Monounsaturated fat-rich diet reduces body adiposity in women with obesity, but does not influence energy expenditure and substrate oxidation: a parallel randomized controlled clinical trial.

BACKGROUND: Obesity is an important and growing health problem whose treatment involves dietary changes. In this context, studying the role of macronutrients in weight loss is required in order to understand which strategies may be applied for weight loss. We aimed to evaluate the effects of diets rich in polyunsaturated (PUFAs) and monounsaturated fatty acids (MUFAs) on resting energy expenditure (REE), substrate oxidation, and weight loss in women with obesity. METHODS: Randomized, controlled, single blind, parallel-group clinical trial was conducted for 60 days. Participants (n = 32) were divided into three groups: G1= normocaloric PUFAs-rich diet (12% of total energy expenditure (TEE), 10% of n-6 and up to 2% of n-3); G2= normocaloric MUFAs-rich diet (15-20% TEE); and G3= maintenance of the usual diet. Anthropometric and metabolic variables (REE and substrate oxidation by indirect calorimetry) were evaluated. RESULTS: G2 decreased body weight (-1.92 ± 1.99 kg, P = 0.02), body mass index (BMI) (-0.69 ± 0.70 kg/m2; P = 0.02), waist circumference (WC) (-1.91 ± 1.82 cm; P = 0.02), and body fat (-1.14 ± 1.53 kg; P = 0.04). CONCLUSION: MUFAs-rich diet reduces body weight, BMI, body fat, and WC. CLINICAL TRIALS: NCT02656940. CLINICAL TRIAL REGISTRATION: Clinical Trials: NCT02656940.

Influence of the unsaturated fatty acids on body weight, glucose, and lipids metabolism in obese women with Pro12Pro genotype in PPARY2 gene / Influencia de los ácidos grasos insaturados en el peso corporal y en el metabolismo de la glucosa y de los lípidos en mujeres obesas con el genotipo Pro12Pro en el gen PPARY2

Background: The type of dietary fatty acid may have different effects on obesity and its complications, however, these effects can be influenced by genes and polymorphisms, such as peroxisome proliferator-activated receptor γ isoform 2 (PPARγ2). Moreover, it is unclear whether the degree of unsaturation of the fat has different effects on lipid and glucose metabolism, and particularly the loss of body weight. Objective: To evaluate the influence of diets rich in polyunsaturated fatty acids (PUFA) and monounsaturated fatty acids (MUFA) on anthropometric and biochemical variables in obese woman with genotype Pro12Pro on PPARγ2 gene on body weight, glycemic and lipemic profile. Methods: Eighteen obese women with Pro12Pro genotype in PPARγ2 gene were randomized into groups to receive a high PUFAs (PUFA-diet, n = 8) or MUFAs (MUFA-diet, n = 10) diets. Anthropometrics (body mass index [BMI] and waist circumference) and biochemical variables (glucose, insulin, HOMA-IR, total cholesterol, LDL-cholesterol, and HDL-cholesterol and triglycerides) were evaluated at baseline and after 45 days. Results: Anthropometric and biochemical variables were similar between groups at baseline and after intervention (p > 0.05). BMI decrease only in PUFA-diet (p = 0.01), probably due to the lower lipid content in this diet. MUFA-diet decrease fasting glucose (p = 0.03), insulin (p = 0.03), and HOMA-IR (p = 0.02). Conclusion: Compared to PUFA, MUFA was more efficient to reduce the insulin resistance in obese women with Pro12Pro genotype in PPARγ2, even in high saturated fatty acids and total fat diet (AU)

Introducción: el tipo de ácido graso de la dieta presenta diferentes efectos sobre la obesidad y sus complicaciones, pero estos efectos pueden verse influenciados por los genes y sus polimorfismos, tales como los receptores activados por el proliferador de los peroxisomas isoforma γ2 (PPARγ2). Además, no está claro si el grado de insaturación de los lípidos posee diferentes efectos en el metabolismo de los lípidos y de la glucosa y, particularmente, en la pérdida de peso. Objetivos: evaluar la influencia de dietas ricas en ácidos grasos poliinsaturados (AGPI) y monoinsaturados (AGMI) en las variables antropométricas y bioquímicas en el peso corporal y el perfil glucémico y lipémico en mujeres obesas con el genotipo Pro12Pro en el gen PPARγ2. Métodos: dieciocho mujeres obesas con genotipo Pro12Pro fueron distribuidas aleatoriamente para una de las dietas, rica en AGPI (n = 8) o AGMI (n = 10). Las variables antropométricas (índice de masa corporal [IMC] y circunferencia de la cintura) y bioquímicas (glucosa, insulina, HOMA-IR, colesterol total, LDL-colesterol, HDL-colesterol y triglicéridos) fueron evaluadas antes y después de un periodo de 45 días. Resultados: las variables antropométricas y bioquímicas fueron similares entre los grupos antes y después de la intervención (p > 0,05). El IMC disminuyó después de la ingesta de AGPI (p = 0,01), probablemente debido al menor contenido de lípidos. El AGMI redujo la glucosa (p = 0,03), insulina (p = 0,03) y HOMA-IR (p = 0,02). Conclusión: los AGMI fueron más eficientes para reducir la resistencia a la insulina en mujeres obesas con el genotipo Pro12Pro en el gen PPARγ2, aunque las mujeres presentaran una elevada ingesta de lípidos totales y ácidos grasos saturados (AU)