Effects of n-3 Intake on Lipid Profile, Biochemical and Inflammatory Markers in Subjects With Obesity

Overview

Obesity is a chronic disease characterized by the excessive accumulation of adipose tissue that is harmful to health. Dietary habits modification through a caloric restriction, macronutrient distribution including linoleic and linolenic (n-6:n-3) polyunsaturated fatty acids (PUFAs) ratio, has been suggested for obesity management. It has been proposed that the optimal n-6: n-3 ratio should be between 1:1 and 5:1 to maintain a healthy balance. Purpose: Compare the effect of a diet n6:n3 ratio of polyunsaturated fatty acids with a group supplemented with n-3 PUFA on lipid profile in erythrocyte membrane, biochemical and inflammatory markers in subjects with obesity. Methods: 58 subjects were randomly divided into two groups: fish oil group and the placebo group. Anthropometric and biochemical data were evaluated, cytokine levels was performed using the Bio-PlexPro™ HumanTh17Cytokine Assays (MagPix) panel. The fatty acid profile quantification in the erythrocyte membrane was carried out by gas chromatography. Statistical analysis was performed with Statistical Package for the Social Sciences (SPSS) v.22 software.

A randomized clinical trial was conducted at the Institute of Translational Nutrigenetics and Nutrigenomics of the University of Guadalajara. All participants were recruited through flyers and social media invitations. Sample size was determined according to the mean difference formula for clinical trials. To achieve a statistical power of 80% and an alpha of 5%, a sample size of 19 participants in each study group was required. However, 58 obese individuals who met the selection criteria were randomized in n-3 group or placebo group. Blood sample, height and weight were measured after 8-12 hour fast and wearing light clothes. The nutritional intervention consisted in 20% reduction by the total estimated energy through the Mifflin-St.Jeor formula was calculated, following a 50% to carbohydrates, 20% to proteins and 30% to lipids distribution. All participants received a balanced nutritional plan of omega-6/omega-3 close to 5:1 ratio, according to estimated energy. Additionally, a high omega-3 foods list was proportioned to emphasize their consumption during the study. Fish oil group besides the diet was supplemented with omega 3, the dosage was 2 capsules per day, containing 1.5 g of total omega 3, of which 1000 mg were EPA and 500mg DHA. The omega 3 capsules were obtained from the same batch, and a toxicity analysis was performed to verify the safety or the placebo group (2 capsules per day made from sunflower oil). This study was approved by the Ethics and Biosafety Committee of the Health Sciences Center, University of Guadalajara (Registration number CI-01219) and was carried out according to the Declaration of Helsinki (2013) and all the participants signed a written consent-informed.