Carey's research focus is on obesity and diabetes, trying to understand how our diet, exercise, and exposure to environmental chemicals negatively impact adipose tissue metabolism, which, in turn, can increase the risk of developing obesity and diabetes. Animals and humans are subjects for her work. Animal work has used the miniature Yucatan swine, and most recently the Sprague-Dawley rat to examine the metabolic and biochemical alterations in adipose tissue metabolism after exposure to lipid-soluble flame retardants chemicals. Human work documents the appearance of these same flame retardants in breast milk, while also demonstrating the rapid transfer of conjugated linoleic acid, a "healthy fat" in milk of cows fed on pasture, from the mother's diet to her breast milk. Her current working hypothesis is that environmental chemicals may be a third component (after diet and exercise) that contribute to the obesity/diabetes epidemic.