Recent weight changes and weight cycling as predictors of subsequent two year weight change in a middle-aged cohort

Annual variation in Internet keyword searches: Linking dieting interest to obesity and negative health outcomes

This study investigated the annual variation in Internet searches regarding dieting. Time-series analysis was first used to examine the annual trends of Google keyword searches during the past 7 years for topics related to dieting within the United States. The results indicated that keyword searches for dieting fit a consistent 12-month linear model, peaking in January (following New Year's Eve) and then linearly decreasing until surging again the following January. Additional state-level analyses revealed that the size of the December-January dieting-related keyword surge was predictive of both obesity and mortality rates due to diabetes, heart disease, and stroke.

Supported exercise improves controlled eating and weight through its effects on psychosocial factors: extending a systematic research program toward treatment development

BACKGROUND

Behavioral weight-loss treatments have been overwhelmingly unsuccessful. Many inadequately address both behavioral theory and extant research--especially in regard to the lack of viability of simply educating individuals on improved eating and exercise behaviors.

OBJECTIVE

The aim was to synthesize research on associations of changes in exercise behaviors, psychosocial factors, eating behaviors, and weight; and then conduct further direct testing to inform the development of an improved treatment approach.

METHODS

A systematic program of health behavior-change research based on social cognitive theory, and extensions of that theory applied to exercise and weight loss, was first reviewed. Then, to extend this research toward treatment development and application, a field-based study of obese adults was conducted. Treatments incorporated a consistent component of cognitive-behaviorally supported exercise during 26 weeks that was paired with either standard nutrition education (n = 183) or cognitive-behavioral methods for controlled eating that emphasized self-regulatory methods such as goal setting and caloric tracking, cognitive restructuring, and eating cue awareness (n = 247).

RESULTS

Both treatment conditions were associated with improved self-efficacy, self-regulation, mood, exercise, fruit and vegetable consumption, weight, and waist circumference; with improvements in self-regulation for eating, fruit and vegetable consumption, weight, and waist circumference significantly greater in the cognitive-behavioral nutrition condition. Changes in exercise- and eating-related self-efficacy and self-regulation were associated with changes in exercise and eating (R(2) = 0.40 and 0.17, respectively), with mood change increasing the explanatory power to R(2) = 0.43 and 0.20. Improved self-efficacy and self-regulation for exercise carried over to self-efficacy and self-regulation for controlled eating (β= 0.53 and 0.68, respectively).

CONCLUSIONS

Development and longitudinal testing of a new and different approach to behavioral treatment for sustained weight loss that emphasizes exercise program-induced psychosocial changes preceding the facilitation of improved eating and weight loss should be guided by our present research.

How dieting makes some fatter: from a perspective of human body composition autoregulation

Dieting makes you fat - the title of a book published in 1983 - embodies the notion that dieting to control body weight predisposes the individual to acquire even more body fat. While this notion is controversial, its debate underscores the large gap that exists in our understanding of basic physiological laws that govern the regulation of human body composition. A striking example is the key role attributed to adipokines as feedback signals between adipose tissue depletion and compensatory increases in food intake. Yet, the relative importance of fat depletion per se as a determinant of post-dieting hyperphagia is unknown. On the other hand, the question of whether the depletion of lean tissues can provide feedback signals on the hunger-appetite drive is rarely invoked, despite evidence that food intake during growth is dominated by the impetus for lean tissue deposition, amidst proposals for the existence of protein-static mechanisms for the regulation of growth and maintenance of lean body mass. In fact, a feedback loop between fat depletion and food intake cannot explain why human subjects recovering from starvation continue to overeat well after body fat has been restored to pre-starvation values, thereby contributing to 'fat overshooting'. In addressing the plausibility and mechanistic basis by which dieting may predispose to increased fatness, this paper integrates the results derived from re-analysis of classic longitudinal studies of human starvation and refeeding. These suggest that feedback signals from both fat and lean tissues contribute to recovering body weight through effects on energy intake and thermogenesis, and that a faster rate of fat recovery relative to lean tissue recovery is a central outcome of body composition autoregulation that drives fat overshooting. A main implication of these findings is that the risk of becoming fatter in response to dieting is greater in lean than in obese individuals.

Low-income Supplemental Nutrition Assistance Program participation is related to adiposity and metabolic risk factors

BACKGROUND

The Supplemental Nutrition Assistance Program (SNAP) is the largest federal nutrition assistance program. In recent years, SNAP participation rates increased during times of economic hardship.

OBJECTIVE

We examined whether household SNAP participation was associated with adiposity and metabolic risk factors in a representative sample of low-income US adults.

DESIGN

A cross-sectional analysis was performed with the use of data from the 2003-2006 National Health and Nutrition Examination Surveys. The study population was restricted to nonelderly adults whose household incomes fell to or <130% of the federal poverty level. Multinomial logistic and Poisson regression models were fit to examine the associations between SNAP participation and BMI, waist circumference, and metabolic risk factors among 2250 low-income adults.

RESULTS

In the previous 12 mo, 32.8% of adults received household SNAP benefits. SNAP participation was positively associated with obesity [prevalence ratio (PR): 1.58; 95% CI: 1.08, 2.31], waist circumference in men (PR for top compared with bottom quartile: 2.04; 95% CI: 1.15, 3.62; P = 0.02), and waist circumference in women (PR: 2.95; 95% CI: 1.51, 5.77; P = 0.003; P-interaction with sex = 0.11), independent of sociodemographic characteristics. SNAP participation was also related to elevated triglycerides (PR: 1.71; 95% CI: 1.33, 2.20), lower HDL cholesterol (PR: 1.23; 95% CI: 1.08, 1.41), elevated fasting glucose (≥110 mg/dL; PR: 1.63; 95% CI: 1.05, 2.52), and metabolic syndrome (PR: 1.49; 95% CI: 1.13, 1.95). Associations with triglycerides and HDL cholesterol persisted after adjustment for BMI.

CONCLUSION

Household SNAP participation was positively associated with BMI, waist circumference, and metabolic risk factors among low-income adults. These associations may be mediated by dietary intake and warrant further investigation.

Correlates of weight instability across the lifespan in a population-based sample

OBJECTIVE

Research from overweight/obese clinical samples links weight instability to poor health. This study investigated whether negative health outcomes were associated with weight instability in a population-based sample.

METHOD

One thousand five hundred ten women and 1,111 men from the Mid-Atlantic Twin Registry completed questionnaires assessing demographics, body size in childhood, adolescence, and adulthood, health satisfaction, and disordered eating. Noneating disorder psychiatric diagnoses were assessed via clinical interviews.

RESULTS

Weight instability was related to lower health satisfaction and self-esteem, and higher body dissatisfaction, dieting, and binge eating for both sexes. Weight unstable women were more likely to meet criteria for lifetime major depressive disorder, generalized anxiety disorder, and eating disorders. Weight stable women were more likely to abuse alcohol; however, two of these associations [e.g. weight instability and generalized anxiety disorder (GAD) and weight stability and alcohol abuse] became nonsignificant once lifetime binge eating was accounted for, indicating that these forms of psychopathology are more strongly related to binge eating than weight instability itself. No associations between weight stability and psychiatric diagnoses were found in men.

DISCUSSION

Weight instability is related to mental and physical health concerns for both sexes. It was also specifically associated with depression and eating pathology in women.

Short sleep duration as a possible cause of obesity: critical analysis of the epidemiological evidence

Systematic literature search for epidemiological evidence for an association of short sleep with weight gain and eventual development of obesity provided 71 original studies and seven reviews of various subsets of these studies. We have summarized the evidence for such an association with particular emphasis on prospective studies. The studies showed that short sleep duration is consistently associated with development of obesity in children and young adults, but not consistently so in older adults. We have identified critical aspects of the evidence, and assessed the possibility for interpretation of the evidence in terms of causality. We have discussed the requirement of temporal sequence between putative exposure and outcome and the implications of the time lag between them, the problems in adequate measurements of exposure and effects, the possible bidirectional causal effects, the necessary distinction between confounders and mediators, the possible confounding by weight history, and the possibility of common or upstream underlying causes. In conclusion, causal interpretation of the association is hampered by fundamental conceptual and methodological problems. Experimental studies may elucidate mechanisms, but adequate coverage of the entire pathway from sleep curtailment through obesity development is not feasible. Randomized trials are needed to assess the value of targeted interventions.

Weight cycling during growth and beyond as a risk factor for later cardiovascular diseases: the 'repeated overshoot' theory

In people trying to lose weight, there are often repeated cycles of weight loss and regain. Weight cycling is, however, not limited to obese adults but affects people of normal weight, particularly young women, who are unhappy with their appearance. Furthermore, the onset of a pattern of weight cycling is shifting towards younger ages, owing to the increasing prevalence of overweight and obesity in children and adolescents, and the pressure from the media and society for a slim image even for normal weight children. Although there is still controversy whether weight cycling promotes body fat accumulation and obesity, there is mounting evidence from large population studies for increased cardiovascular risks in response to a behavior of weight cycling. Potential mechanisms by which weight cycling contributes to cardiovascular morbidity include hypertension, visceral fat accumulation, changes in adipose tissue fatty acid composition, insulin resistance and dyslipidemia. Moreover, fluctuations in blood pressure, heart rate, sympathetic activity, glomerular filtration rate, blood glucose and lipids that may occur during weight cycling--with overshoots above normal values during weight regain periods--put an additional load on the cardiovascular system, and may be easily overlooked if humans or animals are studied during a state of relatively stable weight. Overshoot of those risks factors, when repeated over time, will stress the cardiovascular system and probably contribute to the overall cardiovascular morbidity of weight cycling.

Meat consumption and prospective weight change in participants of the EPIC-PANACEA study

BACKGROUND

Meat intake may be related to weight gain because of its high energy and fat content. Some observational studies have shown that meat consumption is positively associated with weight gain, but intervention studies have shown mixed results.

OBJECTIVE

Our objective was to assess the association between consumption of total meat, red meat, poultry, and processed meat and weight gain after 5 y of follow-up, on average, in the large European population who participated in the European Prospective Investigation into Cancer and Nutrition-Physical Activity, Nutrition, Alcohol, Cessation of Smoking, Eating Out of Home and Obesity (EPIC-PANACEA) project.

DESIGN

A total of 103,455 men and 270,348 women aged 25-70 y were recruited between 1992 and 2000 in 10 European countries. Diet was assessed at baseline with the use of country-specific validated questionnaires. A dietary calibration study was conducted in a representative subsample of the cohort. Weight and height were measured at baseline and self-reported at follow-up in most centers. Associations between energy from meat (kcal/d) and annual weight change (g/y) were assessed with the use of linear mixed models, controlled for age, sex, total energy intake, physical activity, dietary patterns, and other potential confounders.

RESULTS

Total meat consumption was positively associated with weight gain in men and women, in normal-weight and overweight subjects, and in smokers and nonsmokers. With adjustment for estimated energy intake, an increase in meat intake of 250 g/d (eg, one steak at approximately 450 kcal) would lead to a 2-kg higher weight gain after 5 y (95% CI: 1.5, 2.7 kg). Positive associations were observed for red meat, poultry, and processed meat.

CONCLUSION

Our results suggest that a decrease in meat consumption may improve weight management.

Frequent intentional weight loss is associated with higher ghrelin and lower glucose and androgen levels in postmenopausal women

Population-based studies suggest that repetitive cycling of weight loss and regain may be associated with future weight gain. Therefore, to better define the relationship between weight cycling, energy homeostasis, and future weight gain, we examined associations between frequent intentional weight loss and hormonal profiles in postmenopausal women. This cross-sectional study evaluated the relationship between a history of frequent weight loss and biomarkers, including serum glucose, insulin, leptin, and ghrelin, as well as sex steroid hormones. We hypothesized that frequent intentional weight loss would be associated with changes in normal appetite and body weight regulatory hormones, favoring increased appetite and weight gain. One hundred fifty-nine healthy, weight stable, sedentary, overweight, postmenopausal women who had been recruited for an exercise intervention participated in this study. History of intentional weight loss (frequency and magnitude) was assessed by questionnaire. Hormonal assays were performed by radioimmunoassay (insulin, leptin, ghrelin, estrogens, androgens, and dehydroepiandrosterone), chemiluminescence immunoassay (insulin-like growth factor-1), and immunometric assay (sex hormone binding globulin). Analysis of variance and regression analyses were used to investigate the relationship between weight loss history and metabolic hormones. A higher degree of weight cycling, characterized by the frequency of intentionally losing more than 10 lb, was associated with an appetite-stimulating hormonal profile, including higher concentrations of ghrelin (P trend = .04), lower glucose (P trend = .047), and to some extent, lower insulin (P trend = .08). Frequent weight loss was also associated with lower androgen concentrations, including androstenedione (P trend = .02), testosterone (P trend = .04), and free testosterone (P trend = .01). No independent associations between the concentrations of leptin or estrogens and weight cycling were observed. This study suggests that frequent intentional weight loss may affect hormones involved in energy regulation.

Short-term weight change and fluctuation as risk factors for type 2 diabetes in Finnish male smokers

Risk of weight change and fluctuation for type 2 diabetes was studied in a prospective study among 20,952 Finnish male smokers aged 50-69 years. Baseline data on lifestyle and medical history were collected, and height and weight measured. Weight was measured thrice after the baseline, 1 year apart. Weight change was defined as the slope of the regression line fitted to the four measurements and weight fluctuation as the root-mean-square-error deviation from this line. Incident cases of diabetes were identified from a national medication reimbursement register; 535 cases up to 9 years' follow-up. The Cox proportional hazards model served to estimate relative risk [RR, 95% confidence interval (CI)]. Weight gain and fluctuation associated with higher risk for diabetes, multivariate RR = 1.77, 95% CI 1.44-2.17, for weight gain of at least 4 kg compared with those of weight change less than 4 kg, and RR = 1.64, 95% CI 1.24-2.17 in the highest weight fluctuation quintile compared to the lowest. These RRs remained similar when weight change and fluctuation were adjusted for each other. Large weight fluctuation increased the risk of diabetes both in men who gained weight (>or=4 kg), had stable weight (+/- <4 kg), and lost weight (>or=4 kg); RR = 2.17, 95% CI 1.60-2.94, RR = 1.47, 95% CI 1.14-1.91, and RR = 2.04, 95% CI 1.47-2.83, respectively, compared to those with stable weight and moderate fluctuation. Short-term weight gain and large weight fluctuation are independent risk factors for diabetes.

Patterns of weight control strategies predict differences in women's 4-year weight gain

The purpose of this study was to explore whether differences in patterns of weight control strategies predict 4-year weight change among women. Participants (N = 176), were assessed at baseline and biennially on three occasions. Weight control strategies were assessed by the Weight Loss Behavior Scale. Height and weight were measured to calculate BMI. Latent class analysis (LCA) identified groups of women differing in their reported weight control strategies. Repeated measures were employed to examine the relationship between using different types of weight control strategies and weight change before and after adjusting for education, income, and initial BMI. LCA yielded a three-group solution: use of none (N), healthy (H), and healthy plus unhealthy (H+U) weight control strategies. The N group had the lowest initial BMIs. Women's pattern of weight gain differed by latent group membership after adjusting for covariates: H+U group gained significantly more weight (4.56 kg) than the N group (1.51 kg) and H group (1.02 kg). Similar patterns emerged predicting weight change between years 2 and 4: H+U group gained significantly more weight (2.86 kg) than the H group (0.03 kg) and N group (0.44 kg). H+U weight control group had higher scores on weight concerns, dietary restraint, and eating attitudes than women in the H or N groups. These findings provide evidence that self-reported weight control attempts do not necessarily lead to large weight gains; rather the amount of weight gain may depend on the type of weight control strategies that women are practicing.

Effect of dietary fatty acid intake on prospective weight change in the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition

Objective

To evaluate the association between fatty acid (α-linolenic acid (ALA), EPA, DHA, palmitic, stearic, oleic, linoleic and arachidonic acids) intake and prospective weight change in the Heidelberg cohort of the European Prospective Investigation into Cancer and Nutrition.

Design

Prospective cohort study with mean follow-up time of 6·5 years. In a total of 9182 men and 10867 women aged 35 to 64 years, from body weight measurement at recruitment and calibrated body weight during follow-up, weight change was expressed as mean annual weight change relative to baseline weight (%/year) and categorised into four groups (weight loss, <−2·5%/5 years; stable weight, between −2·5 and +2·5%/5 years; small weight gain, ≥2·5 to <7·5%/5 years; large weight gain, ≥7·5%/5 years). Energy-adjusted dietary fatty acid intake data were estimated from the FFQ completed at baseline. Multivariate linear regression models as well as multinomial logistic regression analyses (carbohydrate replacement models) were conducted.

Results

Stearic acid intake was linearly associated with weight gain (P < 0·01) in men and women. Linear associations also existed for ALA and arachidonic acid intake, significantly so in women. In multinomial models, women in the highest tertile of ALA and stearic acid intake showed increased OR (95 % CI) for small weight gain (1·16 (0·94, 1·88) and 1·24 (1·08, 1·43), respectively), and large weight gain (1·39 (1·03, 1·88) and 1·56 (1·27, 1·90), respectively), whereas OR were non-significantly increased in men. Dietary intake of ALA was inversely associated with large (0·80 (0·65, 0·99)) weight gain in women only.

Conclusions

These results suggest differential effects of single dietary fatty acids on prospective weight gain in adults.

Difference of body compositional changes according to the presence of weight cycling in a community-based weight control program

Many obese people who try to control body weight experience weight cycling (WC). The present study evaluated the importance of WC in a community-based obesity intervention program. We analyzed the data of 109 Korean participants (86% women) among 177 subjects who had completed a 12-week intervention program at two public health centers in Korea from April to December, 2007. Completion of a self-administrated questionnaire at baseline was used to obtain anthropometric measurements, and laboratory testing was done before and after the program. Differences in body composition change and obesity-related life style between the two groups were compared with respect to WC and non-weight cycling (NWC). After 12 weeks, both groups showed reductions in weight, waist circumference, and body mass index. The group differences were not significant. However, significant differences were evident for the WC group compared to the NWC group in fat percent mass (WC vs. NWC, -3.49+/-2.31% vs. -4.65+/-2.59%, P=0.01), fat free mass (WC vs. NWC, -0.95+/-1.37 kg vs. -0.38+/-1.05 kg, P=0.01), and total cholesterol (WC vs. NWC, -3.32+/-14.63 vs. -16.54+/-32.39, P=0.005). In conducting a community-based weight control program that predominantly targets women, changes of body composition and total cholesterol may be less effective in weight cyclers than in non-weight cyclers.

Factors that may impede the weight loss response to exercise-based interventions

The results of exercise programmes designed to reduce body fat are disappointing. However, the reporting of weight loss as mean values disguises those individuals who do lose significant amounts of fat. Why some participants produce significant exercise-induced fat loss whereas others lose little or increase fat stores is likely to be an outcome of a range of behavioural (e.g. sleep deprivation, caloric intake), inherited (e.g. muscle fibre type, gender) and physiological (e.g. hyperinsulinaemia, hypothyroidism) factors. The following review highlights possible factors involved in weight loss and discusses how individual differences may determine the extent of weight loss after an exercise intervention. Finally, implications for the treatment and prevention of obesity are discussed.

Weight management strategies for women: a review for nurses

Upon completion of this activity, the learner will be able to: 1. Cite the statistics surrounding overweight and obesity and list the potential health effects of overweight and obesity. 2. List and explain different strategies for weight loss, including their risks and benefits as shown by the current evidence. 3. List effective strategies for maintaining weight loss and cite examples from the literature.

Fruit and vegetable intakes and subsequent changes in body weight in European populations: results from the project on Diet, Obesity, and Genes (DiOGenes)

BACKGROUND

High fruit and vegetable intakes may limit weight gain, particularly in susceptible persons, such as those who stop smoking.

OBJECTIVE

The objective was to assess the association of fruit and vegetable intake with subsequent weight change in a large-scale prospective study.

DESIGN

The data used were from 89,432 men and women from 5 countries participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). The association between fruit and vegetable intake and weight change after a mean follow-up of 6.5 y was assessed by linear regression. Polytomous logistic regression was used to evaluate whether fruit and vegetable intake relates to weight gain, weight loss, or both.

RESULTS

Per 100-g intake of fruit and vegetables, weight change was -14 g/y (95% CI: -19, -9 g/y). In those who stopped smoking during follow-up, this value was -37 g/y (95% CI: -58, -15 g/y; P for interaction < 0.0001). When weight gain and loss were analyzed separately per 100-g intake of fruit and vegetables in a combined model, the odds ratios (95% CIs) were 0.97 (0.95, 0.98) for weight gain > or =0.5 and <1 kg/y, 0.94 (0.92, 0.96) for weight gain > or =1 kg/y, and 0.97 (0.95, 0.99) for weight loss > or =0.5 kg/y. In those who stopped smoking during follow-up, the odds ratios (95% CIs) were 0.93 (0.88, 0.99), 0.87 (0.81, 0.92), and 0.97 (0.88, 1.07), respectively (P for interaction < 0.0001).

CONCLUSIONS

Fruit and vegetable intake relates significantly, albeit weakly inversely, to weight change. For persons who stop smoking, high fruit and vegetable intakes may be recommended to reduce the risk of weight gain.

Obesity and smoking: comparing cessation treatment seekers with the general smoking population

Obesity and smoking represent the leading preventable causes of morbidity and mortality in the United States. This study compared the prevalence of obesity among smokers seeking cessation treatment (n=1,428) vs. a general population (n=4,081) of never smokers, former smoker, and current smokers. Data from treatment-seeking smokers in the Wisconsin Smokers' Health Study (WSHS) and individuals who completed the National Health and Nutrition Examination Survey (NHANES) 2005-2006 were pooled and obesity rates and other health characteristics were compared. The prevalence of obesity was significantly higher among WSHS treatment-seeking smokers (36.8%) vs. NHANES current smokers (29.6%), but the obesity rates of WSHS treatment-seeking smokers did not differ from NHANES former smokers (36.5%) or never smokers (36.5%). Treatment-seeking smokers were more likely to be female and to have higher educational attainment compared to NHANES participants. Analysis of health characteristics revealed that treatment-seeking smokers had higher levels of dietary fiber and vitamin C and lower blood levels of total cholesterol, triglycerides, and fasting glucose compared to NHANES current smokers. Results suggest that treatment-seeking smokers may have a different health profile than current smokers in the general population. Health care providers should be aware of underlying heath issues, particularly obesity, in patients seeking smoking cessation treatment.

Conference on "Multidisciplinary approaches to nutritional problems". Symposium on "Diabetes and health". Challenges in the study of causation of obesity

Use of the energy balance equation for understanding the causation of obesity is discussed. Its basis on the thermodynamic laws is expressed in mathematical models for body-weight changes. Only a very small net energy surplus per time unit constitutes the energy deposition during weight gain, making measurements of its components difficult. The physical laws provide exact quantitative relationships between energy intake, energy expenditure and deposition of energy, but cannot disentangle the initiating and driving forces of the energy imbalance, which may also be an active storage of fat in adipose tissue. These and various other limitations of the energy balance model warrant cautiousness in using the model in studies of obesity causation. Weight gain may be self-promoting and mathematical feedback models allowing estimation of such effects show that they are realistic. Predisposition and susceptibility should be distinguished, and susceptibility as a modifiable predisposition, the genetic and environmental contribution to predisposition and its usefulness as targets for prevention and treatment are discussed. Current progress in unravelling genetic predisposition, the complex genetically-determined mechanisms, the slower progress in unravelling the environmental influences, the different nature of genetic and environmental influences, the possible pathways of environmental influences and the environmental influences as mediators of genetic effects are addressed. The evidence behind the prevailing concept of the 'obesogenic' environment is critically analysed. Finally, particular opportunities for the identification of the causes of the obesity epidemic by detailed analysis of an observed irregular development of the epidemic over long time periods are presented, and evidence for predisposition as a result of postnatal environmental influences is inferred from these studies.

Telephone-Based Diet and Exercise Coaching and a Weight-Loss Supplement Result in Weight and Fat Loss in 120 Men and Women

Purpose.

Determine the effects of telephone-based coaching and a weight-loss supplement on the weight and body fat (BF) of overweight adults.

Design.

Randomized, placebo-controlled experiment with assessments at baseline, 2 months, and 4 months.

Setting.

Community.

Subjects.

Sixty overweight or obese men and 60 overweight or obese women, 25 to 60 years old.

Intervention.

Eleven 30-minute telephone coaching sessions were spaced throughout the study; the initial conversation lasted 60 to 90 minutes. Supplement or placebo capsules were taken daily over the 17 weeks.

Measures.

Weight was measured using an electronic scale, and BF was assessed using dual energy x-ray absorptiometry.

Results.

Subjects taking the placebo lost 1.8 + 3.3 kg of weight and 0.7 + 2.2 kg of BF, whereas supplement users lost more: 3.1 + 3.7 kg of weight (F = 4.1, P = .045) and 1.7 + 2.6 kg of BF (F = 4.4, p = .039). Participants receiving no coaching lost 1.8 + 3.3 kg of weight and 0.7 + 2.2 kg of BF, whereas adults receiving coaching lost more: 3.2 + 3.6 kg of weight (F = 4.8, p = .032) and 1.6 + 2.5 kg of BF (F = 4.2, p = .044). Adults receiving both the supplement and coaching had the greatest losses of weight and BF, suggesting an additive effect (F = 3.2, p = .026; F = 2.9, p = .039, respectively).

Conclusions.

Both treatments, coaching and the supplement, viewed separately and in combination, worked to help subjects lose weight and BF. Adults can be educated and motivated via telephone to change behaviors leading to weight loss, and a weight-loss supplement can be included to increase success.

Intentional weight loss and mortality among initially healthy men and women

Most prospective observational studies suggest that weight loss increases the risk of premature death among obese individuals. This is surprising because clinical studies show that weight loss generally leads to overall improvements in cardiovascular risk factors. It is sometimes argued that the increased mortality observed with weight loss must depend on confounding or poor study designs. This review was conducted to summarize results from studies on intentional weight loss and mortality among healthy individuals, while carefully considering the designs and problems in these studies. Evaluation criteria with a rating scale were developed. Of the studies evaluated, two found decreased mortality with intentional weight loss, three found increased mortality, and four found no significant associations between intentional weight loss and total mortality. Thus, it is still not possible for health authorities to make secure recommendations on intentional weight loss. More studies designed to specifically address this issue are warranted.

Weight history of patients with newly diagnosed Type 2 diabetes

AIMS

To estimate and illustrate how the 10 years of weight change immediately preceding diabetes diagnosis vary with weight at the age of 20 years and with socio-demographic variables, risk factors and comorbidities at diagnosis.

METHODS

Data were from a population-based cohort of 1320 persons newly diagnosed with diabetes aged > or = 40 years. Patients' weight at diagnosis was measured by the doctor, while patients recalled their weight approximately 1, 5 and 10 years prior to diagnosis and at age 20 years.

RESULTS

Median weight gain from age 20 years to diabetes diagnosis at median age 65.3 years was 14.7 kg (interquartile range 6.0-23.0). Women gained weight more than men, and the lower the weight at age 20 years, the greater the weight gain. The average weight gain from 10 years prior to diabetes diagnosis until diagnosis, however, was only 1 kg and decreased markedly with age. These 10 years of weight change were also associated with sex and the following baseline characteristics: diagnostic plasma glucose, urinary glucose, urinary albumin, fasting triglycerides, systolic blood pressure, smoking habits, and presence of diabetic retinopathy.

CONCLUSIONS

The results add to the evidence that it is important to advise young patients in particular, especially women, who have gained and sustained considerable weight to curb this upward weight trend in order to prevent the development of diabetes.

Consequences of smoking for body weight, body fat distribution, and insulin resistance

Our aim was to critically evaluate the relations among smoking, body weight, body fat distribution, and insulin resistance as reported in the literature. In the short term, nicotine increases energy expenditure and could reduce appetite, which may explain why smokers tend to have lower body weight than do nonsmokers and why smoking cessation is frequently followed by weight gain. In contrast, heavy smokers tend to have greater body weight than do light smokers or nonsmokers, which likely reflects a clustering of risky behaviors (eg, low degree of physical activity, poor diet, and smoking) that is conducive to weight gain. Other factors, such as weight cycling, could also be involved. In addition, smoking increases insulin resistance and is associated with central fat accumulation. As a result, smoking increases the risk of metabolic syndrome and diabetes, and these factors increase risk of cardiovascular disease. In the context of the worldwide obesity epidemic and a high prevalence of smoking, the greater risk of (central) obesity and insulin resistance among smokers is a matter of major concern.

Association of cognitive restraint with ghrelin, leptin, and insulin levels in subjects who are not weight-reduced

Despite widespread efforts at weight loss, the prevalence of obesity continues to rise. Restrained eating is a pattern of attempted weight control characterized by cognitive restriction of food intake that has paradoxically been linked with overeating and/or weight gain. It is not known whether restrained eating is associated with abnormalities in appetite-regulating hormones, independent of its effects on body weight. To address this question, we assessed cognitive restraint using the Three-Factor Eating Questionnaire and obtained fasting measurements of ghrelin, leptin and insulin from 24 healthy, non-obese (body mass index (BMI) 19.7 to 29.6 kg/m(2)) adult subjects who were at a stable, lifetime maximum weight. We chose to study subjects at stable maximum weight to avoid the secondary effects of weight reduction on body-weight regulating hormones. Subjects were classified by cognitive restraint scale score into Low, Indeterminate, and High Restraint groups. Higher ghrelin levels were significantly associated with restraint in an unadjusted model (P=0.004) and after adjustment for BMI (P=0.007). No relationships were found between restraint scores and either leptin (P=0.75) or insulin (P=0.36). These findings show an orexigenic hormonal profile in restrained eaters, independent of changes in body weight.

Effects of leucine and phenylalanine supplementation during intermittent periods of food restriction and refeeding in adult rats

Although many studies have shown that amino acid ingestion acutely stimulates protein anabolism, only few studies have investigated whether long-term supplementation promotes changes in body composition. We therefore tested the hypothesis that l-leucine (LEU) and l-phenylalanine (PHE) supplementation might have a positive impact on the body composition of rats submitted to intermittent periods of food restriction and refeeding (weight cycling or WC). The WC protocol comprised three cycles, each consisting of 1 week of 50% food restriction followed by 2 weeks of ad libitum ingestion. The groups submitted to WC ingested the control diet (WC-CON) or the diet supplemented with LEU+PHE (WC-AA). A pair-fed group receiving the control diet (PF-CON) was used as a reference for the effects of WC. Although food intake was the same in all groups, higher body weight and energy efficiency were observed in the WC-AA group compared to the PF-CON and WC-CON groups although not significantly in relation to the latter. These results were the consequence of a significant increase of lean body mass and body protein content in the WC-AA group compared to the PF-CON and WC-CON groups. The WC-CON and WC-AA groups presented 36.1% and 18.9% more body fat, respectively, than the PF-CON group but this difference was not significant. Neither fasting insulin nor glucose concentration nor postprandial insulin secretion was significantly affected by the supplemented diet. In conclusion, supplementation with LEU+PHE improved the body composition profile of rats submitted to WC, mainly by increasing lean body mass and body protein content.

Weight cycling and 6-year weight change in healthy adults: The Aerobics Center Longitudinal Study

OBJECTIVE

To determine the longitudinal relationship between a reported history of weight cycling and the trajectory of weight in a group of normal-weight to obese women and men.

RESEARCH METHODS AND PROCEDURES

This was a clinic-based cohort study conducted over 6 years. Subjects were healthy women (n = 141) and men (n = 797) age 20 to 78 years who completed at least four comprehensive medical exams at the Cooper Clinic (Dallas, TX) between 1987 and 2003. Weight loss history was reported, and body weight was measured at all examinations. Weight cycling status was derived from weight loss history and defined as > or = five episodes of weight loss of > or = 2.3 kg/episode. Using linear mixed effects models, weight at each examination was regressed on weight cycling status separately for women and men while controlling for selected covariables.

RESULTS

Baseline BMI was 23 and 21 kg/m2 among cycling and non-cycling women and was 27 and 25 kg/m2 among cycling and non-cycling men, respectively. We observed a non-significant difference (p = 0.09) in women by cycling status (average weight gain = 0.5 and 0.2 kg/yr among cyclers and non-cyclers, respectively) and no difference in weight gain over time among men by cycling status (average weight gain = 0.2 kg/yr among both groups, p = 0.99). Higher baseline cardiorespiratory fitness level and increased fitness over the follow-up were associated with attenuated weight gain in both women and men.

DISCUSSION

In healthy, middle-aged individuals, a history of weight cycling does not seem to increase the risk of long-term weight gain in men; however, this relation needs to be studied further in women.

The definition of weight maintenance

There is currently no consensus on the definition of weight maintenance in adults. Issues to consider in setting a standard definition include expert opinion, precedents set in previous studies, public health and clinical applications, comparability across body sizes, measurement error, normal weight fluctuations and biologic relevance. To be useful, this definition should indicate an amount of change less than is clinically relevant, but more than expected from measurement error or fluctuations in fluid balance under normal conditions. It is an advantage for the definition to be graded by body size and to be easily understood by the public as well as scientists. Taking all these factors into consideration, the authors recommend that long-term weight maintenance in adults be defined as a weight change of <3% of body weight.

Weight cycling of athletes and subsequent weight gain in middleage

OBJECTIVE

To study the effects of repeated cycles of weight loss and regain as young adults on long-term weight development.

DESIGN

A follow-up study with questionnaires in 1985, 1995 and 2001.

SETTING

Finland.

SUBJECTS

A national cohort of 1838 male elite athletes who had represented Finland in major international sport competitions in 1920-1965, including 370 men engaged in sports in which weight-related performance classes are associated with weight cycling (boxers, weight lifters and wrestlers; further called as weight cyclers), and 834 matched control men with no athletic background.

OUTCOME MEASURE

Weight change since the age of 20 years, body mass index (BMI) and prevalence of obesity and overweight.

RESULTS

The weight cyclers gained 5.2 BMI units from age 20 years to their maximum mean weight, which was at age 58.7 years. Corresponding figures for the controls were 4.2 BMI units at 58.5 years and for other athletes 3.3 BMI units at age 62.5 years. The proportion of obese (BMI> or =30 kg/m(2)) subjects was greatest among the weight cyclers both in 1985 and 1995. In 2001, the weight cyclers were more often obese than other athletes, but did not differ from the controls. The odds ratio for the weight cyclers to be obese compared to other athletes in 1985 was 3.18 (95% confidence intervals 2.09-4.83), and compared to the controls 2.0 (1.35-2.96). The enhanced weight gain of the weight cyclers was not accounted for by present health habits (smoking, alcohol use, use of high-fat milk or physical activity) or weight at age 20 years.

CONCLUSIONS

Repeated cycles of weight loss and regain appear to enhance subsequent weight gain and may predispose to obesity. Chronic dieting with weight cycling may be harmful for permanent weight control.

Short-term weight changes in community-dwelling older adults: the Health, Aging, and Body Composition Weight Change Substudy

BACKGROUND

The frequency and short-term natural history of weight loss in community-dwelling older adults have not been described. Unintentional weight loss may be more likely to continue than intentional weight loss.

OBJECTIVES

The present substudy described the frequency of a > or = 5% loss or gain in body weight in community-dwelling older adults at an annual examination of the Health, Aging, and Body Composition (Health ABC) Study and 6 mo later. The weight-management practices used by the participants were also described.

DESIGN

A total of 522 older adults with either a > or = 5% weight gain (n = 116) or a > or = 5% weight loss (n = 171) in the previous year were compared with a random sample of weight-stable older adults (< 5% weight loss or gain, n = 235) at the fourth annual visit of the ongoing Health ABC Study. The participants' weight-loss intention and weight-management practices were assessed by an interview. The participants' weight was reassessed 6 mo later.

RESULTS

Compared with the weight-stable participants, the participants who had lost or gained weight at the substudy baseline were more likely to have subsequent weight changes. The direction of the subsequent weight change, however, was more likely toward either maintenance of or recovery from the previous weight change. Only 4% of the participants who gained weight and 11% of those who lost weight continued to gain or lose weight, respectively. Continued weight loss was more common in the participants with unintentional weight loss than in those with intentional weight loss, but the difference was not significant.

CONCLUSIONS

Weight changes were common, but most participants, including those who unintentionally lost weight, maintained their weight change or resolved their weight change in 6 mo. Unintentional weight loss appears less likely to resolve than other weight changes.

Prevalence of weight cycling and its relation to health indicators in Finland

OBJECTIVE

This study was performed to identify weight cyclers and to assess the prevalence of weight cycling and its relation to health indicators in Finnish adults.

RESEARCH METHODS AND PROCEDURES

Data for the study consisted of 3320 men and 3540 women (25 to 64 years of age). The subjects went through a health examination, and data on intentional weight losses and regains during the last 10 years were collected by a questionnaire. The subjects were divided into five groups: severe weight cyclers (weight loss >/= 5 kg at least three times with regain), mild weight cyclers (weight loss >/= 5 kg one to two times and regain), successful dieters (weight loss >/= 5 kg with no regain), nonobese nondieters, and obese nondieters.

RESULTS

Approximately 7% of men and 10% of women were defined as severe weight cyclers, and an additional 11% and 19% were defined as mild weight cyclers, respectively. In men, 20% of severe weight cyclers and 15% of obese nondieters perceived their health as poor, whereas in other groups, these proportions were <10%. In both sexes, severe weight cyclers seemed to have visited a doctor more frequently than nonobese nondieters. Severe weight cyclers were also more likely to use some medication compared with other groups.

DISCUSSION

Weight cycling is more common in women than in men, and it seems to be associated with more regular visits to a doctor and poor self-perceived health. However, because of the cross-sectional design of the study, causal conclusions cannot be drawn.

Weight cycling in treatment-seeking obese persons: data from the QUOVADIS study

OBJECTIVE

To determine parameters of weight history useful for the assessment of weight cycling and their association with psychological distress and binge eating.

DESIGN

Cross-sectional.

SUBJECTS

A total of 1889 treatment-seeking obese subjects, enrolled by 25 Italian centers (78% female subject), aged 20-65 y (median 45); 1691 reported previous efforts to lose weight (median age of first dieting, 30 y).

MEASUREMENTS

The number of yearly attempts to lose weight, weight gain since age 20 y, cumulative weight loss and gain were checked by a predefined structured interview. Psychological distress was tested by means of Symptom Check-List 90 (SCL-90), Binge Eating Scale (BES) and Three Factor Eating Questionnaire (TFEQ).

RESULTS

Differences in anthropometric, clinical and psychological parameters were observed in relation to previous attempts to lose weight. Patients in the upper quartile of parameters of weight history were considered weight cyclers. In multivariate logistic regression analysis, after correction for age, sex and BMI, a high BES score was the only factor systematically associated with a high frequency of dieting (OR, 1.70; 95% confidence interval, 1.22-2.36; P=0.022), with higher cumulative weight loss (1.42; 1.12-1.80; P=0.003) and cumulative weight gain (1.38; 1.06-1.79; P=0.017). However, the sensitivity, specificity and positive predictive value of a high BES score were very low to detect cyclers. Weight cycling did not carry a higher risk of complicating diseases.

CONCLUSIONS

Weight cycling is associated with psychological distress, and binge eating independently increases the risk, but cannot be used to predict cycling. Also, obese patients who do not experience overeating as a loss of control discontinue treatment or regain weight following therapy.

Association of weight change, weight control practices, and weight cycling among women in the Nurses' Health Study II

OBJECTIVE

To assess the association of weight cycling with weight change, weight control practices, and bulimic behaviors.

METHODS

A nested study of 2476 young and middle-aged women in the Nurses' Health Study II who provided information on intentional weight losses between 1989 and 1993.

SAMPLE

In total, 224 women who were severe cyclers, 741 women who were mild cyclers, 967 age- and BMI-matched controls (noncyclers), and 544 women who did not weight cycle and maintained their weight between 1989 and 1993 completed a questionnaire in 2000-2001 assessing recent intentional weight losses, weight control practices, and weight concerns.

RESULTS

After controlling for age and body mass index (BMI) in 1993, when weight cycling was initially assessed, mild cyclers gained an average of 6.7 pounds (lbs) more and severe cyclers gained approximately 10.3 lbs more than noncyclers between 1993 and 2001. Weight cyclers preferred to change their diet rather than to exercise to control their weight. Severe weight cyclers were less likely than noncyclers to use frequent exercise as a weight control strategy (odds ratio [OR]=0.8, 95% confidence interval (CI) 0.6-1.1). Cyclers were also more likely than noncyclers to engage in binge eating (mild cyclers: OR=1.8, 95% CI 1.4-2.4; and severe cyclers: OR=2.5, 95% CI 1.7-3.5). Independent of weight cycling status, age, and BMI, women who engaged in binge eating gained approximately 5 lbs more than their peers (P<0.001).

CONCLUSIONS

Weight cycling was associated with greater weight gain, less physical activity, and a higher prevalence of binge eating. Low levels of activity and binge eating may be partially responsible for the large amount of weight regained by weight cyclers.

Associations of short-term weight changes and weight cycling with incidence of essential hypertension in the EPIC-Potsdam Study

The aim of this study was to examine the relationships of short-term weight gain, weight loss, and weight cycling on the odds of developing hypertension. Normotensive middle-aged German men and women (n=12,362) of the European Prospective Investigation into Cancer and Nutrition-Potsdam Study were assigned to categories of 2-year short-term weight changes that were self-reported to have occurred prior to recruitment into the study (gain only, loss only, weight cycling, stable). After 2 years of follow-up after recruitment, 180 cases of incident essential hypertension were identified. In logistic regression models, odds ratios were estimated for the associations between short-term weight changes and risk of developing hypertension. Obesity status (BMI>or=30 or BMI<30 kg/m2) modified the associations between short-term weight change and incidence of diagnosed hypertension. Among obese individuals, short-term weight gain occurring during the 2 years prior to recruitment (OR=2.79, 95% CI 1.19-6.56), weight loss (OR=6.74, 95% CI 2.58-17.6) and weight cycling (OR=4.29, 95% CI 1.55-11.9) were strongly positively associated with incident hypertension, adjusted for age and gender, compared to obese individuals with short-term stable weight. No significant associations between short-term weight changes and risk of diagnosed hypertension were detected among non-obese individuals. Short-term weight changes appeared to present strong risk factors for developing hypertension among obese individuals. The effect seen for weight cycling supports the hypothesis that weight cycling increases the risk of hypertension. The finding for short-term weight loss may be explained by subsequent weight regain and needs further investigation.

Frequent intentional weight loss is associated with lower natural killer cell cytotoxicity in postmenopausal women: possible long-term immune effects

OBJECTIVE

Weight-loss attempts are likely to become more frequent as the prevalence of obesity rises. Repeated cycles of loss and gain are a common consequence of failed weight-loss attempts. The question of whether this pattern has negative health effects is unresolved. The objective of this research was to investigate associations between weight-loss history and current measures of immune function.

DESIGN

The study design was a cross-sectional study.

SUBJECTS

One hundred fourteen healthy, overweight, sedentary, postmenopausal women were recruited for an exercise intervention study and were currently weight stable.

METHODS

History of intentional weight loss was assessed by questionnaire. Flow cytometry was used to measure natural killer cell (NK) cytotoxicity at four effector-to-target (E:T) ratios and for enumerating and phenotyping lymphocytes. Multiple linear regression analysis was used to investigate associations between weight loss within the past 20 years and current immune function.

RESULTS

Women who reported ever intentionally losing >or=10 pounds had lower measured NK cytotoxicity than those who did not (24.7%+/-12.1% vs 31.1%+/-14.7%, respectively, at E:T 25:1; P=.01). Increasing frequency of previous intentional weight loss was associated with lower NK cytotoxicity (P=.003, trend). As an independent predictor, longer duration of recent weight stability was associated with higher NK cytotoxicity (21.6%+/-11.9%, 24.4%+/-11.0%, and 31.9%+/-14.4% for <or=2, >2 to <or=5, and >5 years of weight stability, respectively; P=.0002, trend). The frequency of weight loss episodes was also associated with differences in the number and proportion of NK cells.

CONCLUSIONS

This study provides evidence that frequent intentional weight loss may have long-term effects on immune function.

Self-reported dieting experiences of women with body mass indexes of 30 or more

Self-reported information on dieting experiences of 149 women with a body mass index (BMI) of 30 to 70 was gathered to refute the notion that obese women have made few serious attempts to lose weight and to see whether women with higher BMIs report more frequent dieting than women with lower BMIs. Participants completed questionnaires about lifetime dieting experiences and provided demographic information, including heights and weights. Statistical comparisons among categorical variables were made using chi(2) tests. Women with higher BMIs tended to start dieting before age 14 (P<.001) and had dieted more frequently (P<.01) than women with lower BMIs. Negative memories of dieting far outnumbered positive or neutral ones. When a patient has a history of dieting failure, dietetics professionals should consider focusing on improvements in metabolic fitness through lifestyle changes for chronic disease risk reduction rather than encouraging continued attempts to lose weight.

[Weight cycling during treatment of obese women]

Long-term treatment of obese patients shows that the majority of them regains weight or has weight cycling (WC). We have studied the frequency of WC (weight lost and regain of at least 5% of initial weight, IW) in 218 obese women selected from a University Hospital with a follow-up of >12 months admitted between 1992 and 2000. Patients with psychiatric, infectious or chronic disease (except metabolic syndrome), pregnancy, or using glucocorticoids were excluded. Mean age was 38+/-10 years (range 18 to 68) and the mean BMI was 41.0+/-6.6 kg/m2 (range 30 to 76). All were treated with a hypocaloric diet and increased physical activity. Anti-obesity medications were used in 61% of them for short periods of time. In the follow-up of 28+/-16 months (range 12 to 92 mo, median 23 mo), WC was observed in 62/218 (28.4%) of them and 53 had weight lost followed by weight regain. In the weight-cyclers, 59.1% of patients regained weight before the first year of treatment. WC was associated with alcohol consumption higher than 60 g/week, (RR 2.4; 95% CI= 1.2-4.7) but not with obesity class, smoking or smoke cessation. We conclude that WC is highly frequent and alcohol consumption is a predictive risk factor.

Variables predictive of adherence to diet and physical activity recommendations in the treatment of obesity and overweight, in a group of Spanish subjects

OBJECTIVE

To assess the factors that could predict a successful completion of a weight loss program.

STUDY DESIGN

A single-centered, cross-sectional, prospective study conducted over 4 y.

SUBJECTS

Data were obtained on 1018 overweight subjects (788 women, 230 men) aged 14.8-76.3 y (mean 38.4) and body mass index (BMI) of 31.7 (range 25.03-57.1) seeking help to lose weight at a specialist obesity clinic.

MATERIALS AND METHODS

A program involving a hypocaloric, Mediterranean diet was prescribed plus recommendations for free-time exercise and day-to-day activity. Follow-up was weekly until the desired weight loss was achieved ('successful completion') or the patient dropped-out of the program ('failure'). Cox's regression analysis was used to evaluate success and the variables included were compliance with the program, age, gender, initial BMI, physical activity, alcohol consumption, smoking habit, hypertension, diabetes, hypercholesterolemia, cardiovascular disease, previous dietary programs, cause of obesity, age at which excessive weight was first noted and parental obesity.

RESULTS

Factors predictive of completion were: gender (males responded better), previous dietary programs (predictive of dropout), initial BMI (higher index, lower completion), and age (younger age, poorer outcome). There was an interaction between parental obesity and offspring childhood obesity. Absence of parental obesity and adult-onset obesity had a higher probability of program completion.

CONCLUSIONS

In a standard weight reduction program the recommendations of dietary restriction and moderate exercise seems less effective for women, persons with high BMI, younger age groups and those who have had other attempts at weight loss. Poorest outcomes applied to those subjects with childhood obesity and who had obese parents.

Importance of smoking habits for longitudinal and age-matched changes in body mass index: a cohort study of Swedish men and women

BACKGROUND

Previous longitudinal studies of smoking and BMI have focused on smoking cessation. The aim of the present study was to disentangle the effects of long-term smoking on longitudinal changes and age-matched BMI differences (time period effects) in a nation-wide Swedish cohort.

METHODS

Men and women (n = 4349) ages 18-73 years reported height, weight, and smoking status for a baseline survey in 1980-1981. Eight and 16 years after baseline, follow-up surveys were conducted for 3244 (75%) of the 4349 subjects. Long-term smokers and long-term nonsmokers were compared with respect to longitudinal changes and age-matched BMI differences.

RESULTS

For middle-age adults, the longitudinal increases in BMI were smaller among long-term smokers than long-term nonsmokers regardless of gender. Among the elderly, the longitudinal decrease in BMI was greatest among long-term smokers. Among men, age-matched BMI differences between surveys were smaller for long-term smokers than for nonsmokers. Among women, however, age-matched BMI differences were greater for long-term smokers than for nonsmokers.

CONCLUSIONS

In middle-age subjects, longitudinal BMI increases are smaller among smokers than nonsmokers. During old age, the BMI of smokers decreases more than that of nonsmokers. Unknown factors related to gender contribute to larger time period effects of smoking in women than in men.