title: Prognostic implications for insulin-sensitive and insulin-resistant normal-weight and obese individuals from a population-based cohort. Two Healthy Diets Modulate Gut Microbial Community Improving Insulin Sensitivity in a Human Obese Population.
abstract: BACKGROUND There are few prospect i ve data on the prognosis of insulin-sensitive and insulin-resistant normal-weight ( NW ) or obese individuals . OBJECTIVES The estimated liver fat content , incidences of hyperglycemia and cardiovascular disease , and all-cause and cardiovascular mortality rates were investigated in a population -based cohort of 1658 individuals who were categorized according to BMI and insulin resistance as defined by HOMA-IR values ≥2.5 and the presence of metabolic syndrome . DESIGN This was a prospect i ve cohort study with a 9-y follow-up . Anthropometric values , blood pressure , and blood metabolic variables were measured , and information on vital status was collected from demographic files at follow-up . RESULTS A total of 137 of 677 NW individuals ( 20 % ) were classified as insulin resistant and normal weight ( IR-NW ) , and 72 of 330 obese individuals ( 22 % ) were classified as insulin sensitive and obese ( IS-obese ) . Incidences of diabetes , impaired fasting glucose , and cardiovascular events were 0.4 % , 6.3 % , and 3.3 % , respectively , in insulin-sensitive and normal-weight ( IS-NW ) individuals ( reference category ) ; 5.8 % , 10.2 % , and 6.6 % , respectively , in IR-NW individuals ; and 5.6 % , 8.3 % , and 8.3 % , respectively , in IS-obese individuals . In a multiple logistic regression model , risks of incident hyperglycemia and cardiovascular events increased in both groups compared with in the reference category [ HR ( 95 % CI ) : 2.54 ( 1.42 , 4.55 ) and 1.98 ( 0.86 , 4.54 ) in IR-NW subjects ; 2.16 ( 1.01 , 4.63 ) and 2.76 ( 1.05 , 7.28 ) in IS-obese subjects ] . The estimated liver fat content significantly increased during follow-up only in the IR-NW group in the same model . Cardiovascular mortality was 2 - 3-fold higher in IR-NW and IS-obese than in IS-NW individuals in a Cox regression model . CONCLUSIONS Our data refute the existence of healthy obese phenotypes because IS-obese individuals  showed increased cardiometabolic risk . The existence of unhealthy NW phenotypes is supported by their increased risk of incident hyperglycemia , fatty liver , cardiovascular events , and death CONTEXT Gut microbiota , which acts collectively as a fully integrated organ in the host metabolism , can be shaped by long-term dietary interventions after a specific diet . OBJECTIVE The aim was to study the changes in microbiota after 1 year 's consumption of a Mediterranean diet ( Med diet ) or a low-fat , high-complex carbohydrate diet ( LFHCC diet ) in an obese population . DESIGN Participants were r and omized to receive the Med diet ( 35 % fat , 22 % monounsaturated ) and the LFHCC diet ( 28 % fat , 12 % monounsaturated ) . SETTING AND PARTICIPANTS The study was conducted in 20 obese patients ( men ) within the Coronary Diet Intervention With Olive Oil and Cardiovascular Prevention ( CORDIOPREV ) study , an ongoing prospect i ve , r and omized , opened , controlled trial in patients with coronary heart disease . MAIN OUTCOME MEASURE We evaluated the bacterial composition and its relationship with the whole fecal and plasma metabolome . RESULTS The LFHCC diet increased the Prevotella and decreased the Roseburia genera , whereas the Med diet decreased the Prevotella and increased the Roseburia and Oscillospira genera ( P = .028 , .002 , and .016 , respectively ) . The abundance of Parabacteroides distasonis ( P = .025 ) and Faecalibacterium prausnitzii ( P = .020 ) increased after long-term consumption of the Med diet and the LFHCC diet , respectively . The changes in the abundance of 7 of 572 metabolites found in feces , including mainly amino acid , peptide , and sphingolipid metabolism , could be linked to the changes in the gut microbiota . CONCLUSIONS Our results suggest that long-term consumption of the Med and LFHCC diets exerts a protective effect on the development of type 2 diabetes by different specific changes in the gut microbiota , increasing the abundance of the Roseburia genus and F. prausnitzii , respectively
target: The baseline characteristics related to lipid profile were more favorable for metabolically healthy obese than for metabolically unhealthy obese .
  Changes in fasting glucose , HOMA-IR and hsCRP did not show significant changes .
  Sufficient evidence was not found to support the use of specific diets in metabolically healthy obese subjects .
  This analysis suggests that the effect of caloric restriction exerts its effects through a reduction in BMI , blood pressure and triglycerides in metabolically healthy obese ( MHO ) patients
background: The aim of this systematic review was to assess the effect of diet on changes in parameters describing the body size phenotype of metabolically healthy obese subjects .