Impact of Dieting Status and Dietary Restraint on Postexercise Energy Intake in Overweight Women

Objective: To investigate the unknown relationship between dieting status and dietary restraint on postexercise energy intake (PE-EI) in overweight sedentary women after a bout of moderate-intensity exercise. Specifically, this was investigated in women who were categorized as dieting with high restraint, nondieting with high restraint, or nondieting with low restraint. Research Methods and Procedures: This study consisted of two experimental conditions, exercise (E) and nonexercise (NE) in a counterbalanced-crossover design on 2 different days. On the E day, the subjects participated in moderate-intensity exercise, walking on a treadmill for 60 minutes at 60% to 70% of their maximum heart rate. PE-EI at lunch and 12 hours after was compared on the E and an NE day. Dietary restraint was determined using the Three-Factor Eating Questionnaire. Results: Participants (n = 36) were 26 ± 7 years of age, sedentary, and had a mean body mass index of 27 ± 3 kg/m². There was a significant interaction (F_(2,33) = 3.32, p = 0.049) of dieting/restraint status and condition (E vs. NE day) on 12-hour EI. The mean difference in 12-hour EI between the E and the NE day was significantly higher (p < 0.01) for the dieting with high restraint than for the nondieting with high restraint. Discussion: The results of this study demonstrate that dieting status, high dietary restraint, and higher levels of disinhibition may influence PE-EI in overweight women after a bout of moderate-intensity physical activity.     

Predictors of Weight Maintenance

PASMAN, WILRIKE J., WIM H.M. SARIS, AND MARGRIET S. WESTERTERP-PLANTENGA. Predictors of weight maintenance. Obes Res. 1999;7:43–50. Objective : To obtain predictors of weight maintenance after a weight-loss intervention. Research Methods and Procedures : An overall analysis of data from two-long intervention studies [n = 67 women; age: 37.9±1.0 years; body weight (BW): 87.0±1.2 kg; body mass index: 32.1±0.5 kg-m^?2; % body fat: 42.4±0.5%]. Subjects were measured before a very low energy diet (month 0), after the very low energy diet of 2 months (month 2) and after a 14-month follow-up phase (at 16 months), in which fiber or a carbohydrate-containing food supplement was supplied. The baseline measurements and the changes in parameters induced by the diet intervention were used to predict the changes in BW in the follow-up phase [ΔBW(2–16)]. Results : Multiple regression analysis revealed that 50% (p<0.71) of the variability in weight regain could be explained by pphysiological and behavioral factors. These were: frequency of previous dieting (r² = 0.27, p<0.05), hunger score (measured with the three-factor eating behavior questionnaire), and change in 24-hour resting metabolic rate (RMR). Frequent dieters showed significantly more weight regain than less frequent dieters (8.8±1.0 kg vs. 5.1 ±0.8 kg, p<0.01). Subjects having parents with obesity regained almost significantly more weight than subjects with lean parents (8.5±0.2 kg vs. 5.1±1.5 kg, respectively; p = 0.06). Discussion : Physiological (ΔRMR-24 hours) and behavioral factors (previous frequency of dieting and hunger score) predicted failure of weight maintenance and, as such, can be used to identify women who are at risk for weight regain.     

Dieting Frequency in Obese Patients With Binge Eating Disorder: Behavioral and Metabolic Correlates

This study examined the clinical significance of self‐reported frequency of time spent dieting in obese patients with binge eating disorder (BED). A total of 207 treatment‐seeking obese BED patients (57 men and 150 women) were dichotomized by dieting frequency and gender and compared on a number of historical, psychological, and metabolic variables. Frequent dieters reported significantly earlier age of onset for binge eating, dieting, and obesity, more episodes of weight cycling, greater weight suppression, and greater eating disorder pathology than infrequent dieters; no differences, however, emerged on current binge eating frequency or psychological distress. Among women but not among men, frequent dieters had consistently lower chances of abnormalities in total cholesterol, high‐density lipoprotein (HDL) cholesterol, and the total/HDL cholesterol ratio while infrequent dieters had greater chances of abnormalities on these variables. Dietary restraint was inversely correlated with abnormalities in triglycerides, HDL cholesterol, and the total/HDL cholesterol ratio but was unrelated to low‐density lipoprotein (LDL) cholesterol. In summary, frequent dieters of both genders had greater lifetime and current eating and weight concerns, and in women, decreased chance of metabolic abnormalities than infrequent dieters. Our findings suggest that frequent dieting attempts, particularly in women, are associated with greater eating disorder pathology but may have a beneficial effect on metabolic functioning and cardiovascular disease risk independent of actual weight status. These findings may have implications for clinical advice provided to obese BED patients.     

Association of Empirically Derived Dietary Patterns with Cardiovascular Risk Factors: A Comparison of PCA and RRR Methods

IntroductionPrincipal component analysis is used to determine dietary behaviors of a population whereas reduced rank regression is used to construct disease-related dietary patterns. This study aimed to compare both types of DP and theirs associations with cardiovascular risk factors (CVRF).ResultsWe found that CVRF-related patterns also reflect eating behaviours of the population. Comparing concordant food groups between both dietary pattern methods, a diet high in fruits, oleaginous and dried fruits, vegetables, olive oil, fats rich in omega 6 and tea and low in fried foods, lean and fatty meat, processed meat, ready meal, soft drink and beer was associated with lower prevalence of CVRF. In the opposite, a pattern characterized by high intakes of fried foods, meat, offal, beer, wine and aperitifs and spirits, and low intakes of cereals, sugar and sweets and soft drinks was associated with higher prevalence of CVRF.ConclusionIn sum, we found that a “Prudent” and “Animal protein and alcohol” patterns were both associated with CVRF and behaviourally meaningful. Moreover, the relationships of those dietary patterns with lifestyle characteristics support the theory that food choices are part of a larger pattern of healthy lifestyle.     

Lean and Weight Stable: Behavioral Predictors and Psychological Correlates

Objective: To examine behavioral characteristics associated with being lean and weight stable during adulthood. Research Methods and Procedures: Participants included 165 white married couples who were part of a larger longitudinal study. Participants’ height and weight were measured on three occasions at 2‐year intervals. Men and women were classified as being lean and weight stable (the target group) if they had a BMI < 25 at baseline and maintained their weight within 5% of baseline at 2nd and 4th year follow‐up. Individuals not fulfilling these criteria were included in the comparison group. Group differences in background characteristics including childhood weight status, BMI at each occasion, dieting history, and mental and physical health history were examined. In addition, multiple measures of dietary intake and physical activity were obtained and used to predict the likelihood of being in the target group. Results: Men (N = 22) and women (N = 36) in the target group had lower mean BMI scores at each occasion, were less overweight during childhood, were less likely to have dieted in the past year, and rated themselves as being more healthy than men and women in the comparison group. No differences were identified in mental health. Relative to the comparison group, women in the target group reported higher levels of physical activity and higher levels of physical activity among their spouses, and men in the target group reported healthier dietary patterns. Discussion: Results from this study suggest that being lean and weight stable in adulthood is linked to childhood weight status in combination with dietary and activity patterns during adulthood.     

Cancer and cardiovascular diseases nutrition knowledge and dietary intake of medical students

The aims of this study were to determine medical students' knowledge regarding the association between dietary factors and the risk of cancer and cardiovascular diseases and to investigate if this knowledge has an impact on their dietary intakes. Three hundred and ninety medical students (males and females) were included in a study and grouped according to their daily fibre and fat intakes. For diet-disease knowledge, questions from the General Nutrition Knowledge Questionnaire for Adults were used and dietary assessment was done with Food Frequency Questionnaire. The obtained results showed that the students' diet-disease knowledge was generally inadequate. Higher level of diet-disease knowledge was among those with high dietary fibre intake, with slightly better scores for dietary factors and risk for cardiovascular diseases than the risk for cancer. Better diet-disease knowledge positively correlated with higher intake of fish (p = 0.027, p = 0.001) and vegetables (p = 0.019, p = 0.001) in high fibre groups of both gender, and in females additionally with fruit intake (p = 0.038, p = 0.007). A higher dietary fibre intake among studied students seems to be a factor that ensures lower obesity rates, lower intake of energy and lower consumption of coffee, sweets and alcoholic drinks. On the basis of the results of this study, it is clear that medical schools should provide in their nutrition programs the opportunity for students to learn about their own dietary and lifestyle behaviours, in order to more knowledgably and convincingly counsel their future patients.     

Race and gender differences in the association of dieting and gains in BMI among young adults

Objective: To assess the relationship between dieting and subsequent weight change and whether the association varies by gender or race/ethnicity. Research Methods and Procedures: Male (n = 4100) and female (n = 4302) participants in the National Longitudinal Study of Adolescent Health who provided information on weight and height at baseline and two follow‐up assessments and were not missing information on weight control strategies or race were studied. Generalized estimating equations were used to assess whether dieting to lose or maintain weight at Wave I or II predicted BMI (kg/m²) change between adolescence and young adulthood (Wave II to III). Analyses were stratified by gender and took sampling weights and clustering into account. Results: At Wave I, the mean age of the participants was 14.9 years. Approximately 29.3% of female participants and 9.8% of male participants reported dieting in Wave I or II. Fewer African Americans than whites (6.2% vs. 10.0% and 25.5% vs. 31.2%, p = 0.007 and p = 0.02, among males and females, respectively) reported dieting. Between Waves II and III, participants gained on average 3.3 kg/m². Independent of BMI gain during adolescence (Waves I to II), female participants who dieted to lose or maintain weight during adolescence made larger gains in BMI during the 5 years between Waves II and III (mean additional gain, 0.39 kg/m²; 95% confidence interval, 0.08 to 0.71) than their nondieting peers. The association was not significant among the male participants. The association was largest among African‐American female participants. Discussion: The results suggest that not only is dieting to lose weight ineffective, it is actually associated with greater weight gain, particularly among female adolescents. Female African‐American dieters made the largest BMI gains.     

High school students' body weight control: differences between athletes and non-athletes

Due to chronic dissatisfaction with body weight in youth, efforts to lose weight often lead to pathological dietary behaviours. Regular and heavy sports activity may contribute to the optimization of body weight, not only by elevating the energy utilization but also by increasing the health consciousness and the tendency to self-monitor. Research generally finds a beneficial role of extracurricular sports activity in body weight control. Therefore, we aim to analyze how regular, heavy sports activity (more precisely, competitive sports) may contribute to body weight control among two groups of youth: athletes and non-athletes. Our study was carried out using 347 adolescents; among them there were 91 athletes and 259 controls. The subjects completed self-administered questionnaires concerning their body weight control and dietary habits. We found that girls were less satisfied with their body weight and reported dieting more frequently with a greater emphasis on healthy dieting than boys. Sport influenced these strong gender differences only regarding healthy dieting, young male athletes laid a larger emphasis on healthy diets than their non-athlete counterparts, therefore their attitude became similar to that of female athletes and non-athletes. We conclude that despite the normal weight in high school students, episodes of dieting that might contribute to eating disorders were quite frequent. This was not influenced by the students' extracurricular sports activity. A greater monitoring of male athletes' and their friend's diet draw attention to the need for developing health education programs specific to boys.     

Dietary behaviors as associated factors for overweight and obesity in a sample of adolescents from Aquitaine, France

This study aimed to identify dietary behaviors that might be considered as associated factors for overweight or obesity among French adolescents. Forty-nine of the 536 middle and high schools in Aquitaine (southwest of France) were invited to take part in the study. For each school, participating adolescents were selected using stratification by grade. A self-report questionnaire, including information about sex, age, dietary behaviors, physical and sedentary activities, and parental socioeconomic status (SES), was filled in by adolescents during class. Overweight and obesity were defined according to the age- and sex-specific body mass index cutoff points of the International Obesity Task Force. Multivariate analysis (logistic regression) was used to identify independent dietary factors associated with overweight including obesity and obesity alone (adjustment on sex, age, parental SES, and weight status and adolescents' sedentary activity). In addition to parental SES and weight status and adolescents' sedentary activity, some dietary behaviors are also independently and significantly associated with a higher prevalence of overweight including obesity: absence (OR 1.43, 0.91–2.23) or rare (OR 1.57, 1.23–2.01) breakfast intake (p?<?0.01) and absence (OR 5.03, 3.19–7.92) or rare (OR 1.90, 1.46–2.47) light afternoon meal intake (p?<?0.001). All variables were also significantly and independently associated with obesity alone. This study shows that socioeconomic factors and individual behaviors are associated with overweight or obesity. These results confirm the importance to carry out multifaceted educational actions among adolescents, by promoting physical activity and healthy food choices in order to prevent overweight and promote healthy lifestyle behaviors.     

Effects of dietary inclusion of Moringa oleifera leaf meal on nutrient digestibility,rumen fermentation,ruminal enzyme activities and growth performance of buffalo calves

This study was conducted to investigate the impact of dietary inclusion of Moringa oleifera leaf meal (MLM) as a substitution for soybean meal on nutrient digestibility, rumen fermentation, rumen enzyme activity, blood metabolites, growth-related hormones, and growth performance of buffalo calves. Thirty buffalo calves eight to nine months of age with an average body weight of approximately 153.7 ± 0.97 kg were randomly distributed through three dietary treatments (ten calves/treatment). MLM inclusion rates were 15% (M15) and 20% (M20), replacing soybean meal by 50 and 75% in the concentrate mixture, respectively. The results indicated that, digestibility of dry matter, organic matter (OM), and crude fiber (CF) increased significantly (p < 0.05) with MLM inclusion, while the digestibility of crude protein (CP) and ether extract (EE) reduced significantly (p < 0.05) with MLM addition. Dietary supplementation with MLM significantly affected (p < 0.001) rumen fermentation by reducing ruminal enzymes, ruminal ammonia-N, total protozoa, and acetate/propionate ratio and increasing acetic, propionic, and butyric acids and total volatile fatty acid concentrations (p < 0.001). Furthermore, dietary inclusion of 15% MLM significantly improved (p < 0.001) final body weight, dry matter intake of feed, daily weight gain, feed conversion efficiency, blood metabolites, and plasma insulin growth factor-I (IGF-I). It can be concluded that MLM is a multi-purpose protein supplement that provides some nutritional and therapeutic advantages when replacing 50% of soybean meal. Dietary supplementation of 15% MLM improved rumen fermentation, growth performance, blood metabolites, plasma IGF-I and mitigated ammonia and methane without any adverse effects in growing buffalo calves.     

Behavioral Strategies of Individuals Who Have Maintained Long-Term Weight Losses

MCGUIRE, MAUREEN T., RENA R. WING, MARY L. KLEM, AND JAMES O. HILL. Behavioral strategies of individuals who have maintained long-term weight losses. Obes Res. Objective: The purpose of the present study was to compare the behaviors of individuals who have achieved long-term weight loss maintenance with those of regainers and weight-stable controls. Research Methods and Procedures: Subjects for the present study were participants in a random-digit dial telephone survey that used a representative sample of the U. S. adult population. Eating, exercise, self-weighing, and dietary restraint characteristics were compared among weight-loss maintainers: individuals who had intentionally lost ≥10% of their weight and maintained it for ≥1 year (n = 69), weight-loss regainers: individuals who intentionally lost ≥10% of their weight but had not maintained it (n = 56), and weight-stable controls: individuals who had never lost ≥10% of their maximum weight and had maintained their current weight (±10 pounds) within the past 5 years (n= 113). Results: Weight-loss maintainers had lost an average of 37 pounds and maintained it for over 7 years. These individuals reported that they currently used more behavioral strategies to control dietary fat intake, have higher levels of physical activity (especially strenuous activity), and greater frequency of self-weighing than either the weight-loss regainers or weight-stable controls. Maintainers and regainers did not differ in reported levels of dietary restraint, but both had higher levels of restraint than the weight-stable controls. Discussion: These results suggest that weight-loss maintainers use more behavioral strategies to control their weight than either regainers or weight-stable controls. It would thus appear that long-term weight maintenance requires ongoing adherence to a low-fat diet and an exercise regimen in addition to continued attention to body weight.     

Social support for healthy behaviors: scale psychometrics and prediction of weight loss among women in a behavioral program

Social support could be a powerful weight-loss treatment moderator or mediator but is rarely assessed. We assessed the psychometric properties, initial levels, and predictive validity of a measure of perceived social support and sabotage from friends and family for healthy eating and physical activity (eight subscales). Overweight/obese women randomized to one of two 6-month, group-based behavioral weight-loss programs (N = 267; mean BMI 32.1 ± 3.5; 66.3% White) completed subscales at baseline, and weight loss was assessed at 6 months. Internal consistency, discriminant validity, and content validity were excellent for support subscales and adequate for sabotage subscales; qualitative responses revealed novel deliberate instances not reflected in current sabotage items. Most women (>75%) "never" or "rarely" experienced support from friends or family. Using nonparametric classification methods, we identified two subscales-support from friends for healthy eating and support from family for physical activity-that predicted three clinically meaningful subgroups who ranged in likelihood of losing ≥5% of initial weight at 6 months. Women who "never" experienced family support were least likely to lose weight (45.7% lost weight) whereas women who experienced both frequent friend and family support were more likely to lose weight (71.6% lost weight). Paradoxically, women who "never" experienced friend support were most likely to lose weight (80.0% lost weight), perhaps because the group-based programs provided support lacking from friendships. Psychometrics for support subscales were excellent; initial support was rare; and the differential roles of friend vs. family support could inform future targeted weight-loss interventions to subgroups at risk.     

Weight Loss Attempts and Attitudes toward Body Size,Eating, and Physical Activity in American Indian Children: Relationship to Weight Status and Gender

Objective: This study examined dieting, weight perceptions, and self‐efficacy to eat healthy foods and engage in physical activity and their relationships to weight status and gender among American Indian elementary schoolchildren. Research Methods and Procedures: Data for this study were collected as part of the baseline examination for the Pathways study. Participants were 1441 second‐ through third‐grade American Indian children in 41 schools representing seven tribes in Arizona, New Mexico, and South Dakota who filled out a questionnaire and had heights and weights taken. Results: Forty‐two percent of the children were overweight or obese. No differences were found between overweight/obese and normal weight children for healthy food intentions or self‐efficacy. Heavier children (especially those with body mass index > 95th percentile) were more likely to have tried to lose weight or were currently trying to lose weight. No gender differences were found. Normal weight children chose a slightly heavier body size as most healthy compared with overweight/obese children. Discussion: The results indicate that children are concerned about their weight and that weight modification efforts are common among overweight American Indian children. School, community, and family‐based programs are needed to help young people adopt lifelong healthful eating and physical activity practices.     

Nutrition and Physical Activity Program to Attenuate Obesity and Promote Physical and Metabolic Fitness in Elementary School Children

Obesity and low levels of physical and metabolic fitness are risk factors for cardiovascular disease and diabetes. The purpose of this investigation was to attenuate obesity and improve physical and metabolic fitness in elementary school children. Schools have the opportunity, mechanisms, and personnel in place to deliver nutrition education, fitness activities, and a school food service that is nutritious and healthy. Cohorts from grades 3 to 5 in two school districts in rural Nebraska (Intervention/Control) participated in a 2-year study of physical activity and modified school lunch program. Data collection for aerobic capacity, body composition, blood chemistry, nutrition knowledge, energy intake, and physical activity was at the beginning and end of each year. Int received enhanced physical activity, grade specific nutrition education, and a lower fat and sodium school lunch program. Con continued with a regular school lunch and team sports activity program. At year 2, Int lunches had significantly less energy (9%), fat (25%), sodium (21%), and more fiber (17%). However, measures of 24-hour energy intake for Int and Con showed significant differences for sodium only. Physical activity in the classroom was 6% greater for Int compared to Con (p < 0.05) but physical activity outside of school was ?16 % less for Int compared to Con (p < 0.05). Body weight and body fat were not different between schools for normal weight or obese children. No differences were found for cholesterol, insulin, and glucose; however, HDL cholesterol was significantly greater and cholesterol/HDL was significantly less for Int compared to Con (p < 0.05). It appears that compensation in both energy intake and physical activity outside of school may be responsible for the lack of differences between Int and Con.     

The Association of Body Weight,Dietary Intake,and Energy Expenditure with Dietary Restraint and Disinhibition

LAWSON, OLGA J, DONALD A WILLIAMSON, CATHERINE M CHAMPAGNE, JAMES P DELANY, ELLEN R BROOKS, PAULA M HOWAT, PATRICIA J WOZNIAK, GEORGE A BRAY AND DONNA H RYAN. The association of body weight, dietary intake, and energy expenditure with dietary restraint and disinhibition. Obes Res. 1995;3:153–161. The hypotheses that dieting and/or overeating are associated with adiposity, eating disturbances, and lowered energy expenditure were tested in this study. A sample of 44 premenopausal women scoring high and low on measures of dietary restraint and disinhibition of dietary control, as measured by the Three Factor Eating Questionnaire, was studied. A 2 × 2 factorial design was employed (High/Low Restraint x High/Low Disinhibition). Dependent variables were: body composition, dietary intake, activity, resting metabolic rate, and thermic effect of food. Unrestrained overeaters (Low Restraint/High Disinhibition group) were very obese. High Dietary Restraint was associated with intent to diet and controlled eating. High scores on the Disinhibition Scale were associated with episodic overeating. Groups did not differ in resting metabolic rate (controlled for fat-free mass). Lower thermic effect of food was found to be associated with the obesity found in High Disinhibition subjects. Thus, Dietary Restraint was not associated with significant adverse effects upon physical or psychological health. High Disinhibition, however, was associated with adiposity and significant disturbances of eating.     

Serotonin,Eating Behavior,and Fat Intake

There is an intimate relationship between nutritional intake (eating) and serotonin activity. Experimental manipulations (mainly neuropharmacological) of serotonin influence the pattern of eating behavior, subjective feelings of appetite motivation, and the response to nutritional challenges. Similarly, nutritional manipulations (food restriction, dieting, or altered nutrient supply) change the sensitivity of the serotonin network. Traditionally, serotonin has been linked to the macronutrient carbohydrate via the intermediary step of plasma amino acid ratios. However, it has also been demonstrated that 5-HT drugs will reduce energy intake and reverse body weight gain in rats exposed to weight increasing high fat diets. 5-HT drugs can also reduce food intake and block weight gain of rats on a high fat cafeteria diet. Some diet selection studies in rats indicate that the most prominent reduction of macronutrient intake is for fat. These data indicate that 5-HT activity can bring about a reduction in fat consumption. In turn, different types of dietary fat can alter brain 5-HT activity. In human studies the methodology of food choice experiments has often precluded the detection of an effect of 5-HT manipulation on fat intake. However, there is evidence that in obese and lean subjects some 5-HT drugs can readily reduce the intake of high fat foods. Data also suggest that 5-HT activation can lead to a selective avoidance of fat in the diet. These effects of 5-HT on the intake of dietary fat may involve a pre-absorptive mechanism and there is evidence that 5-HT is linked to cholecystokinin and enterostatin. These proposals have theoretical and practical implications and suggest possible strategies to intensify or advance fat-induced satiety signals.     

Lifestyle Intervention Favorably Affects Weight Loss and Maintenance Following Obesity Surgery

The present study was designed to evaluate the 3 year effects of a lifestyle intervention on weight loss and maintenance, dietary, and physical activity habits and eating behavior of patients following vertical banded gastroplasty (VBG). Thirty severely obese female volunteers were included in the study and they were randomly assigned to one of two intervention groups: usual care (UC) or lifestyle intervention (LS) group. Patients were followed for 3 years postoperatively. Outcome measures included weight loss, dietary habits, physical activity level (PAL), and eating behavior changes. Weight was significantly lower in the LS group after 12 months (84.4 ± 3.9 kg vs. 98.4 ± 4.4 kg, P < 0.05), 24 months (83.0 ± 3.3 vs. 101.9 ± 5.3 kg, P < 0.05), and 36 months following surgery (84.2 ± 3.3 vs. 102.5 ± 3.5 kg, P < 0.05). Repeated measures ANOVA revealed significant differences between the two groups overall and at specific time points for the PAL and TV viewing. With regard to eating behavior, the LS group scored significantly better in total Dutch Eating Behavior Questionnaire (DEBQ), Restraint Eating and External Eating scales at all postoperative time points. Similarly, significant differences were found between the two groups in dietary intake. These findings outline the importance of lifestyle intervention on weight loss and maintenance following bariatric surgery. The favorable effects of lifestyle intervention may be through adoption of healthier eating behaviors and increased physical activity.     

Adiponectin changes in relation to the macronutrient composition of a weight-loss diet

Adiponectin is an adipose-derived protein with beneficial metabolic effects. Low adiponectin is associated with obesity and related diseases. Significant weight loss increases adiponectin, reducing disease risk. This study compared the effects of two weight-loss diets with different macronutrient compositions on adiponectin. Eighty-one obese women in two cohorts were randomized to a low-fat (LF) or a low-carbohydrate (LC) diet. All subjects underwent equivalent weight-loss intervention, with weight and other measures assessed at baseline and after 6 (cohort I) or 4 (cohort II) months. Body fat was measured by dual energy X-ray absorptiometry. Adiponectin was measured by radioimmunoassay. Diet intake was assessed using 24-h recalls and 3-day diet records. Data were analyzed via t-tests and repeated-measures factorial ANOVA using time, diet, and replicate (cohort I vs. cohort II) as factors. Age, weight, body fat, BMI, adiponectin, and diet were similar at baseline. Following intervention, macronutrient composition of the diet was vastly different between the groups, reflecting the assigned diet. Both groups lost weight and body fat (P < 0.001), with effect in LC dieters greater than LF dieters (-9.1 kg vs. -4.97 kg weight, P < 0.05 and -5.45 kg vs. -2.62 kg fat, P < 0.001). Adiponectin increased in the LC (+1.92 mcg/ml, P < 0.01), but not the LF (+0.86 mcg/ml, P = 0.81), group. There was no correlation between weight loss and increase in adiponectin. These results confirm that diet-induced loss of weight and body fat is associated with increased adiponectin concentrations. This effect is evident with weight loss of 10% or more, and may be greater with LC diets.     

Weight-Loss Strategies Used by the General Population: How Are They Perceived?

Background

The rising prevalence of obesity and the social pressure for thinness increase the prevalence of dieting. However, little is known about the overall perception of dieting strategies actually used by the general population.

Objectives

Our main objective was to investigate perceptions of weight-loss practices in an observational study in order to identify the most favourable strategy.

Design

Adults from the ongoing Nutrinet-Santé cohort study who had reported engaging in dieting in the three previous years were included in the study. For each diet, detailed information was collected on types of diets, circumstances and perception of the diet, and outcomes. Perceptions were compared across diets using sex-specific mixed effects models.

Result

Among the 48 435 subjects who had completed the respective questionnaire, 12 673 (26.7%, 87.8% of women) had followed at least one weight-loss diet in the previous three years. Diet plans prescribed by health professionals and diets conforming to official dietary recommendations were the most favourably perceived among all assessed weight-loss strategies. Alternatively, commercial diet plans and self-imposed dietary restrictions were more negatively perceived (Odds ratios (OR) for adherence difficulty 1.30 (95% confidence interval (0.99;1.7)) in men and OR 1.92 (1.76;2.10) in women compared to official nutritional guidelines; OR 1.06 (0.82;1.38) in men and OR 1.39 (1.26;1.54) in women respectively) compared to official nutritional guidelines.

Conclusion

Official dietary recommendations could be useful tools for maintaining a dietary balance while following a weight-loss diet.