Tomato (Solanum lycopersicum L.) and type 2 diabetes

Since the late 1990s, various basic studies and clinical research have linked tomato to type 2 diabetes. This link, however, has yet to be understood and summarized. The present review systematically summarizes the effect of tomato on type 2 diabetes. The PubMed, Web of Science, and Embase databases were searched for reports published (in the English language) from December 1999 to August 2017 using the keywords tomato and diabetes. Relevant references from particular publications were also considered. To date, studies in humans have not shown a significant relationship between tomato and the risk of type 2 diabetes, whereas mainstream in vivo system studies have generally shown that tomato or its bioactive compounds may have an antihyperglycemic effect. Nevertheless, tomato (fresh or cooked) has been found to be favorable for diabetic conditions because it decreases diabetes-induced oxidative stress, inflammation, accelerated atherosclerosis, and tissue (i.e., retinal, renal, and musculoskeletal) damage. Further studies in humans are very important toward elucidating the hypoglycemic response of tomato or its derived compounds in diabetic conditions.