Dietary Fatty Acid Composition and Obesity-related Metabolic Abnormalities

Individuals have a significant capacity to adapt to different environments by changing their
core metabolic pathways. This adaptation is especially important in regards to diet.
Epidemiological research over the last several decades have shown that diets high in
saturated fats have a greater ability to cause insulin resistance and the 'metabolic
syndrome' while diets low in saturated fats (or a so called 'Mediterranean Diet), reduces the
risk for cardiovascular disease. In humans, experimental diets high in unsaturated fats, as
compared to high carbohydrate or high saturated fat diets, result in increased insulin
sensitivity and improved lipid profiles.

In this application, the investigators propose to systematically assess the effects of two
diets enriched in either saturated or unsaturated fatty acids and determine the cellular and
molecular mechanisms of the apparent increase in insulin sensitivity. The investigators
hypothesize that individuals will 'adapt' to the different diets and the investigators will
be able to generate predictive alterations in gene expression and metabolites that underlie
the alterations in metabolism. In parallel, the investigators will test the ability of these
different diets to affect the release of gastrointestinal hormones that may be critical to
modulation of appetite.