America’s sweet tooth was the driving force behind a nearly 40 percent increase in per capita sugar consumption between 1959 and 2000. At the turn of the century, the average U.S. citizen was eating over 150 pounds of sugar annually. Even though this upward trend in sugar consumption has tapered somewhat, added sugars still account for about 15 percent of your total daily caloric intake. It isn’t clear if caffeine -- a widely used appetite suppressant -- can subdue your sugar cravings, but it may have undesirable effects on your overall sugar metabolism.
According to a June 2010 review in “Yale Journal of Biology and Medicine,” your nervous system is essentially wired to crave sugar. And it isn’t just garden-variety table sugar that keeps you yearning for more. By stimulating your taste buds and, subsequently, the appetite centers in your brain, even noncaloric “artificial” sweeteners can heighten your sugar cravings. By suppressing your appetite, caffeine may alleviate sugar cravings to some degree, but you may pay a large metabolic price for this small benefit.
Multiple clinical trials have shown that caffeine triggers a surge in pancreatic insulin secretion. Insulin stimulates the cells in your liver, muscles and fat tissue to absorb glucose, and insulin levels normally increase after you eat. However, a study published in the July 2004 issue of “The American Journal of Clinical Nutrition” suggested that caffeine induces a state of insulin resistance in your cells, which prompts your pancreas to produce even more insulin than it typically would in response to a meal. Insulin resistance can be particularly troublesome for diabetics or overweight individuals.
Cortisol is a hormone produced by your adrenal glands in response to stress. It is also secreted as a “counter-regulatory” hormone whenever insulin levels rise, which helps to blunt the glucose-lowering effects of insulin. In April 2011, scientists at Harokopio University in Athens, Greece, showed that men who drank a regular cup of caffeinated coffee exhibited sustained elevations in their serum cortisol levels. Elevated cortisol levels are associated with increased appetite, weight gain and insulin resistance. Cortisol’s specific effects on sugar cravings have not been defined.
Caffeine is commonly used in weight-loss supplements as a means to suppress your appetite and increase your metabolic rate. However, research demonstrates that caffeine may exert metabolic effects that thwart many dieters’ efforts. Its usefulness for reducing sugar cravings is unclear. Interestingly, caffeinated coffee does not cause some of the same physiologic responses that pure caffeine does, perhaps because coffee contains substances that counteract some of caffeine’s undesirable effects. Ask your doctor or nutritionist if caffeine is appropriate for you.