Fat chance for cinnamon in fight against obesity

An encouraging bit of news has emerged in the fight against obesity. New research from the University of Michigan (U-M) Life Sciences Institute has determined how cinnamon might be enlisted in the battle of the bulge.Scientists had earlier observed that cinnamaldehyde, an essential oil that gives cinnamon its flavour, appeared to protect mice against obesity and hyperglycemia. But the mechanisms underlying the effect were not well understood. Researchers in the lab of Jun Wu, research assistant professor at the LSI, wanted to better understand cinnamaldehyde’s action and determine whether it might be protective in humans, too.Their findings, which appear in the December issue of the journal Metabolism, indicated that cinnamaldehyde improves metabolic health by acting directly on fat cells, or adipocytes, inducing them to start burning energy through a process called thermogenesis.Cinnamaldehyde is the organic compound that gives cinnamon its flavour and odour. It makes up about half of cinnamon oil and is used to flavour chewing gum, ice cream, candy and beverages, as well as perfumes. Cinnamaldehyde is also used as a natural fungicide and an insecticide.Wu and her colleagues tested human adipocytes from volunteers representing a range of ages, ethnicities and body mass indices. Adipocytes normally store energy in the form of lipids. When the cells were treated with cinnamaldehyde, the researchers noticed increased expression of several genes and enzymes that enhance lipid metabolism. They also observed an increase in Ucp1 and Fgf21, which are important metabolic regulatory proteins involved in thermogenesis.As the researchers explained in a companion article in Michigan News, the storing of fat in the adipocytes was useful to our ancestors who had less access to high-fat foods and therefore a greater need to store fat in the body for winter or food scarcities. With the rising obesity epidemic, researchers like Wu have been looking for ways to prompt fat cells to activate thermogenesis, turning those fat-burning processes back on.Wu, who also is an assistant professor of molecular and integrative physiology at the U-M Medical School, believes that cinnamaldehyde may offer one such activation method. And because it is already used widely in the food industry, it might be easier to convince patients to stick to a cinnamon-based treatment than to a traditional drug regimen. “Cinnamon has been part of our diets for thousands of years, and people generally enjoy it,” Wu said. “So if it can help protect against obesity, too, it may offer an approach to metabolic health that is easier for patients to adhere to.”Wu cautioned that further study is needed to determine how best to harness cinnamaldehyde’s metabolic benefits without causing adverse side effects. She says cinnamaldehyde could be a natural trigger for this fat burning process in lieu of traditional drug regimens. Wu also says more study needs to be done about the benefits and side effects before people start using the Cinnamon Challenge to lose weight. The research was supported by the Human Frontier Science Programme, Edward Mallinckrodt Jr. Foundation, National Institutes of Health and American Heart Association.