The medical effects of modest weight reduction (approximately 10% or less) in patients with obesity-associated medical complications were reviewed. The National Library of Medicine MEDLINE database and the Derwent RINGDOC database were searched to identify English language studies that examined the effects of weight loss in obese patients with serious medical complications commonly associated with obesity (non-insulin dependent diabetes mellitus (NIDDM or type II), hypertension, hyperlipidemia, hypercholesterolemia, and cardiovascular disease). Studies in which patients experienced approximately 10% or less weight reduction were selected for review. Studies indicated that, for obese patients with NIDDM, hypertension or hyperlipidemia, modest weight reduction appeared to improve glycemic control, reduce blood pressure, and reduce cholesterol levels, respectively. Modest weight reduction also appeared to increase longevity in obese individuals. In conclusion, a large proportion of obese individuals with NIDDM, hypertension, and hyperlipidemia experienced positive health benefits with modest weight loss. For patients who are unable to attain and maintain substantial weight reduction, modest weight loss should be recommended; even a small amount of weight loss appears to benefit a substantial subset of obese patients.

Beneficial health effects of modest weight loss.

The prevalence of obesity in the United States and the world has risen to epidemic/pandemic proportions. This increase has occurred despite great efforts by healthcare providers and consumers alike to improve the health-related behaviors of the population and a tremendous push from the scientific community to better understand the pathophysiology of obesity. This epidemic is all the more concerning given the clear association between excess adiposity and adverse health consequences such as cardiovascular disease (CVD) and type 2 diabetes mellitus (T2DM). The risks associated with overweight/obesity are primarily related to the deposition of adipose tissue, which leads to excess adiposity or body fatness. Furthermore, weight loss, specifically loss of body fat, is associated with improvement in obesity-related comorbidities. Before weight loss interventions can be recommended, however, patients must be assessed for their adiposity-related risk. Unfortunately, healthcare providers and systems have not done a good job of assessing for excess adiposity even in its simplest form, such as measuring body mass index (BMI). It is for these reasons that we must emphasize the importance of assessing adiposity in clinical practices. Although it can be argued that the entire population should be targeted as an important public health issue with a goal of prevention of weight gain and obesity, there are currently so many “at risk” individuals that simple strategies to identify and treat those individuals are necessary. We must identify those individuals at highest risk of comorbidities in order to identify those who might benefit the most from aggressive weight management.

This scientific statement will first briefly review the epidemiology of obesity and its related comorbidities, supporting the need for improved assessment of adiposity in daily clinical practice. This will be followed by a discussion of some of the challenges and issues associated with assessing adiposity and then by a review …

Assessing Adiposity A Scientific Statement From the American Heart Association

Cardiovascular diseases and their associated risk factors remain the main cause of mortality in western societies. In order to assess the prevalence of cardiovascular risk factors (CVRFs) in the Caucasian population of Lausanne, Switzerland, we conducted a population-based study (Colaus Study). A secondary aim of the CoLaus study will be to determine new genetic determinants associated with CVRFs. Single-center, cross-sectional study including a random sample of 6,188 extensively phenotyped Caucasian subjects (3,251 women and 2,937 men) aged 35 to 75 years living in Lausanne, and genotyped using the 500 K Affymetrix chip technology. Obesity (body mass index ≥ 30 kg/m2), smoking, hypertension (blood pressure ≥ 140/90 mmHg and/or treatment), dyslipidemia (high LDL-cholesterol and/or low HDL-cholesterol and/or high triglyceride levels) and diabetes (fasting plasma glucose ≥ 7 mmol/l and/or treatment) were present in 947 (15.7%), 1673 (27.0%), 2268 (36.7%), 2113 (34.2%) and 407 (6.6%) of the participants, respectively, and the prevalence was higher in men than in women. In both genders, the prevalence of obesity, hypertension and diabetes increased with age. The prevalence of major CVRFs is high in the Lausanne population in particular in men. We anticipate that given its size, the depth of the phenotypic analysis and the availability of dense genome-wide genetic data, the CoLaus Study will be a unique resource to investigate not only the epidemiology of isolated, or aggregated CVRFs like the metabolic syndrome, but can also serve as a discovery set, as well as replication set, to identify novel genes associated with these conditions.

https://link.springer.com/content/pdf/10.1186%2F1471-2261-8-6.pdf

The CoLaus study: a population-based study to investigate the epidemiology and genetic determinants of cardiovascular risk factors and metabolic syndrome.

Summary Objective: To compare body composition determined by bioelectrical impedance (BIA) consumer devices against criterion estimates determined by whole body magnetic resonance imaging (MRI) and dual energy X-ray absorptiometry (DXA) in healthy normal weight, overweight and obese adults. Methods: In 106 adults (54 females, 52 males, age 54.2 ± 16.1 years, BMI 25.8 ± 4.4 kg/m2 ) fat mass (FM), skeletal muscle mass (SM), total body bone-free lean mass (TBBLM), and level of visceral fat mass (VF) were estimated by 3 single-frequency bipedal (foot-to-foot) and one tretra polar BIA device, and compared to body composition measured by MRI and DXA. Bland-Altman and simple linear regression analyses were used to determine agreement between methods. Results: %FM DXA, SMMRI or TBBLMDXA showed good relative and absolute agreement with two bipolar and one tetrapolar instrument (r 2 = 0.92–0.96; all p < 0.001; mean bias <1.5 %FM and <1 kg SM or TBBLM) and less relative and absolute agreement for another bipolar device (r 2 = 0.82 and 0.84, mean bias ~3 %FM and ~3 kg SM). The 95% limits of agreement (bias ± 2 SD) were narrowest for the tetrapolar device (–6.59 to 4.61 %FM and –4.62 to 4.74 kg SM) and widest for bipolar instruments (up to –14.54 to 8.58 %FM and –9.52 to 3.92 kg SM). Systematic biases for %FM were found for all bipedal devices, but not for the tetrapolar instrument. Conclusion: Because of the lower agreement between foot-to-foot BIA and DXA or MRI for the assessment of body composition in individuals, tetrapolar electrode arrangement should be preferred for individual or public use. Bipolar devices provide accurate results for field studies with group estimation.

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Accuracy of bioelectrical impedance consumer devices for measurement of body composition in comparison to whole body magnetic resonance imaging and dual X-ray absorptiometry.

Intermittent energy restriction may result in greater improvements in insulin sensitivity and weight control than daily energy restriction (DER). We tested two intermittent energy and carbohydrate restriction (IECR) regimens, including one which allowed ad libitum protein and fat (IECR+PF). Overweight women (n 115) aged 20 and 69 years with a family history of breast cancer were randomised to an overall 25 % energy restriction, either as an IECR (2500-2717 kJ/d, < 40 g carbohydrate/d for 2 d/week) or a 25 % DER (approximately 6000 kJ/d for 7 d/week) or an IECR+PF for a 3-month weight-loss period and 1 month of weight maintenance (IECR or IECR+PF for 1 d/week). Insulin resistance reduced with the IECR diets (mean - 0·34 (95% CI - 0·66, - 0·02) units) and the IECR+PF diet (mean - 0·38 (95% CI - 0·75, - 0·01) units). Reductions with the IECR diets were significantly greater compared with the DER diet (mean 0·2 (95% CI - 0·19, 0·66) μU/unit, P= 0·02). Both IECR groups had greater reductions in body fat compared with the DER group (IECR: mean - 3·7 (95% CI - 2·5, - 4·9) kg, P= 0·007; IECR+PF: mean - 3·7 (95% CI - 2·8, - 4·7) kg, P= 0·019; DER: mean - 2·0 (95% CI - 1·0, 3·0) kg). During the weight maintenance phase, 1 d of IECR or IECR+PF per week maintained the reductions in insulin resistance and weight. In the short term, IECR is superior to DER with respect to improved insulin sensitivity and body fat reduction. Longer-term studies into the safety and effectiveness of IECR diets are warranted.

/pdf/the-effect-of-intermittent-energy-and-carbohydrate-c073jc7dth.pdf

The effect of intermittent energy and carbohydrate restriction v. daily energy restriction on weight loss and metabolic disease risk markers in overweight women

To investigate changes in body composition and the validity of the leg-to-leg bioimpedance (LTL) method to measure body fat during active weight loss (WL) and weight regain (WR). Longitudinal, 12-week weight loss intervention (3.3–3.8 MJ/day) and subsequent follow-up at 1 year. Fifty-eight adult women aged between 24 and 65 years (mean age: 46.8±8.9 years) and with a body mass index (BMI) ⩾25 kg/m2 (mean BMI: 31.6±2.5 kg/m2, range=26.0–48.2 kg/m2) participated in the study. Fat mass (FM) was measured at baseline, 12 weeks, 24 weeks and 52 weeks using three- and four-compartment (4-C) models, air displacement plethysmography (ADP), deuterium dilution – total body water (TBW), dual-energy X-ray absorptiometry (DXA), skinfold thickness (SFT), tetrapolar bioelectrical impedance analysis (T-BIA) and LTL. At the end of the weight loss programme, subjects lost 9.9±3.5 kg weight (P<0.001) and 7.6±0.5 kg fat (P<0.001) but after 1 year they had regained 4.9±3.7 kg of weight and 3.7±2.9 kg of fat. The 4-C model showed that FM and TBW accounted for 76.2 and 23.6% of the loss in body mass and 81.8 and 17.7% of the tissue accrued during weight regain, respectively. The estimate of body fat change by LTL relative to multi-compartment models (WLbias±2s.d.=0.51±3.26 kg; WRbias±2s.d.=−0.25±2.30 kg) was similar to ADP, DXA and TBW in both phases but it was better than T-BIA (WLbias±2s.d.=0.17±7.90 kg; WRbias±2s.d.=−0.29±7.59 kg) and skinfold thickness (WLbias±2s.d.=2.68±6.68 kg; WRbias±2s.d.=−0.84±3.80 kg). Weight loss and regain were associated with minimal changes in lean tissue as measured using multi-compartment models. The LTL system is a useful method to measure body composition changes during clinical weight management programmes.

https://tanita.eu/media/wysiwyg/research-pdf/validity_of_bioimpedance_to_estimate_changes_in_body_fat_during_weight_loss.pdf

Validity of the leg-to-leg bioimpedance to estimate changes in body fat during weight loss and regain in overweight women: a comparison with multi-compartment models

Background: Current guidelines for obesity management emphasize the improvements in health risks associated with weight losses of 5-10% initial weight. However, most of the data is derived from periods of acute weight loss and may not represent the true effect in the longer term or in obese but otherwise healthy individuals. This study examines the temporal changes in risk factors for cardiovascular disease with weight change over 5 2 weeks.

S. Evans

Papers

Validity of the leg-to-leg bioimpedance to estimate changes in body fat during weight loss and regain in overweight women: a comparison with multi-compartment models

Changes in risk factors for cardiovascular disease with body fat loss in obese women