Package Unit Size and Amount of Food: Do Both Influence Intake?

Objective: Large portions increase intake and are hypothesized to contribute to the obesity epidemic. However, it is unclear if portion size affects intake through changes in the unit size of available food or the overall amount of food available for consumption. Thus, this study examined the independent effects of package unit size and amount of food on intake. It was hypothesized that both variables would influence intake. Research Methods and Procedures: Non‐obese (BMI <30 kg/m²), non‐smoking, unrestrained, college‐aged men (n = 12) and women (n = 16) who regularly consumed (≥3 times/wk) snack foods were randomly assigned to one of four groups crossing package unit size (small vs. large) and amount of food (small vs. large). Participants were given a box with 4 snack foods (potato chips, cheese crackers, cookies, and candy) packaged according to their assigned group to take home and eat over 3 days. Dependent variables were energy and gram intake of provided snack foods. Results: An effect of amount of food was found (p < 0.01). A 100% increase in the amount of food provided produced an 81% increase in energy consumed from the snack foods [small amount, 21,037.6 ± 10,852 kJ (5028 ± 2596 kcal) vs. large amount, 11,640.7 ± 4914.1 kJ (2782 ± 1174 kcal)]. No effect of package unit size was found. Discussion: These results suggest that the amount of food available to eat strongly influences intake.     

Weight maintenance 2 years after participation in a weight loss program promoting low-energy density foods

Objective: Observational study designed to determine weight outcomes and associated dietary intake patterns for a sample of participants ≥1 year after completing the University of Alabama at Birmingham EatRight Weight Management Program. Research Methods and Procedures: Seventy‐four former participants (64% women) completed follow‐up visits ≥1 year after participating in EatRight, which promotes low‐energy density, high‐complex carbohydrate foods. Weight maintenance was defined as gaining <5% of body weight since completion of the EatRight program and staying below their program entry weight. Those who gained ≥5% of their body weight since completion were classified as gainers. Results: During EatRight, participants of the follow‐up study lost an average of 4.0 kg. After a mean follow‐up time of 2.2 years, the average weight change was +0.59 kg (mean BMI, 32.5 kg/m²). Seventy‐eight percent of participants gained <5% of their body weight; 46% had no weight regain or continued weight loss. Unadjusted mean intake for maintainers was 1608 kcal, whereas calorie intake for gainers was 1989 kcal. Despite eating slightly fewer calories (adjusted difference, 244; p = 0.058), maintainers ate a similar amount of food, resulting in a lower energy‐density pattern (p = 0.016) compared with those who regained ≥5% of body weight. Gainers also reported consuming larger portions of several food groups. Discussion: Our results indicate that low‐energy‐density eating habits are associated with long‐term weight maintenance. Those who maintain weight after the EatRight program consume a low‐energy‐density dietary pattern and smaller portions of food groups potentially high in energy density than those who regain weight.     

Chefs' opinions of restaurant portion sizes

Objectives: The objectives were to determine who establishes restaurant portion sizes and factors that influence these decisions, and to examine chefs’ opinions regarding portion size, nutrition information, and weight management. Research Methods and Procedures: A survey was distributed to chefs to obtain information about who is responsible for determining restaurant portion sizes, factors influencing restaurant portion sizes, what food portion sizes are being served in restaurants, and chefs’ opinions regarding nutrition information, health, and body weight. The final sample consisted of 300 chefs attending various culinary meetings. Results: Executive chefs were identified as being primarily responsible for establishing portion sizes served in restaurants. Factors reported to have a strong influence on restaurant portion sizes included presentation of foods, food cost, and customer expectations. While 76% of chefs thought that they served “regular” portions, the actual portions of steak and pasta they reported serving were 2 to 4 times larger than serving sizes recommended by the U.S government. Chefs indicated that they believe that the amount of food served influences how much patrons consume and that large portions are a problem for weight control, but their opinions were mixed regarding whether it is the customer's responsibility to eat an appropriate amount when served a large portion of food. Discussion: Portion size is a key determinant of energy intake, and the results from this study suggest that cultural norms and economic value strongly influence the determination of restaurant portion sizes. Strategies are needed to encourage chefs to provide and promote portions that are appropriate for customers’ energy requirements.     

Effect of increased dairy consumption on appetitive ratings and food intake

Objective: The influence of dairy product consumption on food intake and appetitive sensations was explored in a cross‐over design study with individuals who were habitually low (<1 serving/d) or high (>3 servings/d) dairy consumers. Research Methods and Procedures: Fifty‐eight participants were required to eat one portion of dairy each day (low dairy) or three portions of dairy each day (high dairy) for 7 days. After a 7‐day washout period, the opposite treatment condition was completed. Food intake and appetitive ratings were measured on each day of the treatment periods. Results: During the high‐dairy period, participants consumed 209 kcal/d more than during the low dairy period (p < 0.05). There were no significant differences in subjective appetite ratings. Habitual dairy use did not influence either the appetitive or dietary findings. Discussion: These data indicate that increasing dairy consumption may lead to increased energy intake, which could potentially cause weight gain.     

Increased Portion Size Leads to Increased Energy Intake in a Restaurant Meal

Objective: Eating frequently in restaurants is one of the behaviors associated with obesity. This study examined whether increasing the portion size of an entrée affected energy intake at a restaurant meal. Research Methods and Procedures: In a cafeteria‐style restaurant on different days, the size of a pasta entrée was varied from a standard portion (248 g) to a large portion (377 g). The entrée price was not changed. Intake of the entrée was determined by covertly weighing each dish before and after the meal; intake of all other foods was determined by estimating the percent consumed. The 180 adult customers who purchased the entrée also completed a survey in which they rated characteristics of the meal, including the appropriateness of the entrée portion size and the amount that they ate compared with their usual meal. Results: Portion size had a significant effect on intake of the entrée (p < 0.0001). Compared with customers who purchased the standard portion, those who purchased the larger portion increased their energy intake of the entrée by 43% (719 kJ; 172 kcal) and of the entire meal by 25% (664 kJ; 159 kcal). There was no difference between the two groups of customers in ratings of the appropriateness of the portion size or of the amount that was eaten in relation to their usual meal. Discussion: In a restaurant setting, increasing the size of an entrée results in increased energy intake. These results support the suggestion that large restaurant portions may be contributing to the obesity epidemic.     

Physical activity patterns during weight maintenance following a low-energy density dietary intervention

Objective: The objective was to determine the role of physical activity (PA) and energy intake on weight maintenance among former University of Alabama at Birmingham EatRight Weight Management Program participants. Research Methods and Procedures: Eighty‐nine former participants completed follow‐up visits ≥1 year after completing EatRight. BMI was calculated using measured height and weight. Diet intake was estimated from 4‐day food records. PA was assessed using a module from the Behavioral Risk Factor Surveillance System Survey. Cut‐off points were chosen based on the distribution of minutes of activity. For moderate and total activity, cut‐off points were 0, 1 to 30, 31 to 60, and >60 minutes. For vigorous activity, the categories were 0, 1 to 20, 21 to 30, and >30 minutes. General linear models determined the association of PA with change in weight at follow‐up controlling for gender and total energy intake (kcal/d). Results: At follow‐up, 80% (n = 71) of participants maintained (regained <5% of program end weight) their body weight and 20% had gained weight. Mean weight change was 1.0 ± 6.5 kg. Maintainers consumed 384 fewer kcal/d on average. Maintainers had a lower energy density dietary pattern (1.58 vs. 2.01 kcal/g, p < 0.01). There was no significant difference in PA min/d reported by maintainers and gainers. Discussion: Our results suggest that, despite being minimally active, weight‐reduced individuals can successfully maintain their newly achieved body weight with appropriate caloric intake. Adopting a lower calorie, low energy density dietary pattern may reduce the amount of PA that is truly necessary for weight maintenance.     

How Many Calories Are on Our Plate? Expected Fullness,Not Liking,Determines Meal‐size Selection

The availability of highly palatable food is thought to stimulate the selection of larger meals (leading to weight gain and obesity). In this article, we explore aspects of this proposition. Specifically, we scrutinize two basic assumptions: (i) palatable energy‐dense foods are more rewarding (desired), and (ii) these palatable foods are selected in relatively larger portions. In combination with palatability, we also consider the relative role for “expected satiation”—the extent to which a food is expected to deliver satiation. A total of 17 commonly consumed foods were assessed by 28 normal‐weight participants at lunchtime. Critically, our measure of food reward and expected satiation involves comparisons between foods based on equicaloric portions. When assessed in this way, we find that food reward and ideal portion sizes (in kcal) are both closely associated with expected satiation, but not with “expected liking.” Low expected satiation (not expected liking) predicts the selection of large portion sizes (in kcal) and foods with this characteristic tend to be more energy dense and are regarded as less (not more) rewarding (when compared calorie for calorie). Together, these findings challenge the role of palatability in meal‐size selection and they highlight the importance of expected satiation, a “nonaffective” component of food reward.     

High Dietary Calcium Reduces Body Fat Content,Digestibility of Fat,and Serum Vitamin D in Rats

Objective: This study investigated which aspect of energy balance was responsible for the decrease in body fat content of rats fed a high‐calcium, high—dairy protein diet. Research Methods and Procedures: Male Wistar rats were fed a control diet (25% kcal fat, 14% kcal protein from casein, 0.4% by weight calcium) or high‐calcium diet (25% kcal fat, 7% kcal protein from nonfat dry milk, 7% kcal protein from casein, 2.4% calcium) for 85 days. Body weights, digestible energy intakes, energy expenditures, rectal temperatures, body composition, and serum glucose, insulin, free fatty acids, triglycerides, and 1, 25‐dihydroxyvitamin D were measured. Results: Rats fed high‐calcium diet gained significantly less weight than controls and had 29% less carcass fat. Gross energy intake was not significantly different between groups, but digestible energy was 90% of gross energy in the high‐calcium diet compared with 94% in the control diet because of increased fecal excretion of dietary lipid. The difference in digestible energy intake accounted for differences in carcass energy. Body temperatures and energy expenditures of the rats were not different. The high‐calcium diet reduced serum triglycerides by 23% and serum 1, 25‐dihydroxyvitamin D by 86%. Discussion: These results confirm that a high‐calcium diet decreases body weight and fat content due to a lower digestible energy intake caused by increased fecal lipid and a nonsignificant reduction in gross energy intake.     

Energy imbalance underlying the development of childhood obesity

Objective: To develop a model based on empirical data and human energetics to predict the total energy cost of weight gain and obligatory increase in energy intake and/or decrease in physical activity level associated with weight gain in children and adolescents. Research Methods and Procedures: One‐year changes in weight and body composition and basal metabolic rate (BMR) were measured in 488 Hispanic children and adolescents. Fat‐free mass (FFM) and fat mass (FM) were measured by DXA and BMR by calorimetry. Model specifications include the following: body mass (BM) = FFM + FM, each with a specific energy content, cff (1.07 kcal/g FFM) and cf (9.25 kcal/g FM), basal energy expenditure (EE), kff and kf, and energetic conversion efficiency, eff (0.42) for FFM and ef (0.85) for FM. Total energy cost of weight gain is equal to the sum of energy storage, EE associated with increased BM, conversion energy (CE), and diet‐induced EE (DIEE). Results: Sex‐ and Tanner stage–specific values are indicated for the basal EE of FFM (kff) and the fat fraction in added tissue (fr). Total energy cost of weight gain is partitioned into energy storage (24% to 36%), increase in EE (40% to 57%), CE (8% to 13%), and DIEE (10%). Observed median (10th to 90th percentile) weight gain of 6.1 kg/yr (2.4 to 11.4 kg/yr) corresponds at physical activity level (PAL) = 1.5, 1.75, and 2.0 to a total energy cost of weight gain of 244 (93 to 448 kcal/d), 267 (101 to 485 kcal/d), and 290 kcal/d (110 to 527 kcal/d), respectively, and to a total energy intake of 2695 (1890 to 3730), 3127 (2191 to 4335), and 3551 (2487 to 4930) kcal/d, respectively. If weight gain is caused by a change in PAL alone and PAL₀ = 1.5 at baseline t = 0, the model indicates a drop in PAL of 0.22 (0.08 to 0.34) units, which is equivalent to 60 (18 to 105) min/d of walking at 2.5 mph. Discussion: Halting the development or progression of childhood obesity, as observed in these Hispanic children and adolescents, by counteracting its total energy costs will require a sizable decrease in energy intake and/or reciprocal increase in physical activity.     

Effects of Doubling the Portion Size of Fruit and Vegetable Side Dishes on Children's Intake at a Meal

Increasing the portion size of energy‐dense entrées has been shown to increase children's energy intake during a meal. It remains to be investigated whether serving larger portions to children can be used to promote intake of more healthful foods, such as fruits and vegetables (F&V). The aim of the present study was to examine the effects of increasing the portion size of F&V side dishes on children's intake. Forty‐three children (22 boys, 21 girls), aged 5–6 years, were served dinner once a week for 2 weeks. Each dinner consisted of pasta with tomato sauce, three F&V side dishes (broccoli, carrots, and applesauce), and milk. The portion size of the F&V was doubled between experimental conditions whereas the size of the pasta remained constant. Doubling the portion size of the side dishes resulted in a 43% increase in children's intake of the fruit side dish (P = 0.001), but did not affect children's intake of the two vegetable side dishes (P > 0.60). Further, when the portion size of F&V side dishes was doubled, children ate significantly less of the pasta (P = 0.04). The difference in meal energy intake between portion size conditions (19.5 ± 16.3 kcal) was not significant (P = 0.24). Although more studies are needed to understand whether increases in portion size can influence vegetable intake, children did eat more in response to a large quantity of a preferred low energy‐dense fruit side dish at meals. Thus variations in portion size can be used strategically to help children achieve the recommended intake of fruits.     

Energy Intake and Meal Portions: Associations with BMI Percentile in U.S. Children

Objective: We examined relationships of eating patterns and reported energy intake (rEI) with BMI percentile in U.S. children. Research Methods and Procedures: Two 24‐hour dietary recalls from the Continuing Surveys of Food Intakes by Individuals 1994 to 1996 and 1998 (1005 boys, 990 girls) were averaged, and children were categorized into three age groups: 3 to 5 years (n = 1077), 6 to 11 years (n = 537), and 12 to 19 years (n = 381). Physiologically implausible reports due to reporting bias or abnormal intake (rEI outside ±18% to 23% of predicted energy requirements; pER) were identified. Results: rEI averaged 109 ± 34% and 100 ± 10% of pER in the total and plausible samples, respectively. EI was overreported more in younger children and underreported more in overweight older children. Children with plausible rEI (45.3% of sample) averaged 4.7 eating occasions/d, 589 kcal/meal, 223 kcal/snack, and 2038 kcal/d. rEI was not associated with BMI percentile in the total sample. In the plausible sample, rEI, meal portion size, and meal energy were positively associated with BMI percentile in boys 6 to 11 years and in children 12 to 19 years. No relationships were found in children 3 to 5 years and girls 6 to 11 years. Relationships were more consistent and stronger in the plausible compared with the total sample. Discussion: Excluding implausible dietary reports may be necessary for discerning dietary associations with BMI percentile. EI and meal, but not snack, patterns may play a quantitatively greater role in weight regulation as children age.     

Increasing healthy eating vs. reducing high energy-dense foods to treat pediatric obesity

Objective: The objective was to compare targeting increased eating of healthy foods vs. reducing intake of high energy‐dense foods within the context of a family‐based behavioral weight control program. Methods and Procedures: Forty‐one 8–12 year‐old children >85th BMI percentile were randomly assigned to a 24‐month family‐based behavioral treatment that targeted increasing fruits and vegetables and low‐fat dairy vs. reducing intake of high energy‐dense foods. Results: Children in the increase healthy food group showed greater reduction in zBMI compared to children in the reduce high energy‐dense food group at 12‐ (?0.30 zBMI units vs. ?0.15 zBMI units, P = 0.01) and 24‐ (?0.36 zBMI units vs ?0.13 zBMI units, P = 0.04) month follow‐up. Parents in the increase healthy food group showed greater reductions in concern about child weight (P = 0.007), and these changes were associated with child zBMI change (P = 0.008). Children in the reduce high energy‐dense group showed larger sustained reductions in high energy‐dense foods (P < 0.05). Baseline levels of high energy‐dense foods (P < 0.05), parent food restraint (P = 0.01), parent concern over parent weight (P = 0.01) and parent acceptance of the child (P < 0.05) moderated child zBMI change, with greater sustained reductions in zBMI for children in the increase healthy food group for each measure. Parent zBMI change followed the same pattern as child changes, and parent and child zBMI changes were correlated (P < 0.001). Discussion: Focusing on healthy food choices within an energy restricted diet may be useful in family‐based weight control programs.     

Pramlintide treatment reduces 24-h caloric intake and meal sizes and improves control of eating in obese subjects: a 6-wk translational research study

Evidence from rodent studies indicates that the beta-cell-derived neurohormone amylin exerts multiple effects on eating behavior, including reductions in meal size, intake of highly palatable foods, and stress-induced sucrose consumption. To assess the effect of amylin agonism on human eating behavior we conducted a randomized, blinded, placebo-controlled, multicenter study investigating the effects of the amylin analog pramlintide on body weight, 24-h caloric intake, portion sizes, "fast food" intake, and perceived control of eating in 88 obese subjects. After a 2-day placebo lead-in, subjects self-administered pramlintide (180 microg) or placebo by subcutaneous injection 15 min before meals for 6 wk without concomitant lifestyle modifications. Compared with placebo, pramlintide treatment elicited significant mean reductions from baseline in body weight on day 44 (-2.1 +/- 0.3 vs. +0.1 +/- 0.4%, P < 0.001), 24-h caloric intake (-990 +/- 94 vs. -243 +/- 126 kcal on day 3, P < 0.0001; -680 +/- 86 vs. -191 +/- 161 kcal on day 43, P < 0.01), portion sizes, and caloric intake at a "fast food challenge" (-385 +/- 61 vs. -109 +/- 88 kcal on day 44, P < 0.05). Pramlintide treatment also improved perceived control of eating, as demonstrated by a 45% placebo-corrected reduction in binge eating scores (P < 0.01). The results of this translational research study confirm in humans various preclinical effects of amylin agonism, demonstrating that pramlintide-mediated weight loss in obese subjects is accompanied by sustained reductions in 24-h food intake, portion sizes, fast food intake, and binge eating tendencies.     

Effects of age on children's intake of large and self-selected food portions

Objective: Whether developmental periods exist in which children become particularly sensitive to environmental influences on eating is unclear. This research evaluated the effects of age on intake of large and self‐selected portions among children 2 to 9 years of age. Research Methods and Procedures: Seventy‐five non‐Hispanic white children 2 to 3, 5 to 6, and 8 to 9 years of age were seen at a dinner meal in reference, large, and self‐selected portion size conditions in which the size of an entrée was age‐appropriate, doubled, and determined by the child, respectively. Weighed food intake data were collected. Entrée bite size and bite frequency were assessed. Height and weight measurements were obtained. Results: The effect of age on children's intake of the large portion was not significant. Entrée consumption was 29% greater (p < 0.001) and meal energy intake was 13% greater (p < 0.01) in the large portion condition than in the reference condition. Increases in entrée consumption were attributable to increases in average bite size (p < 0.001). Neither child weight nor maternal weight predicted children's intake of large portions. Self‐selection resulted in decreased entrée (p < 0.05) and meal energy (p < 0.01) only among those children who ate more when served the large portion. Discussion: The results of this research confirm that serving large entrée portions promotes increased intake at meals among 2‐ to 9‐year‐old children. These findings suggest that any age‐related differences in children's response to large portions are likely to be smaller than previously suspected.     

Dietary fat increases energy intake across the range of typical consumption in the United States

Objective: The fat content of a diet has been shown to affect total energy intake, but controlled feeding trials have only compared very high (40% of total calories) fat diets with very low (20% of total calories) fat diets. This study was designed to measure accurately the voluntary food and energy intake over a range of typical intake for dietary fat. Methods and Procedures: Twenty‐two non‐obese subjects were studied for 4 days on each of three diets, which included core foods designed to contain 26, 34, and 40% fat, respectively of total calories and ad lib buffet foods of similar fat content. All diets were matched for determinants of energy density except dietary fat. Subjects consumed two meals/day in an inpatient unit and were provided the third meal and snack foods while on each diet. All food provided and not eaten was measured by research staff. Results: Voluntary energy intake increased significantly as dietary fat content increased (P = 0.008). On the 26% dietary fat treatment, subjects consumed 23.8% dietary fat (core and ad lib foods combined) and 2,748 ± 741 kcal/day (mean ± s.d.); at 34% dietary fat, subjects consumed 32.7% fat and 2,983 ± 886 kcal/day; and at 40% dietary fat subjects consumed 38.1% fat and 3,018 ± 963 kcal/day. Discussion: These results show that energy intake increases as dietary fat content increases across the usual range of dietary fat consumed in the United States. Even small reductions in dietary fat could help in lowering total energy intake and reducing weight gain in the population.     

Trends and dietary determinants of overweight and obesity in a multiethnic population

Objectives : To describe trends in BMI among different ethnic groups in Hawaii and to explore the relation of nutrient and food intake with excess weight. Research Methods and Procedures : We pooled demographic, anthropometric, and nutritional data derived from a detailed diet history for 159, 683 participants of 18 population‐based epidemiological studies conducted in Hawaii over a 25‐year period. The age‐adjusted prevalence of excess weight (BMI ≥ 25 kg/m²) was estimated for 5‐year intervals. To explore dietary determinants of excess weight, we computed odds ratios using logistic regression. Results : During the study period, the prevalence of excess weight increased considerably among all ethnic groups. Native Hawaiians had the highest and Asian Americans had the lowest prevalence of excess weight at all times. Although the percentage of calories consumed from carbohydrates increased, the percentage of calories from fat decreased over time. On an individual level, fat and protein consumption predicted a higher BMI, and dietary fiber intake predicted a lower BMI. Similarly, a higher consumption of meat, poultry, and fish was related to excess weight, whereas fruit and vegetable intake were inversely associated with excess weight. After stratification by ethnicity, the associations were not materially altered among women, but carbohydrates seemed to have a stronger association with excess weight among Native Hawaiian and Japanese men than among white men. Discussion : In this large ethnically diverse population, plant‐based foods and dietary fiber emerged as a potential protective factor against excess weight regardless of ethnicity.     

Understanding reporting bias in the dietary recall data of 11-year-old girls

Objective: This study describes patterns of bias in self‐reported dietary recall data of girls by examining differences among girls classified as under‐reporters, plausible reporters, and over‐reporters on weight, dietary patterns, and psychosocial characteristics. Research Methods and Procedures: Participants included 176 girls at age 11 and their parents. Girls’ weight and height were measured. Three 24‐hour dietary recalls and responses to psychosocial measures were collected. Plausibility cut‐offs for reported energy intake as a percentage of predicted energy requirements were used to divide the sample into under‐reporters, plausible reporters, and over‐reporters. Differences among these three groups on dietary and psychosocial variables were assessed to examine possible sources of bias in reporting. Results: Using a ±1 standard deviation cut‐off for energy intake plausibility, 50% of the sample was categorized as plausible reporters, 34% as under‐reporters, and 16% as over‐reporters. Weight status of under‐reporters was significantly higher than that of plausible reporters and over‐reporters. With respect to reported dietary intake, under‐reporters were no different from plausible reporters on intakes of foods with higher nutrient densities and lower energy densities and were significantly lower than plausible reporters on intakes of foods with lower nutrient densities and higher energy densities. Over‐reporters reported significantly higher intakes of all food groups and the majority of subgroups, relative to plausible reporters. Under‐reporters had significantly higher levels of weight concern and dietary restraint than both plausible reporters and over‐reporters. Discussion: Techniques to categorize plausible and implausible reporters can and should be used to provide an improved understanding of the nature of error in children's dietary intake data and account for this error in analysis and interpretation.     

Identifying the Energy Gap: Magnitude and Determinants of 5‐Year Weight Gain in Midage Women

Objective: The aims of this study were to estimate average yearly weight gain in midage women and to identify the determinants of weight gain and gaining weight at double the average rate. Research Methods and Procedures: The study sample comprised 8071 participants (45 to 55 years old) in the Australian Longitudinal Study on Women's Health who completed mailed surveys in 1996, 1998, and 2001. Results: On average, the women gained almost 0.5 kg per year [average 2.42 kg (95% confidence interval, 2.29 to 2.54) over 5 years]. In multivariate analyses, variables associated with energy balance (physical activity, sitting time, and energy intake), as well as quitting smoking, menopause/hysterectomy, and baseline BMI category were significantly associated with weight gain, but other behavioral and demographic characteristics were not. After adjustment for all of the other biological and behavioral variables, the odds of gaining weight at about twice the average rate (>5 kg over 5 years) were highest for women who quit smoking (odds ratio = 2.94; 95% confidence interval, 2.17, 3.96). There were also independent relationships between the odds of gaining >5 kg and lower levels of habitual physical activity, more time spent sitting, energy intake (but only in women with BMI > 25 at baseline), menopause transition, and hysterectomy. Discussion: The average weight gain equates with an energy imbalance of only about 10 kcal or 40 kJ per day, which suggests that small sustained changes in the modifiable behavioral variables could prevent further weight gain.     

Amount of Food Group Variety Consumed in the Diet and Long‐Term Weight Loss Maintenance

Objective: Decreases in variety of foods consumed within high‐fat‐dense food groups and increases in variety of foods consumed within low‐fat‐dense food groups are associated with lower energy intake and greater weight loss during obesity treatment and may assist with weight loss maintenance. This study examined food group variety in 2237 weight loss maintainers in the National Weight Control Registry, who had lost 32.2 ± 18.0 kg (70.9 ± 39.5 lbs) and maintained a weight loss of at least 13.6 kg (30 lbs) for 6.1 ± 7.7 years. Research Methods and Procedures: At entry into the registry, registry members completed a food frequency questionnaire from which amount of variety consumed from different food groups was assessed. To provide a context for interpreting the level of variety occurring in the diet of registry participants, food group variety was compared between registry participants and 96 individuals who had recently participated in a behavioral weight loss program and had lost at least 7% of initial body weight. Results: Registry members reported consuming a diet with very low variety in all food groups, especially in those food groups higher in fat density. Registry participants consumed significantly (p < 0.001) less variety within all food groups, except fruit and combination foods, than recent weight losers after 6 months of weight loss treatment. Discussion: These results suggest that successful weight loss maintainers consume a diet with limited variety in all food groups. Restricting variety within all food groups may help with consuming a low‐energy diet and maintaining long‐term weight loss.     

Pre-meal water consumption reduces meal energy intake in older but not younger subjects

Objective: To determine whether the consumption of water 30 minutes before an ad libitum meal reduces meal energy intake in young and older adults. Research Methods and Procedures: Healthy, non‐obese young (n = 29; age, 21 to 35 years) and older (n = 21; age, 60 to 80 years) individuals were provided with an ad libitum lunch meal on two occasions. Thirty minutes before the lunch meals, subjects were given either a water preload (WP: 375 mL, women; 500 mL, men) or no preload (NP). Energy intake at the two lunch meals was measured. Visual analog scales were used to assess changes in hunger, fullness, and thirst during the meal studies. Results: There was no significant difference in meal energy intake between conditions in the young subjects (892 + 51 vs. 913 ± 54 kcal for NP and WP, respectively; p = 0.65). However, meal energy intake after the WP was significantly reduced relative to the NP condition in the older subjects (682 + 53 vs. 624 ± 56 kcal for NP and WP, respectively; p = 0.02). This effect was caused primarily by the reduction in meal energy intake after water consumption in older men. Hunger ratings were lower and fullness ratings were higher in older compared with younger adults (p < 0.01). Fullness ratings were higher in the WP condition compared with the NP condition for all subjects (p = 0.01). No age differences in thirst were detected during the test meals. Discussion: Under acute test meal conditions, pre‐meal water consumption reduces meal energy intake in older but not younger adults. Because older adults are at increased risk for overweight and obesity, intervention studies are needed to determine whether pre‐meal water consumption is an effective long‐term weight management strategy for the aging population.