Of all the emails I receive, the most common question asked is, “How can I reduce my (fill in the blank with a given body part).” Whether it’s the belly, thighs, butt or any other problem area, my answer is always the same: Sorry, but you can’t spot reduce!
Simply stated, there is no way to dictate what area of your body you lose fat from. It’s a physiologic impossibility. All the sit-ups in the world won’t give you a flat stomach; no amount of lower body exercises will directly diminish the size of your thighs. In reality, trying to eradicate your problem areas with targeted movements is literally an exercise in futility.
A recent study conducted by Redman et al. (2007) demonstrated the senselessness of trying to spot reduce. Thirty-five overweight subjects were placed into one of three random groups: a control group who ate their normal diet; an energy restricted group who reduced calories by 25%; or an energy restriction plus exercise group who reduced calories by 12.5% and increased energy expenditure through exercise by 12.5%. After six months, results showed that although fat depots were reduced by approximately 30% in men and 25% in women in both the calorie restricted and the calorie restricted plus exercise groups, the distribution of the fat depots were reduced equally throughout the whole body. This study used both dual energy X-ray absorptiometry (DEXA) and multi-slice computed tomograpy (CT) to evaluate fat mass, adding to the validity of results.
In order to appreciate why spot reduction doesn’t work, it is necessary to understand how fat is synthesized. When calories are consumed in abundance, your body converts the excess nutrients into fat-based compounds called triglycerides, which are then stored in cells called adipocytes. Adipocytes are pliable storehouses that either shrink or expand to accommodate fatty deposits. They are present in virtually every part of the body. There is a direct correlation between the size of adipocytes and obesity: the larger your adipocytes, the fatter you appear.
When you exercise, triglycerides are broken back down into fatty acids, which are then transported via the blood to be used in target tissues for energy. Because fatty acids must travel through the circulatory system—a time-consuming event—it is just as efficient for your body to utilize fat from one area as it is another. In other words, the proximity of fat cells to the working muscles is completely irrelevant from an energy standpoint. Since the body can’t preferentially use fat from a particular area, it simply draws from adipocytes in all regions of the body including the face, trunk and extremities.
Bottom line: When you exercise, fat will be burned globally throughout your body. Some areas will be more sensitive to fat loss than others, but over time you will lean out even the most stubborn problem areas provided you stay regimented with your exercise routine and maintain a caloric deficit.
Redman LM, Heilbronn LK, Martin CK, Alfonso A, Smith SR, Ravussin E; Pennington CALERIE Team. Effect of calorie restriction with or without exercise on body composition and fat distribution. J Clin Endocrinol Metab. 2007 Mar;92(3):865-72