Twelve-Month Outcomes after Metabolic and Bariatric Surgery among Youths Participating in a Structured Preparation and Follow-Up Program: Results of the Youth with Extreme Obesity Study.

INTRODUCTION: While invasive and associated with risks, metabolic and bariatric surgery (MBS) can promote sustained weight loss and substantial health benefits in youths with extreme obesity. The path toward informed decision making for or against MBS is poorly characterized and postoperative follow-up to assess risks and benefits is inconsistent. In youths with extreme obesity, we aimed to evaluate decision making toward MBS, as well as MBS outcomes and adherence with follow-up and recommendations in the setting of a structured pre- and post-MBS program. METHODS: Participants were recruited in the setting of the multicenter "Youth with Extreme Obesity Study" (YES). YES is a cohort study in adolescents and young adults aged 14-24 years with obesity (BMI ≥30.0 kg/m2) who were recruited at four medical centers and one job center in Germany between 2012 and 2018. Participants at two medical centers with BMI ≥35 kg/m2, aged 14-24 years, and interested in pursuing MBS were included in the subproject 3 "Safety and effectiveness of weight loss surgery in adolescents with severe obesity within a structured pre- and post-surgery treatment program - an observational study" that comprised a 2-months pre- and 12-months post-MBS program. RESULTS: Twenty-eight of 169 youths (17%) with BMI ≥35 kg/m2 were interested in MBS. Twenty-six fulfilled published eligibility criteria for MBS and participated in the structured pre-MBS preparation program. Of these, 9 participants (2 females) decided against, and 17 (n = 11 females) decided for MBS (sleeve gastrectomy). The 12-month follow-up rate was high (16/17 [94%]) and all participants achieved significant weight reduction (ΔBMI: -16.1 ± 5.6 kg/m2). Eleven of 16 participants (69%) reported taking the prescribed dietary supplements in the first year after MBS, but only five of them (31%) did so daily. In contrast to the high 12-month retention rate, follow-up after completion of the structured program was low at 24-months (9/16 [56%]) and at 36-months (5/15 [36%]), respectively. CONCLUSION: Participants demonstrated active decision making for or against MBS and high adherence with the structured pre- and 12 months post-MBS program, but participation was low thereafter. These findings endorse the need for longer term structured post-MBS programs to capture long-term outcomes and provide adequate care in this vulnerable group at the transition to adulthood.

Behavioral Characteristics and Self-Reported Health Status among 2029 Adults Consuming a "Carnivore Diet".

BACKGROUND: The "carnivore diet," based on animal foods and excluding most or all plant foods, has attracted recent popular attention. However, little is known about the health effects and tolerability of this diet, and concerns for nutrient deficiencies and cardiovascular disease risk have been raised. OBJECTIVES: We obtained descriptive data on the nutritional practices and health status of a large group of carnivore diet consumers. METHODS: A social media survey was conducted 30 March-24 June, 2020 among adults self-identifying as consuming a carnivore diet for ≥6 mo. Survey questions interrogated motivation, dietary intake patterns, symptoms suggestive of nutritional deficiencies or other adverse effects, satisfaction, prior and current health conditions, anthropometrics, and laboratory data. RESULTS: A total of 2029 respondents (median age: 44 y, 67% male) reported consuming a carnivore diet for 14 mo (IQR: 9-20 mo), motivated primarily by health reasons (93%). Red meat consumption was reported as daily or more often by 85%. Under 10% reported consuming vegetables, fruits, or grains more often than monthly, and 37% denied vitamin supplement use. Prevalence of adverse symptoms was low (<1% to 5.5%). Symptoms included gastrointestinal (3.1%-5.5%), muscular (0.3%-4.0%), and dermatologic (0.1%-1.9%). Participants reported high levels of satisfaction and improvements in overall health (95%), well-being (66%-91%), various medical conditions (48%-98%), and median [IQR] BMI (in kg/m2) (from 27.2 [23.5-31.9] to 24.3 [22.1-27.0]). Among a subset reporting current lipids, LDL-cholesterol was markedly elevated (172 mg/dL), whereas HDL-cholesterol (68 mg/dL) and triglycerides (68 mg/dL) were optimal. Participants with diabetes reported benefits including reductions in median [IQR] BMI (4.3 [1.4-7.2]), glycated hemoglobin (0.4% [0%-1.7%]), and diabetes medication use (84%-100%). CONCLUSIONS: Contrary to common expectations, adults consuming a carnivore diet experienced few adverse effects and instead reported health benefits and high satisfaction. Cardiovascular disease risk factors were variably affected. The generalizability of these findings and the long-term effects of this dietary pattern require further study.

Diets Varying in Carbohydrate Content Differentially Alter Brain Activity in Homeostatic and Reward Regions in Adults.

BACKGROUND: Obesity has one of the highest refractory rates of all chronic diseases, in part because weight loss induced by calorie restriction, the first-line treatment for obesity, elicits biological adaptations that promote weight regain. Although acute feeding trials suggest a role for macronutrient composition in modifying brain activity related to hunger and satiety, relevance of these findings to weight-loss maintenance has not been studied. OBJECTIVES: We investigated effects of weight-loss maintenance diets varying in macronutrient content on regional cerebral blood flow (rCBF) in brain regions involved in hunger and reward. METHODS: In conjunction with a randomized controlled feeding trial, we investigated the effects of weight-loss maintenance diets varying in carbohydrate content [high, 60% of total energy: n = 20; 6 men/14 women; mean age: 32.5 y; mean BMI (in kg/m 2): 27.4; moderate, 40% of total energy: n = 22; 10 men/12 women; mean age: 32.5 y; mean BMI: 29.0; low, 20% of total energy: n = 28; 12 men/16 women; mean age: 33.2 y; mean BMI: 27.7] on rCBF in brain regions involved in hunger and reward preprandial and 4 h postprandial after 14-20 wk on the diets. The primary outcome was rCBF in the nucleus accumbens (NAcc) at 4 h postprandial; the secondary outcome was preprandial rCBF in the hypothalamus. RESULTS: Consistent with a priori hypothesis, at 4 h postprandial, NAcc rCBF was 43% higher in adults assigned to the high- compared with low-carbohydrate diet {P[family-wise error (FWE)-corrected] < 0.05}. Preprandial hypothalamus rCBF was 41% higher on high-carbohydrate diet [P(FWE-corrected) < 0.001]. Exploratory analyses revealed that elevated rCBF on high-carbohydrate diet was not specific to prandial state: preprandial NAcc rCBF [P(FWE-corrected) < 0.001] and 4 h postprandial rCBF in hypothalamus [P(FWE-corrected) < 0.001]. Insulin secretion predicted differential postprandial activation of the NAcc by diet. CONCLUSIONS: We report significant differences in rCBF in adults assigned to diets varying in carbohydrate content for several months, which appear to be partially associated with insulin secretion. These findings suggest that chronic intake of a high-carbohydrate diet may affect brain reward and homeostatic activity in ways that could impede weight-loss maintenance. This trial was registered at clinicaltrials.gov as NCT02300857.