Full-fat Dairy Products, Body Weight Control and Metabolic Health

The overall objective is to examine the long-term effects of full-fat dairy products on appetite and body weight control, diet quality, and metabolic health in adults living with obesity (18-55 y) and in children (8-16 y). This project also aims to identify some key mechanisms (i.e. gut peptides, gut microbiota) involved in the beneficial impact of dairy products on these outcomes. This study aims to evaluate the impact of a web-based nutrition intervention integrating full-fat or low-fat dairy products into the diets of families (at least one parent with BMI \>30 kg/m2) under free-living conditions, on overall dairy consumption, body weight and composition, diet quality, eating and psychobehavioural traits and cardiometabolic outcomes, in normal weight/obese adults and children. This is a randomized, controlled, single-blind study consisting of three parallel groups. Families (n=25/group) will be randomized to either an intervention promoting either 1) low-fat or 2) full-fat dairy) or 3) control group (no intervention but same follow-up) over an 8-week period. The nutrition intervention aims to increase the quantity and variety of dairy products (i.e. low and full-fat milk, yogurt and cheese) in the diet. Evaluation periods for each family will be conducted before the study (week 0 in the lab), at the end (week 9 at home) and after 3 months (week 20 at home) after the intervention. Measurements include anthropometry, fasting lipid and glycemic profiles, diet quality, eating and psychobehavioral traits and food reward/appreciation/acceptance. The proposed research will provide timely data required to support recommendations to consume low and full-fat dairy products in individuals living with obesity, particularly during weight loss and maintenance. It will also provide the basis for family interventions that have the potential to positively impact diet quality and dairy consumption.