Lifestyle factors and visceral adipose tissue: Results from the PREDIMED-PLUS study.
PloS one. 2019;14(1):e0210726
Plain language summary
Excess visceral adipose tissue (VAT, abdominal fat) is a risk factor for developing cardiovascular disease, type 2 diabetes mellitus and all cause mortality. Lifestyle factors, including diet and physical activity, are associated with VAT. This cross-sectional study evaluated the association between different levels of physical activity (PA), adherence to an energy-restricted Mediterranean diet and sedentary lifestyle with VAT in older people with overweight/obesity and metabolic syndrome. Data were taken from an ongoing randomised study evaluating the effect of a weight loss programme based on an energy-restricted Mediterranean diet, promotion of physical activity and behavioural support compared to usual care consisting of advice on an energy-unrestricted Mediterranean diet only. Total and moderate-to-vigorous physical activity and muscle strength were inversely, and sedentary behaviour was positively associated with VAT. There was no statistically significant association between VAT and light exercise, adherence to the energy-reduced Mediterranean diet and watching TV.
BACKGROUND Visceral adipose tissue (VAT) is a strong predictor of cardiometabolic health, and lifestyle factors may have a positive influence on VAT depot. This study aimed to assess the cross-sectional associations between baseline levels of physical activity (PA), sedentary behaviours (SB) and adherence to the Mediterranean diet (MedDiet) with VAT depot in older individuals with overweight/obesity and metabolic syndrome. METHODS Baseline data of the PREDIMED-Plus study including a sample of 1,231 Caucasian men and women aged 55-75 years were used. Levels of leisure-time PA (total, light, and moderate-to-vigorous, in METs·min/day) and SB (total and TV-viewing, in h/day) were evaluated using validated questionnaires. Adherence to the MedDiet was evaluated using a 17-item energy-restricted MedDiet (erMedDiet) screener. The chair-stand test was used to estimate the muscle strength. VAT depot was assessed with DXA-CoreScan. Multivariable adjusted linear regression models were used to evaluate the association between lifestyle factors and VAT. For the statistics we had used multiadjusted linear regression models. RESULTS Total leisure-time PA (100 METs·min/day: β -24.3g, -36.7;-11.9g), moderate-to-vigorous PA (β -27.8g, 95% CI -40.8;-14.8g), chair-stand test (repeat: β -11.5g, 95% CI -20.1;-2.93g) were inversely associated, and total SB (h/day: β 38.2g, 95% CI 14.7;61.7) positively associated with VAT. Light PA, TV-viewing time and adherence to an erMedDiet were not significantly associated with VAT. CONCLUSIONS In older adults with overweigh/obesity and metabolic syndrome, greater PA, muscle strength, and lower total SB were associated with less VAT depot. In this study, adherence to an erMedDiet was not associated with lower VAT.
A structured weight loss program increases gut microbiota phylogenetic diversity and reduces levels of Collinsella in obese type 2 diabetics: A pilot study.
PloS one. 2019;14(7):e0219489
Plain language summary
The global obesity epidemic is a major cause of the increase in type 2 diabetes mellitus (T2DM) and ensuing cardiovascular disease. The causes of obesity are complex ,and it has been shown that changes in the microbiome are associated with obesity. The microbiome can be altered through dietary intervention and weight loss. The aim of this open label pilot study was to investigate the microbiome of obese patients with T2DM during a weight loss programme. During the first six weeks the diet consisted of formula drink providing 800kcal per day, followed by nine weeks during which a regular diet of 1,200-1,500kcal per day was reintroduced, depending on the individuals’ needs. All participants lost weight continuously over the 15 weeks, from an average BMI of 39.6 at the start to 33.1 at the end of the programme. This was accompanied with an improvement in glucose metabolism, total and LDL cholesterol and uric acid levels, but not HDL cholesterol or triglycerides. All participants experienced changes in their microbiome towards greater diversity after the first six weeks of the low-calorie formula diet but these changes were partially reversed at the end of the study period at 15 weeks. A particular type of bacteria, Collinsella, which has been associated with poor metabolic health, was the only type found to remain reduced at the end of the 15 weeks, an 8.4-fold decrease. The authors hypothesise that this reduction in Collinsella may be associated with the improvement of metabolic factor in these patients at the end of the study.
The global obesity epidemic constitutes a major cause of morbidity and mortality challenging public health care systems worldwide. Thus, a better understanding of its pathophysiology and the development of novel therapeutic options are urgently needed. Recently, alterations of the intestinal microbiome in the obese have been discussed as a promoting factor in the pathophysiology of obesity and as a contributing factor to related diseases such as type 2 diabetes and metabolic syndrome. The present pilot study investigated the effect of a structured weight loss program on fecal microbiota in obese type 2 diabetics. Twelve study subjects received a low-calorie formula diet for six weeks, followed by a nine week food reintroduction and stabilization period. Fecal microbiota were determined by 16S rRNA gene sequencing of stool samples at baseline, after six weeks and at the end of the study after fifteen weeks. All study subjects lost weight continuously throughout the program. Changes in fecal microbiota were most pronounced after six weeks of low-calorie formula diet, but reverted partially until the end of the study. However, the gut microbiota phylogenetic diversity increased persistently. The abundance of Collinsella, which has previously been associated with atherosclerosis, decreased significantly during the weight loss program. This study underlines the impact of dietary changes on the intestinal microbiome and further demonstrates the beneficial effects of weight loss on gut microbiota. Trial registration: ClinicalTrials.gov NCT02970838.
A 12-Month Lifestyle Intervention Program Improves Body Composition and Reduces the Prevalence of Prediabetes in Obese Patients.
Obesity facts. 2018;11(5):393-399
Plain language summary
Obesity and its impact on the prevalence of diabetes and subsequent cardiovascular disease is one of the major health burdens in Western societies. Lifestyle intervention studies have shown that weight loss combined with increased physical activity can improve metabolic risk factors. The aim of this study was to evaluate the effect of a comprehensive lifestyle intervention programme on weight and metabolic risk factors in 5884 obese individuals. The programme included 61 sessions over 12 months, including 41 exercise sessions, 12 psychological/self-management sessions and 8 nutritional counselling sessions (based on a low glycaemic index, low fat diet). After 12 months there was a significant reduction in weight (average 6%), waist circumference, physical fitness and all metabolic parameters (including blood sugar and fat metabolism). Overall, in 839 (38%) of the 2,227 participants who were pre-diabetic before intervention, the criteria of pre-diabetes were no longer detectable after 12 months, whilst only 66 (3%) progressed to type 2 diabetes mellitus. 46.7% of the 1,641 participants fulfilling the criteria of metabolic syndrome before the intervention, did not show any signs of this syndrome after the intervention; whilst only 120 participants (+7.3%) newly developed metabolic syndrome. The authors concluded that the intensive lifestyle intervention programme was successful, even in obese people with pre-diabetes.
BACKGROUND The present study investigated the effects of a 12-month interdisciplinary standardized lifestyle program addressing physical activity and changes in dietary and lifestyle behavior in 2,227 obese prediabetic participants. METHODS Measures of obesity (BMI, waist circumference), cardiopulmonary fitness, and metabolic parameters were determined before and after the intervention period. RESULTS From the 2,227 participants who were initially prediabetic, 839 participants (-37.7%) did no longer show the criteria of prediabetes after the intervention and had normal HbA1c levels. CONCLUSION The clinical effects are substantial, and it is likely that the applied intense and multidisciplinary lifestyle interventions could reduce the risk of developing diabetes and the prevalence of a full-blown metabolic syndrome in obese and prediabetic patients.
Regaining body weight after weight reduction further increases pulse wave velocity in obese men with metabolic syndrome.
Plain language summary
Atherosclerosis can increase stiffness of the aorta and, therefore, increased pulse wave velocity (PWV), which is a predictor for cardiovascular disease and mortality. Metabolic syndrome (MetS), diabetes and obesity increase the risk of aortic stiffness and higher PWV. Weight loss may reduce arterial stiffness but mechanisms are not known. The aim this study was to investigate changes over time of PWV, ankle-brachial index (ABI, a marker for arterial disease of the leg), insulin resistance and inflammatory markers after weight loss and regained weight in obese non-diabetic men with MetS compared to lean controls. Obese participants followed a three months weight loss programme based on diet and exercise during which they lost an average of 8.6kg and saw statistically significant improvements in blood pressure and many biochemical markers but not in PWV or ABI. At the second follow-up visit, at 60 months, they had regained their weight, blood pressure and most biochemical markers were back to baseline whilst PWV and adiponectin were worse than before weight loss. Increases in blood pressure but not weight, hs-CRP (an inflammatory marker) or insulin resistance correlated with the increase in PWV after weight regain. Although healthy controls also gained weight over the 60 months study duration, their increase in PWV was significantly lower than in obese participants. Their PWV was also lower at baseline.
Subjects with metabolic syndrome (MetS) or obesity have worse arterial stiffness. However, there have been no studies addressing time-sequential changes in pulse wave velocity (PWV) after weight loss and then regaining weight in obese non-diabetic men with MetS.We prospectively enrolled 40 obese, non-diabetic men with MetS undergoing a 3-month weight reduction program. Another 26 lean and healthy men were recruited for comparisons. Oral glucose tolerance test and brachial ankle (ba) PWV were assessed in study subjects. Eighteen obese non-diabetic MetS and 15 lean control subjects had follow-ups at the 60th month.The body weight of obese MetS decreased from 94.8 ± 7.6 to 86.1 ± 9.0 (N = 18, P < .001) after a 3-month weight reduction program but regained gradually thereafter to 93.6 ± 11.6 kg at the 60th month (P < .001 versus 3rd month). baPWV decreased after weight loss slightly (P = .240) while weight regain significantly increased the baPWV (from 3rd month, 1358 ± 168 to 60th month 1539 ± 264 cm/sec, P < .001). Systolic and diastolic blood pressure increments correlated with the increment of baPWV after weight regain. At the 60th month, lean controls (N = 15) had increases in body weight while their baPWV increased non-significantly. The increments of baPWV after weight regain in obese MetS were significantly higher than the increment of baPWV in lean controls after weight gain.In conclusion, regaining body weight after weight reduction worsened arterial stiffness with significant increase of baPWV in obese non-diabetic MetS.
A Pecan-Rich Diet Improves Cardiometabolic Risk Factors in Overweight and Obese Adults: A Randomized Controlled Trial.
Plain language summary
There has been a global rise in cardiovascular disease (CVD) and type 2 diabetes mellitus (TD2M) and dietary risk factors are a known contributor. While evidence has shown that an increased intake of tree nuts is associated with a reduced risk of disease indicators, there is limited research specifically on the effects of pecans. The aim of this randomised crossover trial was to assess the impact of pecan consumption on biomarkers related to CVD and T2DM risk in 26 overweight or obese women. Participants consumed a pecan-rich diet with an iso-caloric control diet of similar fat and fibre content, but absent in nuts, for four weeks with a two-week washout period. This trial demonstrated that displacing a portion of saturated fat in the typical American diet with pecans has a protective effect for CVD and TD2M. Based on these results, the authors recommend using dietary change as a first-line approach to disease prevention and management and suggest further studies be done to better understand potential benefits and associated mechanisms.
Evidence from observational and intervention studies has shown a high intake of tree nuts is associated with a reduced risk of cardiovascular disease (CVD), mortality from type 2 diabetes (T2DM), and all-cause mortality. However, there is limited data regarding their effects on indicators of cardiometabolic risk other than hypercholesterolemia, and little is known about the demonstrable health benefits of pecans (Carya illinoensis (Wangenh.) K.Koch). We conducted a randomized, controlled feeding trial to compare the effects of a pecan-rich diet with an isocaloric control diet similar in total fat and fiber content, but absent nuts, on biomarkers related to CVD and T2DM risk in healthy middle-aged and older adults who are overweight or obese with central adiposity. After 4 weeks on a pecan-rich diet, changes in serum insulin, insulin resistance (HOMA-IR) and beta cell function (HOMA-β) were significantly greater than after the control diet (p < 0.05). Pecan consumption also lowered the risk of cardiometabolic disease as indicated by a composite score reflecting changes in clinically relevant markers. Thus, compared to the control diet, the pecan intervention had a concurrent and clinically significant effect on several relevant markers of cardiometabolic risk.