Obesity and type 2 diabetes mellitus (T2DM) are complex chronic diseases with rapidly growing prevalence across the world. Human studies have found that both genetic and environmental factors contribute to T2DM; the clearest lifestyle factors are high caloric intake and low physical activity. The mechanisms by which human T2DM arises is still unclear, but obesity, insulin resistance and ß-cell dysfunction all play a role.

Rodents on a high-fat diet are often used to study human T2DM. As a result, many of the mechanisms of rodent T2DM are known. Translation of the research, however, to human obesity and diabetes is still not possible.

This review evaluates the limits of rodent high-fat diet models of human T2DM. Modifying the diet of rodents appears to have limited applicability to human diabetes for several reasons, including: very different dietary compositions, variability in bacterial species and strains in the gut, and inconsistency of the penetrance, severity, and duration of T2DM.

Authors say the time has come to turn away from rodents and seek to understand human obesity and diabetes by using data specific to humans. They say this would increase our understanding of disease mechanisms and spur the development of new therapeutics.

Review:

Lai M, et al. (2014) You are what you eat, or are you? The challenges of translating high-fat-fed rodents to human obesity and diabetes. Nutrition & Diabetes doi:10.1038/nutd.2014.30