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.     

Body composition of patients with Alzheimer's disease

Low body weight is frequently reported in patients with Alzheimer's disease. We sought to discover why by comparing the body composition of 28 cognitively normal elders and 23 institutionalized individuals with Alzheimer's disease. Body mass index was calculated from standing height and weight. Percentages of lean body mass, body fat, and body water were derived from bioimpedance measurements of resistance and reactance. Skinfold thickness was measured at seven body sites to estimate regional fat distribution. Variables were analyzed by analysis of variance with subjects grouped by cognitive status within gender. Activity level and age were not significant covariates. Both women and men with Alzheimer's disease weighed less than control subjects. Differences in body composition were more pronounced in women with Alzheimer's disease, who had lower body mass index (22.0 ± 3.0 vs 26.1 ± 5.1), higher percentage of lean body mass (73.8 ± 5.1 vs 66.9 ± 6.5), lower percentage of body fat (26.1 ± 5.1 vs 33.1 ± 6.5), and higher percentage of body water (55.8 ± 5.0 vs 49.3 ± 6.5) compared with control women. Except for lower body weight, the body composition of men with Alzheimer's disease was not significantly different from that of control men. Patients of both sexes with Alzheimer's disease had less truncal body fat compared with controls, which gave them a youthful body habitus. These differences were not accounted for by age, diet, or activity. Our findings indicate that patients with Alzheimer's disease have lower body weight and may require higher energy intake than cognitively normal elders.     

Persons Successful at Long-term Weight Loss and Maintenance Continue to Consume a Low-energy, Low-fat Diet

Objectives To describe the dietary intakes of persons who successfully maintained weight loss and to determine if differences exist between those who lost weight on their own vs those who received assistance with weight loss (eg, participated in a commercial or self-help program or were seen individually by a dietitian). Intakes of selected nutrients were also compared with data from the third National Health and Nutrition Examination Survey (NHANES III) and the 1989 Recommended Dietary Allowances (RDAs).Subjects Subjects were 355 women and 83 men, aged 18 years or older, primarily white, who had maintained a weight loss of at least 13.6 kg for at least 1 year, and were the initial enrollees in the ongoing National Weight Control Registry. On average, the participants had lost 30 kg and maintained the weight loss for 5.1 years.Methods A cross-sectional study in which subjects in the registry completed demographic and weight history questionnaires as well as the Health Habits and History Questionnaire developed by Block et al. Subjects’ dietary intake data were compared with that of similarly aged men and women in the NHANES III cohort and to the RDAs. Adequacy of the diet was assessed by comparing the intake of selected nutrients (iron; calcium; and vitamins C, A, and E) in subjects who lost weight on their own or with assistance.Results Successful maintainers of weight loss reported continued consumption of a low-energy and low-fat diet. Women in the registry reported eating an average of 1,306 kcal/day (24.3% of energy from fat); men reported consuming 1,685 kcal (23.5% of energy from fat). Subjects in the registry reported consuming less energy and a lower percentage of energy from fat than NHANES III subjects did. Subjects who lost weight on their own did not differ from those who lost weight with assistance in regards to energy intake, percent of energy from fat, or intake of selected nutrients (iron; calcium; and vitamins C, A, and E). In addition, subjects who lost weight on their own and those who lost weight with assistance met the RDAs for calcium and vitamins C, A, and E for persons aged 25 years or older.Applications Because continued consumption of a low-fat, low-energy diet may be necessary for long-term weight control, persons who have successfully lost weight should be encouraged to maintain such a diet. J Am Diet Assoc. 1998;98:408–413.     

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.     

Dairy Calcium is Related to Changes in Body Composition during a Two-Year Exercise Intervention in Young Women

Objective: Relationships between micronutrients and dairy product intake and changes in body weight and composition over two years were investigated.

Design: Two year prospective non-concurrent analysis of the effect of calcium intake on changes in body composition during a two year exercise intervention.

Subjects: 54 normal weight young women, 18 to 31 years of age.

Measures of Outcome: Mean intakes of nutrients of interest were determined from three-day diet records completed at baseline and every six months for two years. The change in total body weight and body composition (assessed by dual x-ray absorptiometry) from baseline to two years was also determined.

Results: Total calcium/kilocalories and vitamin A together predicted (negatively and positively, respectively) changes in body weight (R² = 0.19) and body fat (R² = 0.27). Further, there was an interaction of calcium and energy intake in predicting changes in body weight, such that, only at lower energy intakes, calcium intake (not adjusted for energy) predicted changes in body weight.

Conclusions: Regardless of exercise group assignment, calcium adjusted for energy intake had a negative relationship and vitamin A intake a positive relationship with two year changes in total body weight and body fat in young women aged 18 to 31 years. Thus, subjects with high calcium intake, corrected by total energy intake, and lower vitamin A intake gained less weight and body fat over two years in this randomized exercise intervention trial.     

Effect of β3-adrenergic receptor gene polymorphism on body weight change in middle-aged, overweight women

Objectives To examine the effects of β₃-adrenergic receptor gene polymorphism on body weight change during a weight reduction program for middle-aged, overweight women with careful consideration of their energy intake and expenditure. Methods Design: Intervention study of weight reduction for 12 weeks in a community setting. Subjects: Eighty overweight middle-aged women who completed the individualized lifestyle modification program. Measurements: β₃-adrenergic receptor gene polymorphism was identified by polymerase chain reaction and consecutive restriction fragment-length polymorphism analysis. Anthropometrical parameters, lifestyle factors, blood lipid and glucose levels, physical activity level and energy intake were measured before and at the end of the program. Results The numbers of subjects with the Trp64Trp, Trp64Arg, and Arg64Arg genotypes were 45, 30 and 5, respectively. Baseline characteristics among subjects with the 64Arg allele had significantly smaller decrease in body weight and energy intake than those without the 64Arg allele. The change of other clinical characteristics did not differ between the two groups. After adjusting for the %change of energy intake, the %change of body weight did not differ between the two groups. Conclusion The 64Arg allele of the β₃-AR gene is not likely to be the factor determining the difficulty in losing body weight in Japanese middle-aged, overweight women. Lifestyle factors, such as the decrease in energy intake, might mask the effect of the 64Arg allele on body weight loss. Specific considerations for the management of energy intake would be needed to promote body weight loss for those with the 64Arg allele.     

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.     

Energy expenditure in Alzheimer's disease

Alzheimer's disease type dementia is a growing health problem and is one of the leading causes of death among elderly people. Unexplained weight loss and cachexia is a frequent clinical finding in patients with Alzheimer's disease. It has been postulated that Alzheimer's disease may by characterized by dysfunction in body weight regulation. This brief review examines energy intake, energy expenditure and body composition in Alzheimer's disease. We consider whether inappropriately high levels of energy expenditure may contribute to unexplained weight loss and decline in nutritional status. Specifically, we will consider studies that have examined body composition, daily energy expenditure and its components. The application of doubly labeled water and indirect calorimetry to problems of "wasting" has increased our knowledge regarding energy expenditure and physical activity levels in Alzheimer's patients. Although the number of studies are limited, results do not support the notion that a "hypermetabolic" state contributes to unexplained weight loss in Alzheimer's disease, even in cachectic patients. Clinical strategies aimed at developing feeding strategies to maintain adequate caloric intake and the restoration of energy balance should be a future area of investigation in Alzheimer's research.     

Dietary Intake and Counseling, Weight Maintenance, and the Course of HIV Infection

Objective To define relationships among dietary intake and counseling, weight maintenance, and the clinical course of patients infected with the human immunodeficiency virus(HIV).Design A prospective cohort study in an HIV clinic in a county hospital.Subjects HIV-infected patients (68 with and 40 without acquired immunodeficiency syndrome [AIDS]) who had a good performance status and no chronic diarrhea were assessed at entry to the study and after 6 months. The following assessments were made: energy and nutrient intake based on 7-day food records, anthropometric measurements, immunologic function as lymphocyte T-cell subpopulations (ratio of CD4 to CD8), and serum cholesterol level. Patients were monitored to determine clinical outcome.Intervention All patients received standardized dietary counseling designed to address identified intake deficiencies and maintain body weight.Main outcome measures Changes in energy and nutrient intake, body weight, and clinical outcome (ie, time to AIDS-defining illness and overall survival time).Statistical analyses performed Group differences (HIV group vs AIDS group) were sought using χ² analyses and Student's t test. A multivariate regression model was used to determined the best predictors of clinical outcome.Results At baseline, total energy intake (based on 30 kcal/kg usual body weight) was adequate in both HIV and AIDS patients (101±4% and 103±5% [mean±standard deviation] of need, respectively). Despite dietary counseling and continued maintenance of energy intake, body weight, serum cholesterol level, and CD4 level progressively decreased. Consequently, saturated fat intake was found to be inversely related (P<.01) to serum cholesterol level. Clinical outcome (after 3.5 years) was associated with baseline ratio of CD4 to CD8 (P<.0001), weight (P<.01), and serum cholesterol level (P<.001). Multivariate analysis related ratio of CD4 to CD8 (P<.001) and weight maintenance (P<.001) to favorable outcome in the final model.Applications Weight loss in patients with HIV infection is independently prognostic of clinical outcome, and development of hypocholesterolemia is not favorable for clinical outcome. Because weight loss progresses despite conventional dietary counseling to identify energy need, interventions earlier in the disease course should be considered along with increased target levels for energy intake. J Am Diet Assoc. 1995; 95:428–432, 435.     

Women and Men with Hypercholesterolemia Respond Similarly to an American Heart Association Step 1 Diet

Objective To compare serum lipid level responses of women and men with hypercholesterolemia to an American Heart Association (AHA) step 1 diet.Design Sixty-three women and 99 men with varying degrees of hypercholesterolemia were instructed on an AHA step 1 diet. Subjects were followed up on a biweekly basis with individual visits and group classes for 8 weeks.Setting Outpatient clinic facility of the Metabolic Research Group, University of Kentucky, Lexington.Subjects/samples Through community cholesterol screenings, we recruited 76 women and 108 men aged 30 to 70 years who were within 80% to 130% of their ideal body weight. Serum cholesterol levels were between 5.17 mmol/L and 8.99 mmol/L and serum triglyceride levels when subjects were fasting were less than 5.08 mmol/L. Sixty-three women and 99 men completed the study.Intervention Subjects followed an AHA step 1 diet (30% of energy from fat, 50 to 60% of energy from carbohydrate, 10 to 20% of energy from protein, and less than 300 mg cholesterol per day) for 8 weeks.Main outcome measures Serum lipid levels, nutrient intake, and body weight.Statistical analyses performed Subjects were divided into three groups according to initial serum cholesterol levels (mild=5.17 to 6.17 mmol/L; MODERATE=6.20 to 6.95 mmol/L; SEVERE = 6.98 mmol/L). Within-individual changes in nutrient intakes, body weights, and serum lipid levels were analyzed using dependent t tests. Between-group comparisons were made using analysis of variance (ANOVA). When significant differences were found using ANOVA, differences between groups were evaluated with the Tukey test.Results All subjects tolerated the diet well and average dietary adherence was good, as assessed by a food frequency questionnaire and analysis of 3-day diet records. Serum total cholesterol levels decreased 9.2% overall for women (P<.001) and 7.2% for men (P<.001); serum low-density lipoprotein cholesterol levels decreased 9.2% for women and 9.8% for men; and serum high-density lipoprotein cholesterol levels decreased 3.6% for women and 2.8% for men. Mean serum triglyceride levels decreased significantly for women but not for men. No significant differences were found in the responses of women and men in the corresponding groups. Women and men with higher initial serum cholesterol values showed significantly greater hypocholesterolemic responses to diet than those with lower initial serum cholesterol values.Applications/conclusions The findings of this study confirm the beneficial role of dietary intervention for reducing atherogenic serum lipid levels in women and men. J Am Diet Assoc. 1995; 95:436–441.     

Long-chain polyunsaturated fatty acid supplementation had no effect on body weight but reduced energy intake in overweight and obese women

Longer-chain polyunsaturated fatty acids may have greater appetite-suppressing effects than shorter-chain, monosaturated, and saturated fatty acids. Because fish oils are predominantly composed of n-3 long-chain polyunsaturated fatty acid and may assist in the treatment of obesity comorbidities, their effect on body weight and body mass index is of interest. We hypothesized that daily supplementation with docosahexaenoic acid (DHA)–rich oil would reduce energy intake and body weight in overweight and obese women compared with supplementation with oleic acid (OA) rich oil. A double-blinded, randomized, parallel intervention was conducted. Body mass index (in kilograms per meter squared), body weight (in kilograms), body fat (in percent), and lean tissue (in kilograms) were measured at baseline and 12 weeks after intervention with DHA or OA. Diet diaries were also completed at these time points for estimation of energy and macronutrient intake. Subjects reported significantly lower energy (P = .020), carbohydrate (g) (P = .037), and fat (g) (P = .045) intake after DHA compared with OA. Body mass or composition was not affected by treatment, although a fall in body weight in the DHA group approached statistical significance (P = .089). Daily ingestion of DHA over a 12-week period may reduce energy intake in overweight and obese females, but longer-term and adequately powered studies using subjects of both sexes are needed. Other factors that should be considered include the following: the choice of control, the body mass index category of subjects, and ways of improving the compliancy and accuracy of dietary assessment.     

Body Composition, Dietary Intake, and Energy Expenditure in Nonobese, Prepubertal Children of Obese and Nonobese Biological Mothers

Objective To determine differences in dietary intake, resting energy expenditure, activity level, fat-free mass, and percentage body and abdominal fat in nonobese children of obese mothers compared with nonobese children of nonobese mothers.Design Cross-sectional comparison study. Children's food diaries were analyzed to determine average energy and nutrient content. Resting energy expenditure of children was measured by means of indirect calorimetry. Children's activity levels were estimated through questionnaires administered during interviews. Dual-energy x-ray absorptiometry was used to estimate body composition of children.Subjects Mothers of subjects responded to advertisements and were recruited as nonobese (body mass INDEX=20 to 25) or obese (body mass index ≥30). Offspring included in the study were prepubertal and nonobese (10th to 90th percentile of weight for height by gender). Twelve pairs of children could be matched for weight, gender, and age.Statistical analysis performed Wilcoxon signed rank tests were used to determine differences between the 2 groups of children.Results Percentage abdominal fat was greater (median DIFFERENCE=3.15, P=.001) and fat-free mass was lower (median DIFFERENCE=1.19, P=.04) in children of obese mothers compared with children of nonobese mothers. No statistically significant differences between the 2 groups of children were found for dietary intake, resting energy expenditure, activity level, or percentage body fat.Applications/conclusions The significantly higher percentage of abdominal fat and lower fat-free mass in children of obese mothers may contribute to obesity onset. Use of dual-energy x-ray absorptiometry as a screening tool for nonobese, prepubertal children with an obese parent will help to identify those at risk. Education and lifestyle changes can then be implemented to help prevent the onset of obesity. J Am Diet Assoc. 1999;99:58-65.     

Decreased Fat and Nitrogen Losses in Patients with AIDS Receiving Medium-Chain-Triglyceride-Enriched Formula Vs Those Receiving Long-Chain-Triglyceride-Containing Formula

Objective The purpose of this study was to compare two enteral formulas, differing only in fat source, for product acceptance, tolerance, and effect on fat malabsorption and nutritional status in subjects with acquired immune deficiency syndrome (AIDS).Design The double-blind, randomized 15-day trial was divided into a 3-day period in which solid food was consumed followed by a 12-day experimental period in which liquid formulas were consumed.Setting/subjects Twenty-three men and one woman with AIDS and fat malabsorption completed the study. The study was conducted in the General Clinical Research Center, University of Alabama Hospital, University of Alabama at Birmingham. Laboratory assays were performed in the Department of Nutrition Sciences.Interventions After 3 days of consuming a controlled, solid food diet containing 100 g fat per day from mixed sources to document fat malabsorption, subjects were randomly assigned to one of two groups. Each group received a liquid formula containing 35% of energy as fat for 12 days. One group received a formula containing 85% medium-chain triglycerides (MCTs) and the control group received a formula containing 100% long-chain triglycerides.Main outcome measures Determinations included stool number, consistency, weight, and fat and nitrogen content; urine nitrogen and creatinine levels; and body weight.Statistical analysis performed Subject demographic and other baseline characteristics were compared using two-sample t tests; stool and urine assessments were compared between groups at the initial experimental period using two-sample t tests; changes from initial to final experimental periods were assessed by means of analysis of covariance; changes in pooled intake, body weight, and the number and consistency of bowel movements were also assessed using analysis of covariance. All statistical tests were two-tailed and considered significant at P<.05.Results Within-group comparisons indicated that subjects fed the MCT formula showed significantly decreased stool fat and stool nitrogen content (P=.01 and P=.03, respectively) and increased fat absorption (P=.03), whereas those fed the control formula did not. Differences in stool fat between the groups were not statistically significant. However, the difference in fat absorption from the initial to final formula period was significant (P=.04). Subjects consuming the MCT formula also tended to have a decreased number of bowel movements and abdominal symptoms, whereas subjects fed the control formula showed no improvement. All subjects maintained their body weights.Applications There may be advantages to using an MCT-based formula in the treatment of AIDS-associated malabsorption.     

Behavioral and body size correlates of energy intake underreporting by obese and normal-weight women

Objective To examine behavioral and body size influences on the underreporting of energy intake by obese and normal-weight women.Design Seven-day estimated food records were kept by subjects before they participated in a 49-day residential study. Self-reported energy intake was compared with energy intake required to maintain a stable body weight during the residential study (reference standard). Energy intake bias and its relationship to various body size and behavioral measures were examined.Subjects Twenty-two, healthy, normal-weight (mean body mass index [BMI]=21.3) and obese (mean BMI=34.2) women aged 22 to 42 years were studied.Statistical analyses Analysis of variance, paired t test, simple linear regression, and Pearson correlation analyses were conducted.Results Mean energy intake from self-reported food records was underreported by normal-weight (−9.7%) and obese (−19.4%) women. BMI correlated inversely with the energy intake difference for normal-weight women (r=−.67, P=.02), whereas the Beck Depression Inventory correlated positively with the energy intake difference for obese women (r=.73, P<.01).Conclusion/applications Results suggest that body size and behavioral traits play a role in the ability of women to accurately self-report energy intake. BMI appears to be predictive of underreporting of energy intake by normal-weight women, whereas emotional factors related to depression appear to be more determinant of underreporting for obese women. Understanding causative factors of the underreporting phenomenon will help practicing dietitians to devise appropriate and realistic diet intervention plans that clients can follow to achieve meaningful change. J Am Diet Assoc. 1999;99:300-306.     

Alcohol energy intake and habitual physical activity in older adults

Alcohol forms a significant component of many diets and it supplements rather than displaces daily energy intake. Surprisingly, alcohol intake does not systematically increase body weight. The present study assessed whether a higher level of habitual physical activity in the daily environment is associated with a higher alcohol intake. Alcohol intake as part of total food intake was measured with a 7 d dietary record while at the same time physical activity was monitored with a tri-axial accelerometer for movement registration. Subjects were twenty women and twenty-four men, aged 61+/-5 years, of BMI 27.1+/-4.6 kg/m(2). Between subjects, there was a positive association between the level of habitual physical activity and alcohol intake (r 0.41; P<0.01). The subjects with higher alcohol intake had a higher activity level. On days with and days without alcohol consumption there was no difference in physical activity within subjects. In conclusion, it was shown that subjects with higher alcohol consumption are habitually more active. This may explain the lack of increasing body weight through additional energy intake from alcohol.     

Using Cluster Analysis to Examine Dietary Patterns: Nutrient Intakes, Gender, and Weight Status Differ Across Food Pattern Clusters

Objective This study explored the usefulness of cluster analysis in identifying food choice patterns of three groups of adults in relation to their energy intake.Design Food frequency data were converted to percentage of total energy from 38 food groups and entered into a cluster analysis procedure. Subjects in the emerging food group patterns were compared in terms of weight status, demographics, and the nutrition composition of their usual diet.Setting Data were collected as part of three studies in two US metropolitan areas using identical protocols. Participants were university employees (103 women and 99 men) who volunteered for a reliability study of health behavior questionnaires and moderately obese volunteers (223 women and 101 men) to two weight-loss studies who were recruited by newspaper advertisements.Statistical analysis performed Subjects were clustered according to food energy sources using the FASTCLUS procedure in the Statistical Analysis System. One-way analysis of variance and χ² analysis were then performed to compare the weight status, nutrient intakes, and demographics of the food patterns.Results Six food pattern clusters were identified. Subjects in the two clusters associated with high consumption of pastry and meat had significantly higher fat intakes (P=.0001). Subjects in two other clusters, those associated with high intake of skim milk and a broad distribution of energy sources had significantly higher micronutrient levels (P=.0001). Body mass index and the distribution of gender were also significantly different across clusters.Conclusions The success of cluster analysis in identifying dietary exposure categories with unique demographic and nutritional correlates suggests that the approach may be useful in epidemiologic studies that examine conditions such as obesity, and in the design of nutrition interventions. J Am Diet Assoc. 1997:97:272–279.     

The Gustaf Study: Repeated, Telephone-Administered 24-hour Dietary Recalls of Obese and Normal-Weight Men — Energy and Macronutrient Intake and Distribution Over the Days of The Week

Objective A dietary survey of obese and control men was conducted through 24-hour dietary recalls administered by telephone at 12 times selected randomly over a period of 3 months. Energy and macronutrient intake and distribution were studied for all days of the week.Subjects Eighty-six obese men, 20 to 60 years old, body mass index (BMI)= 37.7±4.4 (mean±standard deviation) from the waiting list of the outpatient clinic and 61 normal-weight (BMI= 23.0±1.9), age-matched men selected randomly from the Stockholm County Census Bureau.Main outcome measures Energy and macronutrient intake, intakes by energy tertiles, and distribution over the days of the week.Statistical analyses Nonparametric tests were used because of skewed distribution of most food data.Results A median daily energy intake of 2,700 kcal was found in both groups. The obese men reported a higher protein (P<.001) and a lower alcohol (P<.001) intake than the control subjects. Both groups reported a maximum intake of energy and macronutrients on Saturdays. When separated into tertiles according to reported energy intake, the obese men in tertile 3 reported a higher intake from fat (% energy, P<.001) and a lower intake from protein (P<.01) compared with men in tertile 1. Normal-weight men in tertile 3 reported a higher intake from fat (% energy, P<.01) compared with men in tertile 1.Conclusions When reported energy intake was compared with calculated total daily energy expenditure, there was a greater discrepancy in the obese group than in the control group. The normal-weight men may have had a special interest in food and health, and this group may not reflect the population at large. J Am Diet Assoc. 1996; 96:686–692.     

Dietary Change and Obesity Associated with Glucose Intolerance in Alaska Natives

Objective To investigate frequency of food intake, body weight, and glucose intolerance in Alaska Natives.Design Height, weight, and random blood glucose levels were measured and a frequency-of-food-intake questionnaire was obtained. This questionnaire classified persons as consumers of indigenous foods or nonindigenous foods within three food groups. Those with a random blood glucose measurement ≥6.72 mmol/L received an oral glucose tolerance test.Setting Community screening in 15 villages in Alaska.Subjects Nutrition screenings were done for 1,124 Alaska Native residents aged 20 years or older. An oral glucose tolerance test was done for 202 subjects.Outcomes measured Subjects were classified as consumers of indigenous or nonindigenous foods within three food groups. A diagnosis of non–insulin-dependent diabetes mellitus (NIDDM) was made on the basis of World Health Organization criteria. A determination of overweight was made on the basis of National Center for Health Statistics criteria.Statistical analysis A χ² test with Yates correction, t test, and linear regression, with two-sided P values.Results Athabascan Indians had twice the rate of NIDDM as Yup’ik Eskimos with significantly higher frequency of non-indigenous food intake, plus lower frequency of indigenous carbohydrate and fat intake. Subjects ≤30 years old consumed significantly more nonindigenous protein and fat and low-nutrient-density carbohydrates than those ≥60 years old. Persons who had glucose intolerance reported significantly greater consumption of nonindigenous protein and less seal oil. Incidence of overweight was significantly higher than was found 25 years ago. Participants with glucose intolerance were significantly more overweight than others.Conclusion A pattern of increased frequency of non-indigenous protein, low-nutrient-density carbohydrate, and fat intake with less indigenous carbohydrate and fat consumption was found in subjects ≤30 years old and in association with the higher rate of NIDDM found in the Athabascan Indians. Persons with glucose intolerance were significantly more overweight than others.Applications Although the nutritional value of indigenous foods for reducing disease risk should be promoted, nutrition education, especially among young adults, should also include building skills to select and prepare nonindigenous foods to attain a healthful diet. Although snacking is a concern, dietary fat was the most significant factor in obesity and NIDDM. J Am Diet Assoc. 1995; 95:676-682.     

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.