Americans love eating in cafeterias. Nothing is more fun than sampling the vast and sundry mixture of tasty delights full of fat, salt and sugar. In response, our brain always rewards us with a dopamine-fueled euphoria. Unfortunately, whatever goes up must come down; that includes our mood. The meal is finished and we can almost sense the deposition of fat molecules into the fats cells nestled around our waist. We are suddenly grateful that the exit doors of cafeterias are always a few inches wider than their entry doors. It's time for a few cups of coffee!
Coffee contains many healthy chemicals such as potassium, niacin, magnesium, and a variety of antioxidants (I've written about many of these in previous blogs). One of the problems in documenting the benefits of coffee drinking in humans is that we have complex diets. Coffee drinkers are often also smokers; in addition, they consume more calories, eat less fruit and have a more sedentary lifestyle than people who drink tea. Drinking coffee does lower uric acid levels in the blood, which is a risk factor for cardiovascular disease, and reduces the risk of type 2 diabetes and some cancers; however, it does matter how your coffee is prepared. Non-filtered, boiled coffee, in contrast to filtered coffee, actually increases serum levels of the bad cholesterol LDL without affecting blood levels of the good cholesterol HDL. Thus, it appears as though the constituents of coffee may alter the way we metabolize and distribute our fat. Does this translate into a removal of fat from around the waist? A recent study from a group of scientists at the University of Southern Queensland in Toowoomba Australia attempted to answer this question.
When obese diabetic rats were given caffeine for thirty weeks their ability to regulate blood sugar and insulin levels improved, unfortunately, the level of cholesterol in their blood increased significantly. Rats placed on cafeteria-style diets that are high in carbohydrates and fat developed symptoms of the now infamous metabolic syndrome that is characterized by obesity, hypertension, impaired glucose tolerance, cardiovascular damage, and fatty liver and elevated blood lipids. Daily coffee intake (equal to about five cups of regular brewed coffee per day) significantly benefited these rats by improving the health of their cardiovascular system, lowered blood pressure, and improved liver function and glucose tolerance. The contractility of their heart muscle improved in a way that resembled the hypertrophy often seen in athletes where the heart actually becomes more efficient.
The problem was that abdominal obesity (i.e. belly fat) and elevated triglyceride levels were completely unaffected. The authors concluded that this pattern of changes may explain why coffee drinking does not affect obesity. Coffee drinking has many health benefits; reducing belly fat is not one of them.
© Gary L. Wenk, Ph.D. Author of Your Brain on Food (Oxford Univ Press)
See also: "Why Marijuana and Coffee are good for the brain"