If you are one of the more than one-third of Americans who are overweight, you may be tempted to eat mainly low-fat foods or foods that contain artificial sweeteners in an effort to lose weight. However, these very foods may actually contribute to weight gain if you aren't careful.
Eating too many carbohydrates, especially refined carbohydrates, may lead to weight gain. A high-carbohydrate diet can cause large increases and then drops in blood sugar levels, says Dr. Walter Willett, the chair of the nutrition department at Harvard School of Public Health. Low blood sugar causes you to get hungry again, which could lead to overeating. Eating sweets and processed foods, most of which are made with refined grains, makes you more likely to gain weight, while eating whole grains makes weight gain less likely, according to an article published in "The New England Journal of Medicine" in June 2011.
Although there are some healthful options available at fast foods restaurants, most of the options are fat and calorie bombs. Not all studies involving fast food consumption and weight gain conclude that fast food causes weight gain, but a November 2008 review article in "Obesity Reviews" found that the majority of the 16 studies reviewed showed an association between fast food consumption and an increase in total calories consumed and weight gain.
Foods Containing Artificial Sweeteners
While you might be tempted to swap out a regular soda for a diet soda to save calories, this might not be the best idea. A study published in "Obesity" in August 2008 found that people who drank artificially sweetened beverages or used artificial sweeteners in foods were actually more likely to gain weight than those who didn't use these sweeteners, although there isn't enough evidence yet to say for sure that artificial sweeteners cause weight gain. This might be due to the fact that people often overcompensate for the saved calories by eating more later, or because the sweet taste increases hunger and cravings for other foods since your body associates a sweet taste with calories.
Foods High in Saturated Fat
It probably isn't a big surprise that foods high in saturated fat can cause weight gain. These foods have more calories per gram, so it is easy to eat too much of them and gain weight. Unsaturated fats, which mainly come from plant foods, may be less likely to cause weight gain than animal-based fats, most of which are saturated fats, even though they contain the same amount of calories per gram, according to a study published in "Obesity" in April 2007. Participants who increased their intake of saturated fat experienced weight gain, while those who increased the amount of unsaturated fats they consumed didn't gain weight.
Foods Containing Trans Fat
Although most people don't consume a large amount of trans fat, foods containing even a small amount of this fat could increase your chances of weight gain, especially if you are already overweight. The April 2007 article in "Obesity" noted that every 1 percent increase in calories from trans fat led to a weight gain of about 2.3 pounds in the overweight women who participated in the study.
If you really want to avoid weight gain, stick to beverages like water and tea that are naturally free of calories. Avoid sugar-sweetened beverages like regular soda and fruit drinks, since drinking these makes it more likely you will gain weight and become obese, according to a review article published in "The American Journal of Clinical Nutrition" in August 2006.
- Frontline: Did the Low-fat Era Make Us Fat?
- New England Journal of Medicine: Changes in Diet and Lifestyle and Long-Term Weight Gain in Women and Men
- Obesity: Fueling the Obesity Epidemic? Artificially Sweetened Beverage Use and Long-term Weight Gain
- Obesity: Dietary Fat and Weight Gain Among Women in the Nurses’ Health Study
- Obesity Reviews: Fast Food Consumption and Increased Caloric Intake: A Systematic Review of a Trajectory Towards Weight Gain and Obesity Risk
Based in Massachusetts, Jessica Bruso has been writing since 2008. She holds a master of science degree in food policy and applied nutrition and a bachelor of arts degree in international relations, both from Tufts University.