Clinical trials

The goal of this study is to understand if there are differences in the fat, muscle and metabolism of individuals who developed obesity during childhood versus those who developed obesity in adulthood. We will do this by having recruited participants undergo subcutaneous adipose tissue biopsies in the abdomen and thigh, a muscle biopsy in the thigh, collect blood and urine samples, a DEXA scan and 3 submaximal exercise tests. participants will also have their resting energy expenditure measured through indirect calorimetry to tailor a targeted weight loss protocol through caloric restriction and cardiovascular exercise (3 times a week). After 10% of weight loss is completed, study participants will repeat all tests during a 2 week weight stabilization period. At 12 weeks into the intervention, indirect calorimetry, DEXA scan and blood tests will be repeated.

Current recommendations for protein intake after bariatric surgery are not based on strong scientific evidence. It remains unclear how much protein should be eaten to minimize muscle loss and preserve the metabolism and function of individuals post-bariatric surgery. The objective of this study is to analyze the relationships between changes in body composition, nutrition and protein intake, and muscle function after bariatric surgery to further our understanding of the nutritional needs of patients after bariatric surgery. We intend to recruit around 75 participants, men and women, aged between 18 and 65 years. Participants will be recruited from the Bariatric Surgery Clinic, McGill University Health Center.

Fat tissue in different parts of the body has different characteristics. Several studies have associated abdominal fat to an increased risk for multiple metabolic diseases, such as type 2 diabetes and cardiovascular disease, compared with fat located under the skin at the hips and thighs. However, the investigators do not know how the abdominal fat causes or contributes to the development of these diseases or how the development of these disease may in turn cause or contribute to changes in the fat tissue. The general objective of this study is to understand these mechanisms. To investigate these questions, the study will recruit 140 participants, both men and women aged 18-65 years. The participants will be divided into three groups: 40 people with obesity, 40 with diabetes, and 60 lean individuals. Participants will be recruited from patients at the CIUSSS du Nord-de-l'Île-de Montréal - Hôpital du Sacré-Coeur de Montréal who are awaiting bariatric or general abdominal surgery, as well as from the general population in the Montreal area.