < or =65 years) and dietary intake was assessed on the basis of single 24-hour recall. Using cluster analysis (K-means method), males and females were classified into distinct clusters based on the dominant pattern of beverage intakes. Logistic regression models were used to determine associations between dominant beverage consumption patterns and BMI, controlling for age and other confounding factors.

RESULTS

BMI in women with predominant "fruit drink" pattern (28.3 +/- 1.0 kg/m2) was higher than in those with no dominant pattern (26.8 +/- 0.3 kg/m2), p < 0.001. Adjusting for energy intake and other potential confounders, high intake of fruit drinks was a significant predictor of overweight (OR=1.84, 95% CI: 1.06-3.20), obesity (OR = 2.55, 95% CI: 1.46-4.47) and overweight/obesity (OR = 2.05, 95% CI: 1.29-3.25) in women. In men, mean BMI was not different among beverage consumption clusters and none of the beverage intake patterns was a predictor for overweight and obesity.

CONCLUSION

Using a nationally representative dataset, there was an association between sugar-sweetened beverages and overweight and obesity in Canadian women.

Mode of consumption plays a role in alleviating hunger and thirst

While studying the effect of structure on satiety, effects of mode of consumption, additional water to drink, and thirst have been neglected. The objective was to assess effects of structure, mode of consumption of food, and additional drinking of water on fullness and thirst. In study 1, 20 subjects (BMI 22.5 ± 0.5 kg/m(2); age 21.4 ± 3 years) underwent consumption conditions; SEW: solids to eat + 750 ml water to drink; LEW: liquefied soup to eat including 500 ml water + 250 ml water separately to drink; LDW: the same as LEW but served as drinks; SE, LE, and LD: the same as previous but without water to drink. In study 2, a subset of subjects underwent consumption conditions: solid carbohydrate, solid protein, solid fat: the same as SEW, but for each macronutrient separately; liquefied carbohydrate, liquefied protein, liquefied fat: the same as LEW, but for each macronutrient separately. Appetite, insulin concentration, glucose concentration, and ghrelin concentration were measured. Eating, independent of structure, suppressed desire to eat more than drinking (P < 0.01). Drinking water separately vs. water consumption in the food suppressed thirst more (P < 0.001). Regarding protein, satiety was higher in the solid vs. liquefied condition, while blood parameters were not significantly different. Only after drinking a meal most subjects (80%) wanted to consume more of the same meal, in order to alleviate hunger (63%) or quench thirst (37%). We conclude that mode of consumption plays a role in alleviating hunger and thirst. Subjects required further consumption after drinking the meal, motivated by hunger or thirst, showing that drinking a meal causes confusion that may imply a risk of overconsumption.

Beverage consumption, appetite, and energy intake: what did you expect?

BACKGROUND

Beverage consumption is implicated in the overweight/obesity epidemic through the weaker energy compensation response it elicits compared with solid food forms. However, plausible mechanisms are not documented.

OBJECTIVE

This study assessed the cognitive and sensory contributions of differential postingestive responses to energy- and macronutrient-matched liquid (in beverage form) and solid food forms and identifies physiologic processes that may account for them.

DESIGN

Fifty-two healthy adults [mean ± SD age: 24.7 ± 5.5 y; BMI (in kg/m(2)): 26.3 ± 6.3] completed this randomized, 4-arm crossover study. Participants consumed oral liquid and solid preloads that they perceived, through cognitive manipulation, to be liquid or solid in their stomach (ie, oral liquid/perceived gastric liquid, oral liquid/perceived gastric solid, oral solid/perceived gastric liquid, or oral solid/perceived gastric solid). However, all preloads were designed to present a liquid gastric challenge. Appetite, gastric-emptying and orocecal transit times, and selected endocrine responses were monitored for the following 4 h; total energy intake was also recorded.

RESULTS

Oral-liquid and perceived gastric-liquid preloads elicited greater postprandial hunger and lower fullness sensations, more rapid gastric-emptying and orocecal transit times, attenuated insulin and glucagon-like peptide 1 release, and lower ghrelin suppression than did responses after oral-solid and perceived gastric-solid treatments (all P < 0.05). Faster gastric-emptying times were significantly associated with greater energy intake after consumption of perceived gastric-liquid preloads (P < 0.05). Energy intake was greater on days when perceived gastric-liquid preloads were consumed than when perceived gastric solids were consumed (2311 ± 95 compared with 1897 ± 72 kcal, P = 0.007).

CONCLUSIONS

These data document sensory and cognitive effects of food form on ingestive behavior and identify physical and endocrine variables that may account for the low satiety value of beverages. They are consistent with findings that clear, energy-yielding beverages pose a particular risk for positive energy balance. This study was registered at clinicaltrials.gov as NCT01070199.

Reduction in purchases of sugar-sweetened beverages among low-income Black adolescents after exposure to caloric information

OBJECTIVES

We examined the effect of an intervention to provide caloric information about sugar-sweetened beverages (SSBs) on the number of SSB purchases.

METHODS

We used a case-crossover design with 4 corner stores located in low-income, predominately Black neighborhoods in Baltimore, Maryland. The intervention randomly posted 1 of 3 signs with the following caloric information: (1) absolute caloric count, (2) percentage of total recommended daily intake, and (3) physical activity equivalent. We collected data for 1600 beverage sales by Black adolescents, aged 12-18 years, including 400 during a baseline period and 400 for each of the 3 caloric condition interventions.

RESULTS

Providing Black adolescents with any caloric information significantly reduced the odds of SSB purchases relative to the baseline (odds ratio [OR] = 0.56; 95% confidence interval [CI] = 0.36, 0.89). When examining the 3 caloric conditions separately, the significant effect was observed when caloric information was provided as a physical activity equivalent (OR = 0.51; 95% CI = 0.31, 0.85).

CONCLUSIONS

Providing easily understandable caloric information--particularly a physical activity equivalent--may reduce calorie intake from SSBs among low-income, Black adolescents.

Hepatic oxidative stress in fructose-induced fatty liver is not caused by sulfur amino acid insufficiency

Fructose-sweetened liquid consumption is associated with fatty liver and oxidative stress. In rodent models of fructose-mediated fatty liver, protein consumption is decreased. Additionally, decreased sulfur amino acid intake is known to cause oxidative stress. Studies were designed to test whether oxidative stress in fructose-sweetened liquid-induced fatty liver is caused by decreased ad libitum solid food intake with associated inadequate sulfur amino acid intake. C57BL6 mice were grouped as: control (ad libitum water), fructose (ad libitum 30% fructose-sweetened liquid), glucose (ad libitum 30% glucose-sweetened water) and pair-fed (ad libitum water and sulfur amino acid intake same as the fructose group). Hepatic and plasma thiol-disulfide antioxidant status were analyzed after five weeks. Fructose- and glucose-fed mice developed fatty liver. The mitochondrial antioxidant protein, thioredoxin-2, displayed decreased abundance in the liver of fructose and glucose-fed mice compared to controls. Glutathione/glutathione disulfide redox potential (E(h)GSSG) and abundance of the cytoplasmic antioxidant protein, peroxiredoxin-2, were similar among groups. We conclude that both fructose and glucose-sweetened liquid consumption results in fatty liver and upregulated thioredoxin-2 expression, consistent with mitochondrial oxidative stress; however, inadequate sulfur amino acid intake was not the cause of this oxidative stress.

Exercising women with menstrual disturbances consume low energy dense foods and beverages

Women with exercise-associated menstrual cycle disturbances (EAMD) restrict energy intake. Reducing energy density (ED; kcals·g–1of food or beverage) may be a strategy employed by EAMD women to maintain lower energy intake. The purpose of this study was 3-fold: to determine whether EAMD women consume low ED diets; to identify food groups associated with low ED; and to determine concentrations of total peptide YY (PYY), a satiety factor. Twenty-five active females were divided into 2 groups, according to menstrual status: EAMD (n = 12) and ovulatory controls (OV) (n = 13). Two 3-day diet records were analyzed for ED and other parameters. Body composition, fitness, resting metabolic rate, and PYY were measured. Groups did not differ in age, age of menarche, body mass index, maximal aerobic capacity, body fat (%), or amount of exercise per week. For fat mass (12.4 ± 1.7 vs. 14.9 ± 3.5 kg; p = 0.046), energy availability (28.8 ± 11.5 vs. 42.1 ± 9.2 kcal·kg–1FFM; p = 0.006), and energy intake (29.8 ± 9.2 vs. 36.3 ± 10.6 kcals·kg–1BW; p = 0.023), EAMD was lower than OV. ED was lower in EAMD than in OV (0.77 ± 0.06 vs. 1.06 ± 0.09 kcal·g–1; p = 0.018) when all beverages were included, but not when noncaloric beverages were excluded. Vegetable (p = 0.047) and condiment (p = 0.014) consumption and fasting PYY (pg·mL–1) (p = 0.006) were higher in EAMD. EAMD ate a lower ED diet through increased vegetable, condiment, and noncaloric beverage consumption, and exhibited higher PYY concentrations. These behaviors may represent a successful strategy to restrict calories and maximize satiety.

Contemporary nutritional transition: determinants of diet and its impact on body composition

The world has experienced a marked shift in the global BMI distribution towards reduced undernutrition and increased obesity. The collision between human biology, shaped over the millennia and modern technology, globalization, government policies and food industry practices have worked to create far-reaching energy imbalance across the globe. A prime example is the clash between our drinking habits and our biology. The shift from water and breast milk as the only beverages available, to a vast array of caloric beverages was very rapid, shaped both by our tastes and aggressive marketing of the beverage industry. Our biology, shaped over millennia by daily consumption of water and seasonal availability of food, was not ready to compensate for the liquid energies. Other dietary changes were similarly significant, particularly the shift towards increased frequency of eating and larger portions. The roles of the food and beverage production, distribution and marketing sectors in not only shaping our diet but also accelerating these changes must be understood. Apart from the role of beverages, there is much less consensus about the role of various components of our diet in energy imbalance. Understanding the determinants of change in the key components of our diet through an array of research provides insights into some of the options we face in attempting to attain a great balance between energy intake and expenditures while creating an overall healthier dietary pattern. A few countries are systematically addressing the causes of poor dietary and physical activity patterns and high energy imbalance.

Sugar-sweetened beverages and risk of obesity and type 2 diabetes: epidemiologic evidence

In recent decades, temporal patterns in SSB intake have shown a close parallel between the upsurge in obesity and rising levels of SSB consumption. SSBs are beverages that contain added caloric sweeteners such as sucrose, high-fructose corn syrup or fruit-juice concentrates, all of which result in similar metabolic effects. They include the full spectrum of soft drinks, carbonated soft drinks, fruitades, fruit drinks, sports drinks, energy and vitamin water drinks, sweetened iced tea, cordial, squashes, and lemonade, which collectively are the largest contributor to added sugar intake in the US. It has long been suspected that SSBs have an etiologic role in the obesity epidemic, however only recently have large epidemiological studies been able to quantify the relationship between SSB consumption and long-term weight gain, type 2 diabetes (T2DM) and cardiovascular disease (CVD) risk. Experimental studies have provided important insight into potential underlying biological mechanisms. It is thought that SSBs contribute to weight gain in part by incomplete compensation for energy at subsequent meals following intake of liquid calories. They may also increase risk of T2DM and CVD as a contributor to a high dietary glycemic load leading to inflammation, insulin resistance and impaired beta-cell function. Additional metabolic effects from the fructose fraction of these beverages may also promote accumulation of visceral adiposity, and increased hepatic de novo lipogenesis, and hypertension due to hyperuricemia. Consumption of SSBs should therefore be replaced by healthy alternatives such as water, to reduce risk of obesity and chronic diseases.

Soft drink consumption and obesity: it is all about fructose

PURPOSE OF REVIEW

The purpose of the review is to suggest that fructose, a component of both sucrose (common sugar) and high fructose corn syrup, should be of concern to both healthcare providers and the public.

RECENT FINDINGS

Consumption of sugar-sweetened beverages has increased steadily over the past century and with this increase has come more and more reports associating their use with the risk of overweight, diabetes and cardiometabolic disease. In a meta-analysis of the relationship between soft drink consumption and cardiometabolic risk, there was a 24% overall increased risk comparing the top and bottom quantiles of consumption. Several factors might account for this increased risk, including increased carbohydrate load and increased amounts of dietary fructose. Fructose acutely increases thermogenesis, triglycerides and lipogenesis as well as blood pressure, but has a smaller effect on leptin and insulin release than comparable amounts of glucose. In controlled feeding studies, changes in body weight, fat storage and triglycerides are observed as well as an increase in inflammatory markers.

SUMMARY

The present review concludes on the basis of the data assembled here that in the amounts currently consumed, fructose is hazardous to the cardiometabolic health of many children, adolescents and adults.

Hunger and thirst: issues in measurement and prediction of eating and drinking

Associations between hunger and eating and between thirst and drinking are generally weak. This stems, in part, from limitations in the measurement of these sensations which generally rely on temporal, motivational, metabolic and/or self-reported descriptive indices. Each is critically reviewed. Also problematic is the fact that the deterministic depletion-repletion concept of ingestive behavior fails to account for influences of a multitude of contravening cognitive, social, sensory and logistical factors. Although hunger and thirst serve some parallel purposes, sharp distinctions are also present with health implications. Of particular note are the observations that thirst ratings are higher and more stable over the day compared to hunger and thirst may be more motivating to drink than hunger is to eat. Coupling these observations with evidence that beverages have limited satiety value, they pose particular challenges and opportunities. Beverages can facilitate the delivery of nutrients to those desiring or requiring them, but also to those where they are not desired or required. The benefits and risks are a function of their use rather than their inherent properties.

Influence of environmental factors on food intake and choice of beverage during meals in teenagers: a laboratory study

Environmental conditions influence meal size in adults and children. Intake of sweet drinks could contribute significantly to energy intake and potentially affect body weight, particularly in young individuals. The objectives of the present study were to measure the lunch intake of food and drinks under controlled laboratory settings in teenagers and to compare the influence of different meal conditions. Normal-weight adolescents (fourteen males and fifteen females) participated in four standardised lunches, scheduled 1 week apart. The same popular items (meat dish, dessert, water, juice, soda) were served at all meals. Ad libitum intake was measured under four conditions: subjects ate alone; in groups; alone while viewing television; alone while listening to music. Visual analogue scales were used to assess pre- and post-meal hunger and thirst and meal palatability. Energy, solid food and fluid intake was different (significantly lower) only in the ‘eating in group’ condition, in spite of identical intensity of pre-meal hunger. More soda was consumed when participants were watching television, and more water was consumed while listening to music. Across all conditions, more soda than water was consumed. Post-meal ratings of hunger, thirst and palatability did not differ between conditions. We concluded that, in teenagers, a ‘social inhibition’ effect appears rather than the ‘social facilitation’ previously reported in adults. Although teenagers do not respond to the presence of television or another ‘distractor’ such as music by eating more, they do ingest more soda when the television is on. The social significance of meals, conditioned responses and habituation to ‘distractors’ may be different between adolescents and adults.

When, how much and what foods are eaten are related to total daily food intake

Intake in the morning is associated with a reduction in the total intake for the day, while intake at night is associated with greater overall daily intake. These associations are macronutrient specific, with morning carbohydrate intake associated with reduced daily carbohydrate intake, morning fat intake associated with reduced daily fat intake and morning protein intake associated with reduced daily protein intake. Since different types of foods contain differing proportions of macronutrients, the present study investigated the associations of different types of foods ingested at various times of day with total daily and macronutrient intakes. The intakes of 388 male and 621 female free-living individuals reported in 7 d diet diaries were reanalysed. The intakes of twenty-four different types of foods and seven different drinks occurring during the morning (04.00-10.29 hours), afternoon (10.30-16.59 hours) and evening (17.00-02.00 hours) were identified and related to overall daily intakes. Dairy foods, ice cream, beef, other meats, potatoes, pastry, nuts, chips and snacks, condiments, alcohol and soda were significantly associated with higher total intake over the day, while fruit, soup, breakfast cereal, pasta, pizza, water, coffee/tea and diet soda were either not associated or were associated with lower overall intake. Dietary energy density appeared to mediate the associations between particular foods and beverages and overall energy intake. This suggests that eating low-density foods in the morning and avoiding high-density foods at night might aid in reducing overall intake and may be useful in dietary interventions for overweight and obesity.

Reduction in consumption of sugar-sweetened beverages is associated with weight loss: the PREMIER trial

BACKGROUND

Consumption of liquid calories from beverages has increased in parallel with the obesity epidemic in the US population, but their causal relation remains unclear.

OBJECTIVE

The objective of this study was to examine how changes in beverage consumption affect weight change among adults.

DESIGN

This was a prospective study of 810 adults participating in the PREMIER trial, an 18-mo randomized, controlled, behavioral intervention trial. Measurements (weight, height, and 24-h dietary recall) were made at baseline, 6 mo, and 18 mo.

RESULTS

Baseline mean intake of liquid calories was 356 kcal/d (19% of total energy intake). After potential confounders and intervention assignment were controlled for, a reduction in liquid calorie intake of 100 kcal/d was associated with a weight loss of 0.25 kg (95% CI: 0.11, 0.39; P < 0.001) at 6 mo and of 0.24 kg (95% CI: 0.06, 0.41; P = 0.008) at 18 mo. A reduction in liquid calorie intake had a stronger effect than did a reduction in solid calorie intake on weight loss. Of the individual beverages, only intake of sugar-sweetened beverages (SSBs) was significantly associated with weight change. A reduction in SSB intake of 1 serving/d was associated with a weight loss of 0.49 kg (95% CI: 0.11, 0.82; P = 0.006) at 6 mo and of 0.65 kg (95% CI: 0.22, 1.09; P = 0.003) at 18 mo.

CONCLUSIONS

These data support recommendations to limit liquid calorie intake among adults and to reduce SSB consumption as a means to accomplish weight loss or avoid excess weight gain. This trial was registered at clinicaltrials.gov as NCT00000616.

Modifiable risk factors in relation to changes in BMI and fatness: what have we learned from prospective studies of school-aged children?

Considerable interest and resources are currently being directed to primary and secondary prevention of childhood obesity among school-aged children. Intervention studies in this age group have yielded mixed results, begging the question as to whether the correct targets for intervention have been identified. To evaluate the evidence base, we reviewed prospective observational studies published in English between 1990-2007 that reported weight or fatness changes in relation to diet, physical activity, and sedentary behavior. Sugar-sweetened beverage consumption emerged as the most consistent dietary factor in association with subsequent increases in weight status or fatness. Other foods and eating patterns showed less consistent associations and when associations were present, magnitudes were generally small. This may reflect the known limitations of standard dietary methodology to assess meal patterns and dietary intake. Findings for physical activity showed more consistent inverse associations with fatness outcomes than for weight status, and as was found for dietary factors, magnitudes of association were modest. Sedentary behavior effects on weight status differ by gender in many studies, with many, but not all, showing greater positive associations among girls. The lack of consistency observed in the studies of sedentary behaviors may reflect the range of variable definitions, measurement challenges, and the changing nature of electronic media. The intrinsic interplay among eating patterns, activity and sedentary behavior adds further complexity to the interpretation of the results of these studies. More sophisticated approaches to the analysis of these complex data in future studies may maximize what is learned. Although the classic obesity risk factors seem to play a role in the development of excess weight and fatness, some more recently identified potential factors, such as sleep, warrant further investigation in prospective studies before they are ready for evaluation using more controlled study designs.

Sip size of orangeade: effects on intake and sensory-specific satiation

Sensory-specific satiation (SSS) drives food selection and contributes to meal termination. We hypothesised that smaller sips would increase SSS due to increased oro-sensory exposure, irrespective of energy content. The objective was to determine the effects of sip size and energy content on ad libitum intake of orangeade and subjective SSS for orangeade. Orangeade intake and ratings of wanting and liking were measured before and after ad libitum orangeade consumption in a 2 × 2 cross-over design (n 53). Conditions differed in energy content (no-energy v. regular-energy orangeade) and in sip size (large, 20 g/sip v. small, 5 g/sip). The mean intake of both orangeades was lower when consumed with small sips than when consumed with large sips (regular-energy, 352 v. 493 g; no-energy, 338 v. 405 g; both P < 0·001). When consumed with large sips, the mean intake of no-energy orangeade was lower than that of regular-energy orangeade (P = 0·02). When consumed with small sips, subjective SSS (based on the desire to drink) was higher for no-energy orangeade than for regular-energy orangeade (P = 0·01), while mean intake was comparable. We concluded that smaller sip size, i.e. increased oro-sensory exposure per unit of consumption, can lower intake of sweet drinks. Only with low oro-sensory exposure (large sip size) was intake higher for an energy-containing sweet drink than for a no-energy sweet drink. This suggests that intake of sweet drinks is stimulated by (metabolic) reward value and inhibited by sensory satiation. This underpins the importance of SSS for meal termination.

Increasing consumption of sugar-sweetened beverages among US adults: 1988-1994 to 1999-2004

BACKGROUND

Consumption of sugar-sweetened beverages (SSBs) has been linked to obesity and type 2 diabetes.

OBJECTIVE

We examined national trends in SSB consumption among US adults by sociodemographic characteristics, body weight status, and weight-loss intention.

DESIGN

We analyzed 24-h dietary recall data to estimate beverage consumption among adults (aged > or = 20 y) obtained from the third National Health and Nutrition Examination Survey (NHANES III, 1988-1994; n = 15,979) and NHANES 1999-2004 (n = 13,431).

RESULTS

From 1988-1994 to 1999-2004 on the survey day, the percentage of adult SSB drinkers increased from 58% to 63% (P < 0.001), per capita consumption of SSB increased by 46 kcal/d (P = 0.001), and daily SSB consumption among drinkers increased by 6 oz (P < 0.001). In both survey periods, per capita SSB consumption was highest among young adults (231-289 kcal/d) and lowest among the elderly (68-83 kcal/d). Young blacks had the highest percentage of SSB drinkers and the highest per capita consumption compared with white and Mexican American adults (P < 0.05). Overweight-obese adults with weight-loss intention (compared with those without) were significantly less likely to drink SSB, but they still consumed a considerable amount in 1999-2004 (278 kcal/d). Among young adults, 20% of SSB calories were consumed at work.

CONCLUSIONS

Over the past decade, US adult SSB consumption has increased. SSB comprises a considerable source of total daily intake and is the largest source of beverage calories. SSB consumption is highest among subgroups also at greatest risk of obesity and type 2 diabetes.

Drinking water is associated with weight loss in overweight dieting women independent of diet and activity

BACKGROUND

Data from short-term experiments suggest that drinking water may promote weight loss by lowering total energy intake and/or altering metabolism. The long-term effects of drinking water on change in body weight and composition are unknown, however.

OBJECTIVE

This study tested for associations between absolute and relative increases in drinking water and weight loss over 12 months.

METHODS AND PROCEDURES

Secondary analyses were conducted on data from the Stanford A TO Z weight loss intervention on 173 premenopausal overweight women (aged 25-50 years) who reported <1 l/day drinking water at baseline. Diet, physical activity, body weight, percent body fat (dual-energy X-ray absorptiometry), and waist circumference were assessed at baseline, 2, 6, and 12 months. At each time point, mean daily intakes of drinking water, noncaloric, unsweetened caloric (e.g., 100% fruit juice, milk) and sweetened caloric beverages, and food energy and nutrients were estimated using three unannounced 24-h diet recalls. Beverage intake was expressed in absolute (g) and relative terms (% of beverages). Mixed models were used to test for effects of absolute and relative increases in drinking water on changes in weight and body composition, controlling for baseline status, diet group, and changes in other beverage intake, the amount and composition of foods consumed and physical activity.

RESULTS

Absolute and relative increases in drinking water were associated with significant loss of body weight and fat over time, independent of covariates.

DISCUSSION

The results suggest that drinking water may promote weight loss in overweight dieting women.

Sugar-sweetened beverages and incidence of type 2 diabetes mellitus in African American women

BACKGROUND

Type 2 diabetes mellitus is an increasingly serious health problem among African American women. Consumption of sugar-sweetened drinks was associated with an increased risk of diabetes in 2 studies but not in a third; however, to our knowledge, no data are available on African Americans regarding this issue. Our objective was to examine the association between consumption of sugar-sweetened beverages, weight gain, and incidence of type 2 diabetes mellitus in African American women.

METHODS

A prospective follow-up study of 59,000 African American women has been in progress since 1995. Participants reported on food and beverage consumption in 1995 and 2001. Biennial follow-up questionnaires ascertained new diagnoses of type 2 diabetes. The present analyses included 43,960 women who gave complete dietary and weight information and were free from diabetes at baseline. We identified 2713 incident cases of type 2 diabetes mellitus during 338,884 person-years of follow-up. The main outcome measure was the incidence of type 2 diabetes mellitus.

RESULTS

The incidence of type 2 diabetes mellitus was higher with higher intake of both sugar-sweetened soft drinks and fruit drinks. After adjustment for confounding variables including other dietary factors, the incidence rate ratio for 2 or more soft drinks per day was 1.24 (95% confidence interval, 1.06-1.45). For fruit drinks, the comparable incidence rate ratio was 1.31 (95% confidence interval, 1.13-1.52). The association of diabetes with soft drink consumption was almost entirely mediated by body mass index, whereas the association with fruit drink consumption was independent of body mass index.

CONCLUSIONS

Regular consumption of sugar-sweetened soft drinks and fruit drinks is associated with an increased risk of type 2 diabetes mellitus in African American women. While there has been increasing public awareness of the adverse health effects of soft drinks, little attention has been given to fruit drinks, which are often marketed as a healthier alternative to soft drinks.

The effects of food viscosity on bite size, bite effort and food intake

Two studies investigated the effect of a food's viscosity on bite size, bite effort and food intake using a standardized protocol in which subjects sipped through a straw every 20 s for a period of 15 min from one of two products, a chocolate-flavored dairy drink and a chocolate-flavored dairy semi-solid, matched for energy density. In the first study, subjects consumed 47% more from the liquid than from the semi-solid to reach the same degree of satiation, with larger bite sizes for the liquid throughout the 15 minute period (8.7+/-0.45 g) compared to the semi-solid (5.8+/-0.3 g, p<0.01). In the second study bite effort was eliminated by using a peristaltic pump to present the products every 20 s. Oral processing time before swallowing was set at 5 s (both products) or 8 s (semi-solid). With the elimination of bite effort and a standardized oral processing time, subjects consumed as much from the semi-solid as from the liquid to reach the same degree of satiation. Bite size for liquids started relatively small and grew gradually over successive bites, whereas the bite size for the semi-solid food started relatively large and became gradually smaller. The latter effect was even more pronounced when the oral processing time was increased from 5 to 8 s. In conclusion, semi-solids resulted in smaller bite sizes and lower intake than liquids, but these differences disappeared when differences in bite effort were eliminated.

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.

Genetic and shared environmental influences on children's 24-h food and beverage intake: sex differences at age 7 y

BACKGROUND

The genetics of habitual food and beverage intake in early childhood is poorly understood.

OBJECTIVE

The objective was to test the magnitude of genetic and environmental influences on 24-h food and beverage intake in 7-y-old children. The association between intake of specific food-beverage categories and child body mass index (BMI; in kg/m(2)) was also tested.

DESIGN

A classic twin design was conducted, using the MacArthur Longitudinal Study of Twins. There were 792 children, including 396 boys from 102 monozygotic and 96 dizygotic twin pairs and 396 girls from 112 monozygotic and 86 dizygotic twin pairs; Children's 24-h dietary intake was estimated by parental recall, from which 9 composite food-beverage categories were derived. Height and weight were converted to BMI. Biometrical analyses of children's daily intake of food-beverage categories and BMI were conducted.

RESULTS

There was consistent evidence of genetic influences on children's 24-h intake of food and beverages (servings/d), especially among boys. Seven categories showed significant heritability estimates among boys, ranging from 12% (fish and lemon) to 79% (peanut butter and jelly). Only 3 categories showed significant heritability estimates among girls, ranging from 20% (bread and butter) to 56% (fish and lemon). BMI showed a genetic correlation only with bread and butter intake in girls.

CONCLUSION

The magnitude of genetic and environmental influences on children's 24-h food and beverage intake differed for boys and girls, which suggests sex differences in the development of eating patterns. Heritability estimates were generally large, although other eating phenotypes may be necessary for identifying genetic correlations with adiposity.

Short-term dietary compensation in free-living adults

Evidence suggests that compensatory behaviors operate in infants and pre-school children, such that the high variance characteristic of single eating occasions is much reduced over the day. However, the concept has not been fully explored in adults. The present within-subject, observational study investigated short-term dietary compensation patterns in fifty, weight-stable, normal weight (n=27), overweight (n=14), and obese (n=9) free-living adults (11 M, 39 F; age 30+/-11 y; BMI 26.3+/-5.9). Twenty four-hour diet recalls were obtained for 7 consecutive days, by the multi-pass technique. Each 24-h period was divided into 7 eating occasions. The coefficient of variation for energy intake was calculated for each adult, for each eating occasion, and over each 24-h period. Sub-group variability was assessed by BMI and frequency of consumption of sweetened energy-yielding beverages. The mean coefficient of variation for energy intake for the 7 eating occasions was 110.5%, compared to 28.9% for the day as a whole. Correlations between energy intakes at successive eating events were uniformly negative. No significant differences were noted in the sub-group analyses. Significantly greater variation in energy intake was noted for snacks compared to meals (P<0.0001). These data suggest that adults regulate energy intake over a 24-h period more closely than they do at individual eating occasions, similar to the pattern previously observed in children. Further studies of compensatory responses by larger sub-groups of individuals at risk for weight gain are warranted.

A short history of beverages and how our body treats them

Numerous studies have demonstrated that beverages containing sugar, high fructose corn syrup (HFCS) or alcohol are handled differently by the body than when sugar or HFCS are incorporated in solid foods and as a result the overall caloric intake from solid food does not adjust to account for the calories in these beverages. A consideration of our evolutionary history may help to explain our poor compensatory response to calories from fluids. This paper reviews the history of eight important beverages: milk, beer, wine, tea, coffee, distilled alcoholic beverages, juice and soft drinks. We arrive at two hypotheses. First, humans may lack a physiological basis for processing carbohydrate or alcoholic calories in beverage because only breast milk and water were available for the vast majority of our evolutionary history. Alternatives to those two beverages appeared in the human diet no more than 11,000 years ago, but Homo sapiens evolved between 100,000 and 200,000 years ago. Second, carbohydrate and alcohol-containing beverages may produce an incomplete satiation sequence which prevents us from becoming satiated on these beverages.