A Worksite Program for Overweight Middle-Aged Men Achieves Lesser Weight Loss With Exercise Than With Dietary Change

Objective To compare changes in total and regional body composition using dual energy X-ray absorptiometry (DEXA) after subjects lost weight through change in diet or exercise.Design A 12-month, randomized, controlled study of two weight-loss interventions — low-fat diet ad libitum or moderate, unsupervised exercise — in free-living, middle-aged men. Compliance was determined at monthly measurement sessions through food records and activity logs; DEXA scans were performed every 3 months.Subjects/setting Fifty-eight overweight men (mean body mass INDEX=29.0±2.6; mean AGE=43.4±5.7 years) recruited from a national corporation were assigned randomly to diet, exercise, or control groups.Interventions One group reduced dietary fat to 26.4% of energy intake but kept activity unchanged; another group self-selected aerobic exercise (three sessions per week at 65% to 75% maximum heart rate) but kept diet unchanged. A control group maintained weight.Main outcome measures At 12 months, measurements of weight, total and regional fat mass and lean mass, energy intake, and percentage dietary fat; physical activity indexes. Statistical analyses Results were analyzed using paired t tests and analysis of variance.Results Mean weight loss was 6.4±3.3 kg in dieters and 2.6+3.0 kg in exercisers; control subjects maintained weight. DEXA scans revealed that 40% of dieters’ weight loss was lean tissue; more than 80% of weight lost by exercisers was fat. Exercisers maintained limb lean tissue and lost fat mass.Conclusions Greater total weight and lean tissue loss occurred when subjects lost weight through a low-fat diet consumed ad libitum than when subjects participated in unsupervised aerobic exercise. Use of DEXA enabled identification of progressive total and regional changes in fat and lean tissue. J Am Diet Assoc. 1997; 97:37–42.     

A Low-Fat Intake and Greater Activity Level are Associated With Lower Weight Regain 3 Years After Completing a Very–Low-Calorie Diet

Objective To examine the roles of diet, exercise, and lifestyle factors in determining long-term weight regain after weight loss with a very–low-calorie diet (VLCD).Subjects Twenty-seven of 38 women who lost weight with a VLCD.Design Graduates of a weight loss intervention study returned for follow-up 3 years after program completion. Percentage of initial weight loss that was regained was correlated with subjects’ fat intake (assessed via 7-day food records and a Diet Habit Survey), energy intake (assessed via 7-day food records), activity level and lifestyle factors (assessed via questionnaires) that are supportive of weight loss maintenance.Statistical analyses performed Regression analysis was used to assess the relationship of weight regain with fat intake, activity level, and energy intake. Contingency table analysis was used to assess the association between weight regain and lifestyle factors.Results Subjects followed experienced a −20.7 kg±9.2 kg (−19.2%±7%) (mean±standard deviation) weight change during the original VLCD program and a 13.9 kg±11.3 kg (76.6%±52.1%) weight change 3 years post-VLCD. Fat intake, assessed by a 7-day food diary, was positively correlated with weight regain at 3 years (r=0.66, P=.0004). Less weight regain was also seen with a lower percent fat intake as reflected by a higher Diet Habit Survey score (r=−0.55, P=.004). Women with the lowest tertile of reported fat intake (<25% of energy) from the Diet Habit Survey regained the least amount of weight (P=.05). Activity level was negatively correlated with weight regain (r=−0.53, P=.005). After correction for multiple comparisons, there was no association between total energy intake and weight regain. Lifestyle factors were also not associated with weight regain.Applications/conclusions Identifying strategies to maintain weight loss is crucial because of the negative health effects and increasing prevalence of obesity. For women who have lost weight on a VLCD, limiting dietary fat intake and maintaining physical activity are both important factors for the prevention of weight regain. To promote better weight loss outcomes, registered dietitians should help clients who have lost weight limit their fat intake to less than 30% of energy and encourage high activity levels. J Am Diet Assoc. 2002;102:1252–1256.     

Athletes' dietary intake was closer to French RDA's than those of young sedentary counterparts

It has been demonstrated that athletes' dietary intake was relatively well-balanced according to the recommended dietary allowances (RDAs). In contrast, other studies have shown that athletes may have low energy intake or imbalance of protein and fat and insufficient minerals and vitamins. Nonetheless, we hypothesized that practicing a sport may allow young adults to have a nutritional status closer to recommended values. The purpose of this experiment was to study the nutritional status of young French adults, particularly to compare the nutritional status of trained young male and female athletes to those of young sedentary control subjects, and to national RDAs. A total of 85 young adults were recruited and filled a 4-day food and physical activity record. Dietary intake, energy expenditure, energy balance, carbohydrate, protein, fat, water, vitamins, and minerals were recorded. Data were analyzed with a software Nutrilog and statistics with Sigma Stat. Energy intake values were 9874 ± 3050 kJ for the athletes and 7506 ± 1845 kJ for control subjects. Athletes' nutritional status was closer to French RDAs than those of sedentary subjects who present a lower energy intake, a greater percentage of the energy intake from fat and lower values for minerals and vitamins. In conclusion, practicing a sport may allow athletes to balance their energy intake and expenditure and could be a good way to have a nutritional status closer to RDAs. Educational programs for students on proper food selection, eating habits and physical activity are needed to improve the nutritional status of these young French adults, particularly in sedentary students.     

Dietary energy density in the treatment of obesity: a year-long trial comparing 2 weight-loss diets

BACKGROUND: Consuming foods low in energy density (kcal/g) decreases energy intake over several days, but the effectiveness of this strategy for weight loss has not been tested. OBJECTIVE: The effects on weight loss of 2 strategies for reducing the energy density of the diet were compared over 1 y. DESIGN: Obese women (n = 97) were randomly assigned to groups counseled either to reduce their fat intake (RF group) or to reduce their fat intake and increase their intake of water-rich foods, particularly fruit and vegetables (RF+FV group). No goals for energy or fat intake were assigned; the subjects were instructed to eat ad libitum amounts of food while following the principles of their diet. RESULTS: After 1 y, study completers (n = 71) in both groups had significant decreases in body weight (P < 0.0001). Subjects in the RF+FV group, however, had a significantly different pattern of weight loss (P = 0.002) than did subjects in the RF group. After 1 y, the RF+FV group lost 7.9 +/- 0.9 kg and the RF group lost 6.4 +/- 0.9 kg. Analysis of all randomly assigned subjects also showed a different pattern of weight loss between groups (P = 0.021). Diet records indicated that both groups had similar reductions in fat intake. The RF+FV group, however, had a lower dietary energy density than did the RF group (P = 0.019) as the result of consuming a greater weight of food (P = 0.025), especially fruit and vegetables (P = 0.037). The RF+FV group also reported less hunger (P = 0.003). CONCLUSION: Reducing dietary energy density, particularly by combining increased fruit and vegetable intakes with decreased fat intake, is an effective strategy for managing body weight while controlling hunger.     

Diet intervention methods to reduce fat intake: nutrient and food group composition of self-selected low-fat diets

A multicentered pilot study was conducted to test an intervention protocol designed to reduce fat intake to 15% of energy intake. Eligible subjects were postmenopausal women with stage II breast cancer whose baseline fat intake was more than 30% of energy intake. The low-fat diet intervention protocol consisted of bi-weekly individual counseling sessions with emphasis on substitution of lower-fat foods for high-fat foods and maintenance of nutritional adequacy. Nutrient intakes were calculated from 4-day food records collected at baseline and after 3 months of diet intervention. Mean daily fat intake for the 17 patients on the low-fat diet dropped significantly from 38.4 +/- 4.3% of energy intake at baseline to 22.8 +/- 7.8% at 3 months (p less than .001). A 25% reduction in mean energy intake, from 1,840 +/- 419 kcal at baseline to 1,365 +/- 291 kcal at 3 months, was accompanied by significant increases in protein and carbohydrate as percent of energy intake. A mean weight loss of 2.8 kg and a 7.7% reduction in serum cholesterol were observed; both changes were significant at the p less than .01 level. Absolute intakes of zinc and magnesium were significantly reduced. However, mean intake on the low-fat diet for 14 vitamins and minerals, including zinc and magnesium, exceeded two-thirds of the 1989 Recommended Dietary Allowances (RDAs). When expressed as nutrient density (i.e., amount of nutrient per 1,000 kcal), increases were observed for all micronutrients. These results support the hypothesis that a nutritionally adequate low-fat diet can be successfully implemented in a highly motivated, free-living population.     

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.     

A low-fat intake and greater activity level are associated with lower weight regain 3 years after completing a very-low-calorie diet

OBJECTIVE: To examine the roles of diet, exercise, and lifestyle factors in determining long-term weight regain after weight loss with a very-low-calorie diet (VLCD). SUBJECTS: Twenty-seven of 38 women who lost weight with a VLCD. DESIGN: Graduates of a weight loss intervention study returned for follow-up 3 years after program completion. Percentage of initial weight loss that was regained was correlated with subjects' fat intake (assessed via 7-day food records and a Diet Habit Survey), energy intake (assessed via 7-day food records), activity level and lifestyle factors (assessed via questionnaires) that are supportive of weight loss maintenance. STATISTICAL ANALYSES PERFORMED: Regression analysis was used to assess the relationship of weight regain with fat intake, activity level, and energy intake. Contingency table analysis was used to assess the association between weight regain and lifestyle factors. RESULTS: Subjects followed experienced a -20.7kg+/-9.2kg (-19.2%+/-7%) (mean+/-standard deviation) weight change during the original VLCD program and a 13.9kg+/-11.3kg (76.6%+/-52.1%) weight change 3 years post-VLCD. Fat intake, assessed by a 7-day food diary, was positively correlated with weight regain at 3 years (r=0.66, P=.0004). Less weight regain was also seen with a lower percent fat intake as reflected by a higher Diet Habit Survey score (r=-0.55, P=.004). Women with the lowest tertile of reported fat intake (<25% of energy) from the Diet Habit Survey regained the least amount of weight (P=.05). Activity level was negatively correlated with weight regain (r=-0.53, P=.005). After correction for multiple comparisons, there was no association between total energy intake and weight regain. Lifestyle factors were also not associated with weight regain.Applications/conclusions: Identifying strategies to maintain weight loss is crucial because of the negative health effects and increasing prevalence of obesity. For women who have lost weight on a VLCD, limiting dietary fat intake and maintaining physical activity are both important factors for the prevention of weight regain. To promote better weight loss outcomes, registered dietitians should help clients who have lost weight limit their fat intake to less than 30% of energy and encourage high activity levels.     

Body composition and nutrient intakes of college men and women basketball players

Computer analysis of diet records was used to compare adequacy of nutrient intake for 16 male and 10 female intercollegiate basketball players. Significant differences (p less than .05) between men and women were observed for the provision of nutrients from food alone; mean percent RDAs of all nutrients except vitamins A and D was greater for men. This was due primarily to caloric intakes by the men, which averaged twice those of the women. Nutrient supplements had a significant effect on the women's total intake. With the exceptions of energy, protein, and vitamin C, differences between men and women in percent RDAs were eliminated when the contribution of nutrient supplements was included. The data made apparent the need for dietitians familiar with sports nutrition to counsel female athletes on means of obtaining nutrients via an adequate diet.     

Accuracy of energy intake data estimated by a multiple-pass, 24-hour dietary recall technique

Objective This study examined the accuracy of a multiplepass, 24 hour dietary recall method for estimating energy intakes of men and women by comparing it with energy intake required for weight maintenance.Design Threeday, multiplepass, 24-hour recalls were obtained on randomly selected days during a selfselected diet period when subjects were preparing their own meals and during a controlled diet period when all meals were provided by the study. During the dietary intervention, weight was maintained; body weight and dietary intake were monitored closely, thereby allowing estimation of the energy intake required for weight maintenance.Subjects/setting Seventyeight men and women (22 to 67 years old) from the Dietary Effects on Lipoprotein and Thrombogenic Activity (DELTA) study participated in this study. All 24-hour recalls were collected using a computerassisted, interactive, multiplepass telephone interview technique. Energy requirements for each individual were determined by the energy content of the DELTA study foods provided to maintain weight.Statistical analysis Paired and independent t tests were conducted to examine differences among study variables. Agreement between recalled energy intake and weight maintenance energy intake was analyzed using the BlandAltman technique.Results Compared with weight maintenance energy intake, during the selfselected diet period men and women underestimated energy intake by 11% and 13%, respectively. During the controlled diet period, men underestimated energy intake by 13%, whereas women overestimated energy by 1.3%.Applications/conclusions Men had a tendency to underestimate energy intake irrespective of the recording period. The accuracy of the recalled energy intake of women may be influenced by recording circumstances. Researchers should examine the factors influencing underreporting and overreporting by individuals and their impact on macronutrient and micronutrient intakes. Also, strategies need to be developed to minimize underreporting and overreporting. J Am Diet Assoc. 2000; 100:303-308,311.     

Cross-sectional measurement of nutrient intake among adolescents in 1996

BACKGROUND: Many components are involved in an assessment of diet and health among youth. To address these issues and document the major contributions of fat, fiber, vitamins, and minerals to the diet, we analyzed baseline cross-sectional data from a cohort of 16,882 youth. METHODS: Cross-sectional analyses were conducted on the Growing Up Today Study dietary data reported by 16,882 9- to 14-year-olds in 1996. The adolescent food frequency questionnaire was used to assess this age group's eating habits. Arithmetic means and standard deviations were calculated on energy-adjusted and unadjusted data. RESULTS: Mean intake (including vitamin/mineral supplementation) for all nutrients met 100% of the RDAs, except calcium for girls. Comparing the servings of foods with the USDA Food Pyramid, neither boys nor girls met recommended number of servings except for dairy. Overweight participants consumed fewer kilocalories and lower levels of nutrients than their nonoverweight peers. CONCLUSION: These cross-sectional data from 1996 indicate that this cohort is consuming foods and nutrients comparable with national data of less fat and more carbohydrates in their diet. Overweight participants have similar dietary patterns except for total energy. The cohort's diet (with vitamin/mineral supplementation) is meeting the RDAs, but actual foods consumed suggest a lack of balance in the diet.     

Body weight loss and weight maintenance in relation to habitual caffeine intake and green tea supplementation

OBJECTIVE: Investigation of the effect of a green tea-caffeine mixture on weight maintenance after body weight loss in moderately obese subjects in relation to habitual caffeine intake. RESEARCH METHODS AND PROCEDURES: A randomized placebo-controlled double blind parallel trial in 76 overweight and moderately obese subjects, (BMI, 27.5 +/- 2.7 kg/m2) matched for sex, age, BMI, height, body mass, and habitual caffeine intake was conducted. A very low energy diet intervention during 4 weeks was followed by 3 months of weight maintenance (WM); during the WM period, the subjects received a green tea-caffeine mixture (270 mg epigallocatechin gallate + 150 mg caffeine per day) or placebo. RESULTS: Subjects lost 5.9 +/-1.8 (SD) kg (7.0 +/- 2.1%) of body weight (p < 0.001). At baseline, satiety was positively, and in women, leptin was inversely, related to subjects' habitual caffeine consumption (p < 0.01). High caffeine consumers reduced weight, fat mass, and waist circumference more than low caffeine consumers; resting energy expenditure was reduced less and respiratory quotient was reduced more during weight loss (p < 0.01). In the low caffeine consumers, during WM, green tea still reduced body weight, waist, respiratory quotient and body fat, whereas resting energy expenditure was increased compared with a restoration of these variables with placebo (p < 0.01). In the high caffeine consumers, no effects of the green tea-caffeine mixture were observed during WM. DISCUSSION: High caffeine intake was associated with weight loss through thermogenesis and fat oxidation and with suppressed leptin in women. In habitual low caffeine consumers, the green tea-caffeine mixture improved WM, partly through thermogenesis and fat oxidation.     

Dietary patterns in three English towns in relation to dietary goals and RDAs

The nutrient intakes of 1115 men and 1225 women aged 35–54 years living in three English towns were compared with recommended goal intakes and recommended daily allowances (RDA). The majority of subjects consumed more energy derived from fat, more sugar and less fibre than the goal levels. Less than 2% of subjects in any town or sex were meeting all the dietary goals. A third of the subjects stated that they had changed their diet in the last year. The most common reasons given for dietary change were to improve health and to lose weight. Comparison of nutrient intakes with the RDAs showed that most subjects were consuming levels which met the RDAs, although energy intake in women was low.     

Variability in food consumption patterns of adults in the U.S. population

This study used the 24‐hour dietary recall data of white adult respondents in the NHANES I to demonstrate variability in food consumption patterns among subgroups of this population. Both a quantitative dimension, mean intake levels and the qualitative dimensions of nutrient density and diet diversity were used. Generally males consumed more food energy and nutrients than did females, as did younger, as compared to older subjects. This pattern was less consistent for vitamins A and C than for other nutrients. Sex differences in diet diversity were small. The higher energy and nutrient consumption of males, similarity in the number of “nutritious” foods in the diet and higher nutrient density values found among females, together, support the existence of variability in food consumption.     

Nutritional profile of football athletes eating from a training table

Food consumption of 11 male, intercollegiate football athletes (19.6±0.4 yr old (mean±S.E.), 108.1±2.9 kg BW, 191±1 cm HT) was studied over 3 consecutive weekdays to characterize nutritional intakes relative to food choice behavior. Subjects took all meals from a training table, and they trained 2.0 hr/d. The investigators observed and recorded the kinds and amounts of foods eaten by subjects. Food items from the trayline were weighed. Mean energy intake was 3593±217 kcal/d distributed as 22% protein, 39% fat, and 39% carbohydrate. Total carbohydrate intake (329±12 g/d) and its contribution to energy was less than generally recommended for athletes (500 g/d or 60% kcal). Subjects emphasized meat consumption; meat provided 33% kcal, 63% protein, and 45% fat intake. The overall mean intake of 10 vitamins and minerals exceeded the RDAs, but the intake of magnesium, folacin, and pyridoxine were 70–100% RDA. There were individual instances of marginal intakes (<70% RDA).     

The role of dietary fat in body fatness: evidence from a preliminary meta-analysis of ad libitum low-fat dietary intervention studies

The role of high-fat diets in weight gain and obesity has been questioned because of inconsistent reports in the literature concerning the efficacy of ad libitum low-fat diets to reduce body weight. We conducted a meta-analysis of weight loss occurring on ad libitum low-fat diets in intervention trials, and analysed the relationship between initial body weight and weight loss. We selected controlled trials lasting more than 2 months comparing ad libitum low-fat diets with a control group consuming their habitual diet or a medium-fat diet ad libitum published from 1966 to 1998. Data were included from 16 trials with a duration of 2-12 months, involving 1728 individuals. No trials on obese subjects fulfilled the inclusion criteria. The weighted difference in weight loss between intervention and control groups was 2.55 kg (95% CI, 1.5-3.5; P < 0.0001). Weight loss was positively and independently related to pre-treatment body weight (r = 0.52, P < 0.05) and to reduction in the percentage of energy as fat (0.37 kg/%, P < 0.005) in unweighted analysis. Extrapolated to a BMI of about 30 kg/m2 and assuming a 10% reduction in dietary fat, the predicted weight loss would be 4.4 kg (95% CI, 2.0 to -6.8 kg). Because weight loss was not the primary aim in 12 of the 16 studies, it is unlikely that voluntary energy restriction contributed to the weight loss. Although there is no evidence that a high intake of simple sugars contributes to passive overconsumption, carbohydrate foods with a low glycaemic index may be more satiating and exert more beneficial effects on insulin resistance and cardiovascular risk factors. Moreover, an increase in protein content up to 25% of total energy may also contribute to reducing total energy intake. In conclusion, a low-fat diet, high in protein and fibre-rich carbohydrates, mainly from different vegetables, fruits and whole grains, is highly satiating for fewer calories than fatty foods. This diet composition provides good sources of vitamins, minerals, trace elements and fibre, and may have the most beneficial effect on blood lipids and blood-pressure levels. A reduction in dietary fat without restriction of total energy intake prevents weight gain in subjects of normal weight and produces a weight loss in overweight subjects, which is highly relevant for public health.     

Lower Fat Intake as a Predictor of Initial and Sustained Weight Loss in Obese Subjects Consuming an Otherwise ad Libitum Diet

Objective To determine what predicts initial and sustained weight loss in subjects consuming a reduced-fat diet ad libitum and the relationship between achieved level of fat intake and weight loss.Design Placebo arm of a randomized, controlled trial of a weight-loss drug (dexfenfluramine) in the context of an ad libitum, reduced-fat, diet.Subjects Thirty-nine subjects (initial mean body mass index±standard deviation=34.9±3.4; body mass index is calculated as kg/m²) from the placebo group who completed the 9-month study.Intervention Dietary assessment and education (month 0) followed by monthly meetings during the single intervention of reducing fat intake (months 1 through 6); one follow-up at 9 months.Main outcome measures Initial weight loss (first 3 months) and sustained weight loss (over 9-month period).Statistics Dietary intake, body size, exercise levels, age, and gender were included in multiple regression linear models of initial and sustained weight loss if they were significant independent predictors.Results Greater initial weight loss was associated with a greater decrease in fat intake and a lower achieved fat intake at 3 months. Greater sustained weight loss was associated with a lower achieved fat intake, a higher baseline waist circumference, and higher moderate-intensity exercise levels (months 3 and 6). Weight loss occurred in all subjects who reported a fat intake of 40 g/day or less.Applications The obese persons most likely to achieve and sustain weight loss on an ad libitum, reduced-fat diet are those who can substantially reduce fat intake, those with high initial levels of abdominal fat, and those who undertake regular moderate-intensity exercise. A target of less than 40 g fat per day might be an appropriate goal to ensure weight loss, but dietary underreporting and the difficulty of sustaining very-low-fat intakes need to be considered. J Am Diet Assoc. 1998;98:35-39.     

Energy and Nutrient Inadequacies in the Diets of Low-Income Women who Breast-Feed

Objective To assess the energy and nutrient intakes of women who are breast-feeding in relation to the Recommended Dietary Allowances (RDAs) for energy and nutrients during lactation.Design Survey using an interviewer-administered questionnaire and a 24-hour dietary recall.Subjects The subjects were 183 women breast-feeding at 3 months postpartum. All were living in low-income communities in Ontario, Canada, that were participating in the longitudinal prevention initiative, Better Beginnings, Better Futures.Statistical analyses Mann-Whitney U test to compare energy and nutrient intakes of women with incomes above and below the Statistics Canada poverty line.Results Median intake of energy (2,148 kcal) was below the RDA of 2,700 kcal. Compared with the RDAs, intakes of calcium (928 vs 1,200 mg), Mate (222 vs 280 μg), iron (13 vs 15 mg), thiamin (1.4 vs 1.6 mg), vitamin A (846 vs 1,300 retinol equivalents), and zinc (10 vs 19 mg) were below recommended values for women who are lactating. Although household income for 70% of the women was below the poverty line, differences in energy and nutrient intakes according to income group were not statistically significant.Applications Lactating women are at high risk of energy and nutrient inadequacies. Programs to increase breast-feeding rates, particularly among low-income communities, must include strategies to ensure adequate diets during lactation. J Am Diet Assoc. 1997;97:1283-1287.     

Varying protein source and quantity do not significantly improve weight loss, fat loss, or satiety in reduced energy diets among midlife adults

We hypothesized that a whey protein diet would result in greater weight loss and improved body composition compared with standard weight loss diets. Weight change, body composition, and renin-angiotensin aldosterone system activity in midlife adults were compared between diet groups. Eighteen subjects enrolled in a 5-month study of 8-week controlled food intake followed by 12-weeks ad libitum intake. Subjects were randomized to 1 of 3 treatment groups: control diet (CD) (55% carbohydrate/15% protein/30% fat), mixed protein (40% carbohydrate/30% protein/30% fat), or whey protein (WP) (40% carbohydrate/15% mixed protein/15% whey protein/30% fat). Measurements included weight, metabolic measures, body composition by dual-energy x-ray absorptiometry, and resting energy expenditure. No statistically significant differences in total weight loss or total fat loss were observed between treatments; however, a trend toward greater total weight loss (P = .08) and total fat loss (P = .09) was observed in the WP group compared with the CD group. Fat loss in the leg and gynoid regions was greater (P < .05) in the WP group than the CD group. No renin-angiotensin aldosterone system-mediated response was observed, but a decrease in systolic blood pressure was significantly greater (P < .05) in the WP group compared with the CD group. In summary, increased whey protein intake did not result in statistically significant differences in weight loss or in total fat loss, but significant differences in regional fat loss and in decreased blood pressure were observed in the WP group.     

Nutrient intakes and body weights of persons consuming high and moderate levels of added sugars.

We classified a nationally representative sample of persons aged 4 years and older as high or moderate consumers of added sugars (ie, sugars added to foods by processors or consumers). Intake of added sugars was determined on the basis of grams consumed per kilogram of body weight (g/kg) and on the basis of percent of dietary energy from added sugars (% kcal). Regardless of the intake measure used, high consumers of added sugars had a significantly lower percentage of dietary energy from fat than did moderate consumers of added sugars. Persons defined by the % kcal measure as high consumers of added sugars took in lower percentages of the Recommended Dietary Allowances (RDAs) for 11 vitamins and minerals; these high consumers had body weights similar to those of their moderate counterparts. Persons defined as high consumers by the g/kg measure consumed greater percentages of the RDAs than did their moderate counterparts; these high consumers more frequently selected foods from categories likely to contain sugar-rich foods but weighed significantly less than did moderate consumers. Thus, different approaches to defining intake of added sugars revealed two patterns of high consumption of added sugars with different levels of nutritional risk. Conditions of overweight were not associated with high intake of added sugars. Educational efforts, therefore, should focus on those consumers who tend to substitute foods rich in added sugars for more nutritionally desirable foods.     

The effects of varying dietary fat on the nutrient intake in male and female runners

OBJECTIVE: The present study examined the effects of varying dietary fat levels on nutrients in female and male endurance runners. METHODS: Three diets (low, medium and high fat) were designed for each subject using their food preferences and three-day food records. Each diet was eaten for 28 to 31 days. The diets were self-selected from seven-day sample menus. Twelve male and 13 female runners between 18 and 55 years of age who averaged 42 miles/week participated in the study. Daily food intakes, activity records and weekly palatability/hunger scales were completed. RESULTS: Dietary fat intakes, as a percent of total energy intake (%E), averaged 17%E, 31%E, and 44%E on the low, medium and high fat diets, respectively. Energy consumption was less than their estimated energy expenditure (EEE) on all diets. On the low fat diet, the female runners were consuming approximately 60% of their EEE. As dietary fat increased, the difference between calorie intake and estimated energy expenditure became less and the subjects were less hungry on the two higher fat diets. For all subjects, as energy intakes increased, so did carbohydrate intake. Therefore, carbohydrate intake was not different on the two lower fat diets. Irrespective of gender, calcium and zinc intakes, which were below 1989 RDAs, increased with increasing fat intakes, between the low and medium fat diets. Zinc intake was also higher on the highest fat diet. Essential fatty acid intakes for females on the low fat diet were less than 2.5%E. Half of the female runners ate less than the RDA of calcium and zinc on the low fat diet and Fe on the medium fat diet. CONCLUSION: This study suggests that endurance runners may not be consuming enough calories on a low fat diet and that increasing dietary fat increased energy consumption. On the low fat diet, essential fatty acids and some minerals (especially zinc) may be too low. A low fat diet could compromise health and performance.