The Effects of the Food Preservative Propionic Acid in Post-prandial Metabolism

Propionic acid (PA) is used as a preservative in foods such as cheeses, baked goods, or additive for artificial fruit flavors. The U.S. Environmental Protection Agency considers it safe and therefore, has no limitation on its use. Since PA has been shown before to serve as a substrate for glucose production in the liver, the purpose of this study is to find out if PA intake causes changes in levels of glucose, insulin and other important hormones following a meal. This research study will compare PA to placebo. The placebo looks exactly like the active substance, but it does not contain any active agent (PA). Placebos are used in research studies to see if the results are due to the study drug or to other reasons. The investigators plan to have 20 subjects take part in this study at the Brigham and Women's Hospital (BWH).