Grant: Project Grant

Obesity is associated with several risk factors (for example, high blood sugar, poor insulin response and inflammation) that increase the risk of developing cardiovascular disease and type 2 diabetes (T2DM). Obesity is also associated with abnormalities in the immune system and an increased risk of infection. Specific components of the diet such as high dietary intake of fat and sugar influence not only the development of obesity but also the immune system. Therefore, it is still unclear if the immune dysfunction associated with obesity in human are attributable to 1- the excess of body fat per se and/or 2- the metabolic complications also often associated with obesity such as elevated blood glucose and/or 3- the overall poor diet quality of an individual. We are proposing a study where we will characterize, in controlled feeding conditions, the functionality of the immune system by investigating a panel of makers of the immune system (inflammation in the blood and the response of immune cells). At the end of a 4-week feeding period where participants will all consume the same standardized diet, we will compare the immune system of three groups of adults with obesity: a. obesity with normal blood glucose concentrations; b. obesity with marginally elevated blood glucose concentrations; and c. obesity with T2DM. All groups will be matched for age, sex and body mass index, and compared to a group of healthy normal weight subjects. By comparing these four groups, we will be able to gain an understanding of the immune complications associated with obesity alone (e.g. excess of body fat per se) and the association of blood sugar and diet in modulating these immune complications. This is essential to subsequently identify dietary interventions to counteract the immune dysfunctions associated with obesity.