Serum lipophilic antioxidants levels are associated with leucocyte telomere length among US adults.

BACKGROUND: To examine the association between serum concentrations of antioxidant and telomere length (TL) in U.S adults. METHODS: Participants of the National Health and Nutrition Examination Survey (NHANES) with data available on TL measures from 2001 to 2002 were included. Serum lipophilic antioxidants level was measured using high performance liquid chromatography with photodiode array detection. We used analysis of co-variance and multivariable-adjusted linear regression models, accounting for the survey design and sample weights. RESULTS: Of the 5992 eligible participants, 47.5% (n = 2844) were men. The mean age was 46.9 years overall, 47.2 years in men and 46.6 in women (p = 0.071). In age, sex, race, education, marital status, adiposity, smoking, C-reactive protein adjusted linear regressions, antioxidant, serum α-carotene, trans-ß-carotene, cis- ß-carotene, ß-cryptoxanthin and combined Lutein/zeaxanthin were positively and significantly associated with TL (all p < 0.001). CONCLUSIONS: Our findings support a possible positive association between serum concentrations of lipophylic antioxidant and TL. The implications of this association deserve further investigation.

Impact of weight-related advice from healthcare professionals on body mass index of patients in the USA.

OBJECTIVES: Healthcare professionals (HCPs) can help promote healthy eating and active living in patients. This study assessed the effects of weight-related advice from HCPs on change in body mass index (BMI) of patients in the USA. STUDY DESIGN: A 1-year follow-up study of 20,002 adults who participated in a nationally representative survey between 2004 and 2008. METHODS: Using the 2004-2008 Medical Expenditure Panel Survey data, 1-year BMI and weight status changes were compared between patients who did and did not report receiving advice on exercise or on restricted intake of fat and cholesterol from their HCPs. RESULTS: Patients who received weight-related advice had a greater increase in BMI compared with those who did not receive weight-related advice. Stratified by the baseline weight status of patients (i.e. normal weight, overweight or obese), adverse direction of BMI change was only significantly associated with advice on exercise. Patients who received advice to exercise more were more likely to move to a higher weight status than remaining at the same weight status, compared with patients who did not receive advice to exercise more. CONCLUSION: This study did not find that weight-related advice from HCPs had a positive impact on BMI loss in patients. On the contrary, patients who reported receiving weight-related advice from HCPs had worse weight outcomes 1 year later than patients who did not report receiving weight-related advice. Further research is warranted to elucidate the role of weight-related advice from HCPs on lifestyle change and obesity prevention and control.

Motivating systems-oriented research on environmental and policy changes for obesity prevention.

BACKGROUND: Research on the types of interventions needed for population-level prevention of childhood obesity in complex societal systems can benefit from greater use of systems-science concepts and tools. OBJECTIVES: We report outcomes of a funding programme promoting incorporation of systems-science approaches into studies of imminent policy or environmental changes potentially impacting childhood obesity. METHODS: Seven funding cycles over 3 years yielded 172 initial submissions from 29 US states and 25 other countries were analyzed. RESULTS: Submissions focused primarily on aspects of school or child-care settings, parks and recreational settings, or access to healthy food; about half reflected attention to systems perspectives. CONCLUSIONS: Analysis of initial submissions as well as the 15 funded projects showed some success in motivating use of systems concepts and tools but suggested the need for a more focused effort to educate and prepare the childhood obesity prevention research community for this potentially crucial type of research.

Alternate-day versus daily energy restriction diets: which is more effective for weight loss? A systematic review and meta-analysis.

BACKGROUND: Alternate-day-fasting (ADF) has been proposed as an effective dieting method. Studies have found that it also can increase life span in rodents, and reduce inflammation in humans. The aim of this paper was to systematically review the efficacy of ADF compared to very-low-calorie dieting (VLCD) in terms of weight loss, and reduction of fat mass and fat-free mass. METHODS: Systematic review: PubMed literature searches were performed. Fixed review procedures were applied. Studies were evaluated for quality. Twenty-eight studies were included. Meta-analysis: 10/28 studies (four ADF and six matched VLCD) were further analyzed. RESULTS: After adjustment for BMI and duration, there was no significant difference in mean body weight loss (VLCD 0.88 kg more weight loss than ADF, 95% CI: -4.32, 2.56) or fat-free mass (VLCD 1.69 kg more fat-free mass loss than ADF, 95% CI: -3.62, 0.23); there was a significant difference observed in fat mass (ADF 3.31 kg more fat mass loss than VLCD, 95% CI: 0.05, 6.56). Meta-analysis showed that, among ADF studies, the pooled change in body weight, fat mass and fat-free mass was 4.30 kg (95% CI: 3.41, 5.20), 4.06 kg (95% CI: 2.99, 5.13) and 0.72 kg (95% CI: -0.07, 1.51), respectively, while among VLCD studies, the pooled change was 6.28 kg (95% CI: 6.08, 6.49), 4.22 kg (95% CI: 3.95, 4.50) and 2.24 kg (95% CI: 1.95, 2.52), respectively. CONCLUSIONS: Our results from both the systematic review and the meta-analysis suggest that ADF is an efficacious dietary method, and may be superior to VLCD for some patients because of ease of compliance, greater fat-mass loss and relative preservation of fat-free mass. Head-to-head randomized clinical trials are needed to further assess relative efficacy of these two approaches.

What childhood obesity prevention programmes work? A systematic review and meta-analysis.

Previous reviews of childhood obesity prevention have focused largely on schools and findings have been inconsistent. Funded by the US Agency for Healthcare Research and Quality (AHRQ) and the National Institutes of Health, we systematically evaluated the effectiveness of childhood obesity prevention programmes conducted in high-income countries and implemented in various settings. We searched MEDLINE®, Embase, PsycINFO, CINAHL®, ClinicalTrials.gov and the Cochrane Library from inception through 22 April 2013 for relevant studies, including randomized controlled trials, quasi-experimental studies and natural experiments, targeting diet, physical activity or both, and conducted in children aged 2-18 in high-income countries. Two reviewers independently abstracted the data. The strength of evidence (SOE) supporting interventions was graded for each study setting (e.g. home, school). Meta-analyses were performed on studies judged sufficiently similar and appropriate to pool using random effect models. This paper reported our findings on various adiposity-related outcomes. We identified 147 articles (139 intervention studies) of which 115 studies were primarily school based, although other settings could have been involved. Most were conducted in the United States and within the past decade. SOE was high for physical activity-only interventions delivered in schools with home involvement or combined diet-physical activity interventions delivered in schools with both home and community components. SOE was moderate for school-based interventions targeting either diet or physical activity, combined interventions delivered in schools with home or community components or combined interventions delivered in the community with a school component. SOE was low for combined interventions in childcare or home settings. Evidence was insufficient for other interventions. In conclusion, at least moderately strong evidence supports the effectiveness of school-based interventions for preventing childhood obesity. More research is needed to evaluate programmes in other settings or of other design types, especially environmental, policy and consumer health informatics-oriented interventions.

Proxy measures of vitamin D status - season and latitude - correlate with adverse outcomes after bariatric surgery in the Nationwide Inpatient Sample, 2001-2010: a retrospective cohort study.

OBJECTIVE: To investigate the association between adverse surgical outcomes following bariatric surgery and proxy measures of vitamin D (VitD) status (season and latitude) in the Nationwide Inpatient Sample (NIS). BACKGROUND: Obesity is an independent risk factor for VitD deficiency (25(OH)D < 20 ng ml-1). VitD deficiency compounds the chronic inflammation of obesity, increasing the risk of adverse outcomes following bariatric surgery. Epidemiology has long used season and latitude as proxies for group VitD, as VitD status is largely determined by sun exposure, which is greatest during summer and at the Equator. METHODS: We assessed proxy measures of group VitD status. We compared surgeries in VitD Summer (July to September), Winter (January to March), and Fall/Spring (October to December and April to June) and in the North (≥37°N) vs. the South (<37°N). RESULTS: We identified 932,091 bariatric surgeries; 81.2% were women and 74.4% were white. Sex was unequally distributed by season (p = 0.005). Median age was 43.0 years (all groups). Most surgeries occurred in the North (64.8%). Adverse outcome rates ranged from 0.01% (wound infections) to 39.4% [prolonged length of stay {LOS}]. Season was inversely associated with wound infection (p = 0.018) and dehiscence (p = 0.001). Extended LOS was inversely correlated with season (p < 0.001). These relationships held after adjustment. Prolonged LOS (p < 0.001) and any complication (p = 0.108) were more common in the North. CONCLUSIONS: We have demonstrated a graded relationship between seasonality and adverse outcomes following bariatric surgery. The association was strongest for dehiscence and prolonged LOS. These relationships held when using latitude. A prospective study measuring pre-operative 25(OH)D concentration would strengthen the case for causality in adverse surgical outcomes.

Effects of meal composition on postprandial incretin, glucose and insulin responses after surgical and medical weight loss.

BACKGROUND: Meal tolerance tests are frequently used to study dynamic incretin and insulin responses in the postprandial state; however, the optimal meal that is best tolerated and suited for hormonal response following surgical and medical weight loss has yet to be determined. OBJECTIVE: To evaluate the tolerability and effectiveness of different test meals in inducing detectable changes in markers of glucose metabolism in individuals who have undergone a weight loss intervention. METHODS: Six individuals who underwent surgical or medical weight loss (two Roux-en-Y gastric bypass, two sleeve gastrectomy and two medical weight loss) each completed three meal tolerance tests using liquid-mixed, solid-mixed and high-fat test meals. The tolerability of each test meal, as determined by the total amount consumed and palatability, as well as fasting and meal-stimulated glucagon-like peptide, glucose-dependent insulinotropic polypeptide, insulin and glucose were measured. RESULTS: Among the six individuals, the liquid-mixed meal was better and more uniformly tolerated with a median meal completion rate of 99%. Among the four bariatric surgical patients, liquid-mixed meal stimulated on average a higher glucagon-like peptide (percent difference: 83.7, 89), insulin secretion (percent difference: 155.1, 158.7) and glucose-dependent insulinotropic polypeptide (percent difference: 113.5, 34.3) compared with solid-mixed and high-fat meals. CONCLUSIONS: The liquid-mixed meal was better tolerated with higher incretin and insulin response compared with the high-fat and solid-mixed meals and is best suited for the evaluation of stimulated glucose homeostasis.

Effect of childhood obesity prevention programmes on blood lipids: a systematic review and meta-analysis.

We aimed to assess the effects of childhood obesity prevention programmes on blood lipids in high-income countries. We searched MEDLINE®, Embase, PsychInfo, CINAHL®, clinicaltrials.gov, and the Cochrane Library up to 22 April 2013 for relevant randomized controlled trials, quasi-experimental studies and natural experiments published in English. Studies were included if they implemented diet and/or physical activity intervention(s) with ≥1 year follow-up (or ≥6 months for school-based intervention studies) in 2-18-year-olds, and were excluded if they targeted only overweight/obese children, or those with a pre-existing medical condition. Seventeen studies were finally included. For total cholesterol, the pooled intervention effect was -0.97 mg dL(-1) [95% confidence interval (CI): -3.26, 1.32; P = 0.408]; for low-density lipoprotein cholesterol (LDL-C), -6.06 mg dL(-1) (95% CI: -11.09, -1.02; P = 0.018); for high-density lipoprotein cholesterol (HDL-C), 1.87 mg dL(-1) (95% CI: 0.39, 3.34; P = 0.013); and for triglycerides, -1.95 mg dL(-1) (95% CI: -4.94, 1.04; P = 0.202). Most interventions (70%) showed similar significant or no effects on adiposity- and lipids outcomes: 15% interventions improved both adiposity- and lipids outcomes; 55% had no significant effects on either. Childhood obesity prevention programmes had a significant desirable effect on LDL-C and HDL-C. Two-thirds of interventions showed similar significant or no effects in adiposity- and lipids outcomes. Assessing lipids outcomes provide additional useful information on obesity prevention programme benefits.

Association between obesity and kidney disease: a systematic review and meta-analysis.

This study aimed to comprehensively assess epidemiologic evidence on the relation between obesity and kidney disease (KD). From 247 retrieved articles via PubMed (1980-2006), 25 cohorts, 3 cross-sectional, and 19 case-control studies met inclusion criteria. Related data were extracted using a standardized protocol. We estimated the pooled relative risk (RR) and 95% confidence interval (95% CI) of KD for each body mass index (BMI) category compared with normal weight using meta-analysis models. Population attributable risk was also calculated. Compared with normal-weight individuals (18.5

Serum concentrations of retinol, alpha-tocopherol and the carotenoids are influenced by diet, race and obesity in a sample of healthy adolescents.

An important part of understanding the functions of vitamin A, vitamin E and the carotenoids in nutritional status assessment, health promotion and disease prevention is knowledge of factors that influence their distribution in human tissues. Our objective was to examine serum concentrations of these nutrients and compounds in a sample of 285 healthy participants, 12-17 y old, from three U. S. cities. Pearson correlations between diet measured with a food frequency questionnaire and serum nutrient concentrations among these adolescents (adjusted for total serum cholesterol, age, sex, race and body mass index) were as follows: retinol, 0.23; alpha-tocopherol, 0.16; alpha-carotene, 0.31; beta-carotene, 0.15; beta-cryptoxanthin, 0.38; lycopene, 0.08; and lutein + zeaxanthin, 0.25. Multivariate linear regression modeled associations of demographic, dietary and physiologic variables with serum concentrations of these nutrients. African-American participants had significantly lower concentrations of serum retinol (P < 0.001), alpha-tocopherol (P < 0.01) and alpha-carotene (P < 0.02), but higher concentrations of lutein + zeaxanthin (P = 0.001) compared with Caucasians. Obese participants had serum nutrient concentrations that were 2-10% (P < 0.05) lower than normal weight participants. Dietary intake was a significant predictor of all serum analytes (P < 0.01) except lycopene. These models explained 20% of the variability in serum retinol, 28% of the variability in serum alpha-tocopherol, and 14-24% of the variability in serum carotenoids.

Metabolic disharmony and mortality.

The concept of 'metabolic harmony' is introduced and conceptualized as the state in which indices of metabolic activity (i.e., serum glucose, cholesterol, systolic and diastolic blood pressure, body mass index) within an individual attain their expected values given the individual values on related variables. Its complement, 'metabolic disharmony' (i.e., the extent to which an individual's 'profile' of metabolic variables is jointly unusual in relation to their expected values) is operationalized via Mahalanbis' D(2 )statistic calculated on these indices of metabolic activity (plus age and sex). Analysis of a large (N = 5209) longitudinal (32 years) cohort study shows that, independent of the linear and quadratic effects of the aforementioned metabolic variables, the disharmony index (DI) significantly and strongly predicted hazard of death (chi(2)(1) = 20.05, P < 0.00005). That is, each 10 percentile increase in DI was associated with a 6.9% increase in the hazard rate. The association of DI to hazard rate was not materially altered when potential confounders (e.g., smoking status) were added to the model or when all subjects were included by imputing missing data. These results demonstrate that metabolic disharmony is associated with, and may cause, an increased hazard of death.

Behavioral approaches to the problems of obesity.

Obesity is a complex and increasingly prevalent disorder that can confer a number of medical, social, and psychological difficulties. As a result, an array of treatment strategies falling under the generic umbrella of "behavior therapy" have been developed and continue to be refined and expanded. In this article, different behavioral approaches to the problems of obesity are outlined and reviewed, specifically, those that target (a) body weight or composition, (b) lifestyle factors and other health-related variables, and (c) related psychological variables such as self-esteem and assertiveness, as well as negative attitudes toward obese persons held by nonobese individuals. For each of these targets of change, approaches to both individual- and group-level interventions are considered. Suggestions for future research and clinical work are offered. Throughout, the importance of conceptualizing obesity as a multifaceted problem is underscored. The necessity for explicit target goals when attempting to modify behavior is also highlighted.

Changes in diet, weight, and serum lipid levels associated with olestra consumption.

BACKGROUND: Specially manufactured low-fat and nonfat foods have become increasingly available over the past 2 decades and controversy has surrounded the issue of whether these products have beneficial or adverse effects on the health and nutritional status of Americans. METHODS: This study examines the association of olestra consumption with changes in dietary intakes of energy, fat, and cholesterol and changes in weight and serum lipid concentrations. Data are from a cohort of 335 participants in the Olestra Post-Marketing Surveillance Study sentinel site in Marion County (Indianapolis, Ind). Diet, weight, and serum lipid levels were assessed before the market release of olestra and 1 year later, after olestra-containing foods were widely available. Olestra intake at the 1-year follow-up was categorized as none, low (>0 to 0.4 g/d), moderate (0.4 to 2.0 g/d), and heavy (>2.0 g/d). RESULTS: Participants in the heavy olestra consumption category significantly reduced dietary intake of percentage of energy from fat (2.7 percentage points, P for trend,.003) and saturated fat (1.1 percentage points, P for trend,.02). Consumers in the highest category of olestra consumption had statistically significantly reduced total serum cholesterol levels of -0.54 mmol/L (-21 mg/dL)compared with -0.14 mmol/L (-5 mg/dL) among olestra nonconsumers (P for trend,.03). CONCLUSIONS: These results indicate that introduction of a new fat substitute (olestra) in the US market was associated with healthful changes in dietary fat intake and serum cholesterol concentrations among consumers who chose to consume olestra-containing foods.

Olestra consumption does not predict serum concentrations of carotenoids and fat-soluble vitamins in free-living humans: early results from the sentinel site of the olestra post-marketing surveillance study.

In 1996, the U.S. Food and Drug Administration approved olestra, a fat substitute, for use in snack foods. Previous studies had shown that olestra consumption could reduce absorption of carotenoids and fat-soluble vitamins. To determine the association between consumption of olestra-containing snack foods and serum concentrations of carotenoids and fat-soluble vitamins in a free-living population, we interviewed independent population-based cross-sectional samples of 1043 adults before olestra was available and 933 adults 9 mo after olestra snacks were introduced into the marketplace in Marion County, IN, the first major test market for olestra. A cohort composed of 403 adults from the first survey, oversampling those most frequently reporting olestra consumption during follow-up telephone interviews, completed a second survey. We assessed diet, lifestyle factors and olestra consumption, and collected blood for assays for the serum concentrations of six carotenoids, four fat-soluble vitamins and lipids. Nine months after the introduction of olestra into the marketplace, 15.5% of Marion County residents reported consuming an olestra-containing snack in the previous month, with a median frequency among consumers of 3.0 times per month. There were no significant associations or consistent trends for decreased serum carotenoids or fat-soluble vitamins associated with olestra consumption, although cohort members consuming >/=2 g/d of olestra had adjusted total serum carotenoids 15% lower compared with baseline. There were increases in serum vitamin K concentrations associated with olestra consumption (P = 0.03 in the cross section and P = 0.06 in the cohort). In summary, there was no statistically significant evidence in this free-living population of associations between olestra consumption and decreased serum concentrations of carotenoids and fat-soluble vitamins.

Weight-control behaviors among adults and adolescents: associations with dietary intake.

BACKGROUND: This study aimed to assess the prevalence of weight-control behaviors and their associations with overall dietary intake among adults and adolescents. METHODS: Participants included 3,832 adults and 459 adolescents from four regions of the United States. Cross-sectional data were collected on energy and nutrient intake, weight-control behaviors, body mass index (BMI), and sociodemographics. RESULTS: Current weight-control behaviors were reported by 52.7% of the study population (adult women, 56.7%; adult men, 50.3%; adolescent girls, 44.0%; adolescent boys, 36.8%). Weight-control behaviors were consistently and positively associated with socioeconomic status among adults, but not among adolescents. Among "dieters," unhealthy practices were reported by 22.7% of adult women, 21.3% of adult men, 30.4% of adolescent girls, and 18.5% of adolescent boys. Adults trying to control their weight reported healthier nutrient intakes than those not trying to control their weight, in particular when moderate weight-control methods were employed. Among adolescents, there were fewer differences across dieting status and these were not suggestive of healthier intakes among dieters than nondieters. CONCLUSIONS: Weight-control behaviors are reported by a large percentage of the population. Weight-control behaviors tend to be healthier among adults than among adolescents, in terms of the types of behaviors used and their impact on nutrient intakes. Obesity prevention interventions should emphasize the importance of using healthy weight-control practices.