Fat Metabolism and Weight Regain
By Cynthia K. Buffington, PhD
Weight loss causes changes in fat metabolism that can eventually result in weight regain. Investigators placed a radioactive tag on dietary fat and followed it through the human body. They discovered that weight loss reduces the amount of fat the body burns (oxidizes) for energy and increases the amount of fat that is stored in fat storage depots (adipose tissue). Other studies also show that fat storage depots following dietary or surgical weight loss have an increased capacity to accumulate fat. Because of these changes in fat metabolism, a greater proportion of calories consumed will be stored as fat, contributing to weight regain. However, there are certain measures that can be taken to help counteract adverse changes in fat metabolism. These include:
- Perform moderate activity daily. Regular moderate activity, such as walking, hiking, swimming, cycling, or dancing, increase fat oxidation in muscle, the primary site of fat oxidation in the body. At the same time, regular moderate activity enhances the breakdown of fat in fat storage depots.
- Reduce sitting time. Studies are now finding that sitting for long periods daily (at your desk, on the computer, or watching TV) can actually offset many of the benefits of exercising for 30 minutes to an hour per day. This is because sitting causes metabolic changes that a) reduce fat uptake into muscle and, thereby, reduce fat oxidation, and b) cause hormonal changes that increase fat accumulation in fat storage depots. Reduction of sitting time and frequent interruptions in sitting, if only for short periods, at work and at home are extremely important to help prevent these metabolic conditions associated with prolonged sitting.
- Increase the intake of foods that cause your body to burn or oxidize more fat and reduce fat accumulation in storage depots. These include: a) green and oolong teas, b) foods high in omega 3 essential fatty acids (fatty fish, flax, mustard, grape and pumpkin seeds, walnuts, cabbage, cauliflower, and cloves), c) low-fat dairy and other foods rich in calcium (broccoli and greens, sardines, shrimp, oysters, dairy alternatives, orange juice with calcium, more ), quality protein (eggs, dairy, fish, chicken, turkey, beef, pork, quinoa, soybeans, and more), and foods high in fiber, vitamins and minerals (fruits, vegetables, whole grains, nuts, seeds, legumes).
- Reduce foods that cause hormonal and metabolic changes in the body that increase fat storage and accumulation (reduce processed meats and grains, foods high in sugar and high fructose corn syrup, foods containing or cooked in trans or partially hydrogenated fat).
- Be diligent in taking vitamin and mineral supplements. Studies find that vitamin and mineral repletion (not having deficiencies) can increase fat oxidation and energy expenditure and cause weight reduction or favorable changes in body composition even in the absence of calorie restriction.