Purpose of Review
We review the underlying mechanisms and potential benefits of intermittent fasting (IF) from animal models and recent clinical trials.
Recent Findings
Numerous variations of IF ...exist, and study protocols vary greatly in their interpretations of this weight loss trend. Most human IF studies result in minimal weight loss and marginal improvements in metabolic biomarkers, though outcomes vary. Some animal models have found that IF reduces oxidative stress, improves cognition, and delays aging. Additionally, IF has anti-inflammatory effects, promotes autophagy, and benefits the gut microbiome. The benefit-to-harm ratio varies by model, IF protocol, age at initiation, and duration.
Summary
We provide an integrated perspective on potential benefits of IF as well as key areas for future investigation. In clinical trials, caloric restriction and IF result in similar degrees of weight loss and improvement in insulin sensitivity. Although these data suggest that IF may be a promising weight loss method, IF trials have been of moderate sample size and limited duration. More rigorous research is needed.
Obesity and its many serious comorbidities exert a heavy toll in both human and economic terms. More than one-third of adults in the United States are obese and, therefore, subject to elevated rates ...of diabetes, hypertension, dyslipidemia, and other cardiovascular disease risk factors. The negative effect on the quality of life (QoL) of these individuals is enormous. Among the severely obese, QoL scores are comparable to QoL scores associated with diabetes and laryngeal cancer. The medical costs of obesity-related illnesses in the United States have been estimated at $209.7 billion annually (in 2008 dollars). For example, with regard to impact on pharmaceutical costs, obesity is associated with a more than 13-fold increase in the cost of antidiabetic medications. The cost of absenteeism to employers has been estimated to exceed $4.3 billion annually. Successful and cost-effective short-term treatments for obesity are available, and have been shown to reduce cardiovascular risk factors. Intensive lifestyle intervention with the goal of losing 7% of baseline body weight, for example, resulted in a 58% reduction in the risk of diabetes in patients with prediabetes. In clinical trials, improvements in other cardiovascular risk factors, such as elevated triglycerides and high blood pressure, have also been seen with a modest weight loss of 5% to 10% of baseline body weight. As obesity becomes an ever greater public health problem, additional interventions with long-term efficacy are needed to reduce body weight and maintain weight loss.
Abstract
Context
Weight regain (WR) after bariatric surgery is emerging as a common clinical problem due to the increase in the number of procedures performed. Early interventions are necessary to ...curtail the potential recurrence of comorbid conditions. However, it is often difficult to recognize WR early enough to introduce mitigating measures because there are no current guidelines for timely diagnosis and assessment of the severity of this condition.
Objective
We present a practical approach for the early recognition of WR, based on 11-year follow-up data from our multiethnic bariatric surgery patient population.
Methods
We classify WR according to the rate of increase in weight relative to nadir weight, normalized per 30-day interval. We also review pertinent literature about the etiologic factors contributing to WR after bariatric surgery.
Results
According to our algorithm, mild, moderate, and rapid WR are defined as weight increases of 0.2% to <0.5%, 0.5% to 1.0%, and more than 1.0% of nadir weight per 30 days, respectively. Treatment options, including dietary counseling, use of antiobesity medication, and consideration of surgical revision, are described. A case is presented to illustrate the utility of timely identification of WR and the importance of collaboration between bariatric surgeons, obesity medicine specialists, and dietitians.
Conclusion
Our approach emphasizes the importance of regular long-term follow-up for all bariatric surgery patients.
To determine the association between vitamin D status and morbidity and mortality in adult hospitalized coronavirus disease 2019 (COVID-19) patients METHODS: We performed a retrospective chart review ...study in COVID-19 patients aged ≥18 year hospitalized at Boston University Medical Center between March 1 and August 4, 2020. All studied patients tested positive for COVID-19 and had serum levels of 25-hydroxyvitamin D (25OHD) results measured within 1 year prior to the date of positive tests. Medical information was retrieved from the electronic medical record and was analyzed to determine the association between vitamin D status and hospital morbidity and mortality.
Among the 287 patients, 100 (36%) were vitamin D sufficient (25OHD >30 ng/mL) and 41 (14%) died during hospitalization. Multivariate analysis in patients aged ≥65 years revealed that vitamin D sufficiency (25OHD ≥30 ng/mL) was statistically significantly associated with decreased odds of death (adjusted OR 0.33, 95% CI, 0.12-0.94), acute respiratory distress syndrome (adjusted OR 0.22, 95% CI, 0.05-0.96), and severe sepsis/septic shock (adjusted OR 0.26, 95% CI, 0.08-0.88), after adjustment for potential confounders. Among patients with body mass index <30 kg/m
, vitamin D sufficiency was statistically significantly associated with a decreased odds of death (adjusted OR 0.18, 95% CI, 0.04-0.84). No significant association was found in the subgroups of patients aged <65 years or with body mass index ≥30 kg/m
.
We revealed an independent association between vitamin D sufficiency defined by serum 25(OH)D ≥30 ng/mL and decreased risk of mortality from COVID-19 in elderly patients and patients without obesity.
An appropriate balance between proinflammatory (Th17 and Th1) and anti-inflammatory (regulatory T cells Tregs and Th2) subsets of T cells is critical to maintain homeostasis and avoid inflammatory ...disease. Type 2 diabetes (T2D) is a chronic inflammatory disease promoted by changes in immune cell function. Recent work indicates T cells are important mediators of inflammation in a mouse model of T2D. These studies identified an elevation in the Th17 and Th1 subsets with a decrease in the Treg subset, which culminates in inflammation and insulin resistance. Based on these data, we tested the hypothesis that T cells in T2D patients are skewed toward proinflammatory subsets. Our data show that blood from T2D patients has increased circulating Th17 cells and elevated activation of Th17 signature genes. Importantly, T cells required culture with monocytes to maintain Th17 signatures, and fresh ex vivo T cells from T2D patients appeared to be poised for IL-17 production. T cells from T2D patients also have increased production of IFN-γ, but produce healthy levels of IL-4. In contrast, T2D patients had decreased percentages of CD4(+) Tregs. These data indicate that T cells in T2D patients are naturally skewed toward proinflammatory subsets that likely promote chronic inflammation in T2D through elevated cytokine production. Potential therapies targeted toward resetting this balance need to be approached with caution due to the reciprocal relationship between Th17 cells and Tregs. Understanding the unique aspects of T2D T cells is essential to predict outcomes of such treatments.
Obesity causes serious medical complications and impairs quality of life. Moreover, in older persons, obesity can exacerbate the age-related decline in physical function and lead to frailty. However, ...appropriate treatment for obesity in older persons is controversial because of the reduction in relative health risks associated with increasing body mass index and the concern that weight loss could have potential harmful effects in the older population. This joint position statement from the American Society for Nutrition and the NAASO, The Obesity Society reviews the clinical issues related to obesity in older persons and provides health professionals with appropriate weight-management guidelines for obese older patients. The current data show that weight-loss therapy improves physical function, quality of life, and the medical complications associated with obesity in older persons. Therefore, weight-loss therapy that minimizes muscle and bone losses is recommended for older persons who are obese and who have functional impairments or medical complications that can benefit from weight loss.
Abstract Objective High fat, low carbohydrate (HFLC) diets have become popular tools for weight management. We sought to determine the effects of a HFLC diet compared to a low fat high carbohydrate ...(LFHC) diet on the change in weight loss, cardiovascular risk factors and inflammation in subjects with obesity. Methods Obese subjects (29.0–44.6 kg/m2 ) recruited from Boston Medical Center were randomized to a hypocaloric LFHC (n = 26) or HFLC (n = 29) diet for 12 weeks. Results The age range of subjects was 21–62 years. As a percentage of daily calories, the HFLC group consumed 33.5% protein, 56.0% fat and 9.6% carbohydrate and the LFHC group consumed 22.0% protein, 25.0% fat and 55.7% carbohydrate. The change in percent body weight, lean and fat mass, blood pressure, flow mediated dilation, hip:waist ratio, hemoglobin A1C, fasting insulin and glucose, and glucose and insulin response to a 2 h oral glucose tolerance test did not differ (P > 0.05) between diets after 12 weeks. The HFLC group had greater mean decreases in serum triglyceride (P = 0.07), and hs-CRP (P = 0.03), and greater mean increases in HDL cholesterol (P = 0.004), and total adiponectin (P = 0.045) relative to the LFHC. Secreted adipose tissue adiponectin or TNF- α did not differ after weight loss for either diet. Conclusions Relative to the LFHC group, the HFLC group had greater improvements in blood lipids and systemic inflammation with similar changes in body weight and composition. This small-scale study suggests that HFLC diets may be more beneficial to cardiovascular health and inflammation in free-living obese adults compared to LFHC diets.
Medium chain triglycerides (MCT) have unique metabolic properties which may improve insulin sensitivity (Si) and beta cell function but data in humans are limited. We conducted a 6-week clinical ...trial of MCT oil supplementation.
22 subjects without diabetes (8 males, 14 females, mean ± standard error age 39±2.9 years, baseline BMI 27.0±1.4 kg/m2) were counseled to maintain their body weight and physical activity (PA) during the trial. Dietary intake, PA data, body composition, and resting energy expenditure (REE) were obtained through dietary recall, international PA questionnaire, dual x-ray absorptiometry, and indirect calorimetry, respectively. MCT prescriptions were given based on REE and PA to replace part of dietary fat with 30 grams of MCT per 2000 kcal daily. Insulin-modified frequently sampled intravenous glucose tolerance tests were performed before and after MCT to measure changes in Si, acute insulin response (AIR), disposition index (DI), and glucose effectiveness (Sg).
MCT were well tolerated and weight remained stable (mean change 0.3 kg, p = 0.39). Fasting REE, respiratory quotient, and body composition were stable during the intervention. There were no significant changes in mean fasting glucose, insulin, insulin resistance, fasting total ketones, Si, AIR, DI, Sg, leptin, fructosamine, and proinsulin. The mean change in Si was 0.5 10-4 min-1 per mU/L (95% CI: -1.4, 2.4), corresponding to a 12% increase from baseline, and the range was -4.7 to 12.9 10-4 min-1 per mU/L. Mean total adiponectin decreased significantly from 22925 ng/mL at baseline to 17598 ng/mL at final visit (p = 0.02). The baseline clinical and laboratory parameters were not significantly associated with the change in Si.
There were a wide range of changes in the minimal model parameters of glucose and insulin metabolism in subjects following 6 weeks of MCT as an isocaloric substitution for part of usual dietary fat intake. Since this was a single-arm non-randomized study without a control group, it cannot be certain whether these changes were due to MCT so further randomized controlled trials are warranted.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
...the cause of obesity has as much to do with the human reaction to overfeeding as it does the production of foods that are being overfed. Interestingly, the 10 most abundantly consumed foods in the ...United States include the mainly highly processed foods listed here. * Grain-based desserts (cakes, cookies, donuts, pies, crisps, cobblers, and granola bars) * Yeast breads * Chicken and chicken-mixed dishes * Soda, energy drinks, and sports drinks * Pizza * Alcoholic beverages * Pasta and pasta dishes * Mexican mixed dishes * Beef and beef-mixed dishes * Dairy desserts The list clearly excludes all fruits and vegetables in their native state while including very few protein-containing nutrients. The overproduction and overconsumption that accompany obesity also increase the release of greenhouse gases that exacerbate global warming, increase the risk of catastrophic weather events, and reduce crop yields and the micronutrient content of crops, thereby leading to food insecurity and undernutrition, particularly in low- and middle-income countries. Potential solutions to the obesity pandemic are beyond the purview of medical practice and the scope of what the public health community can accomplish. ...the likelihood of behavioral or public health policy interventions greatly impacting this disease in the next 10 to 15 years is small.
The prevalence of obesity has been increasing worldwide over the past 30 years and is a major public health concern. Obesity is known to be associated with metabolic disturbances including insulin ...resistance and inflammation; however, there is a subset of obese subjects who have normal metabolic profiles, and they have been identified as the metabolically healthy obese (MHO). Several studies have described MHO as obese individuals who have high levels of insulin sensitivity and the absence of diabetes, dyslipidemia, or hypertension. The prevalence of MHO varies from 20 to 30 % among obese individuals. This review will discuss the MHO phenotype; the differences between MHO and metabolically unhealthy obese (MUO) individuals; and the possible underlying mechanisms including adipocyte differentiation, immune regulation, and cellular energy metabolism.
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