A long-held belief in the health and fitness industry is that to lose weight, you simply need to burn more calories than you consume through food. Over time, accumulating this caloric deficit, either through restricting the food you eat or increasing your daily exercise, would result in weight-loss. A recent study, conducted by nutrition experts at Harvard University, reached some conclusions that may counter this supposedly tried-and-true method for shedding pounds.
The Harvard Study
The study, brought to my attention by a June, 2011 article in The New York Times by health writer Jane Brody, investigated the long-term effects of a variety of lifestyle factors, dietary habits and physical fitness patterns on weight. The researchers collected data on over 120,000 individuals over a 20-year period and found that certain foods were more highly related to weight-loss/weight-gain than others. Potato chips led the list of foods that contributed most highly to weight-gain, followed by potatoes, sweetened beverages and red meat. Foods that correlated with weight-loss included fruits and vegetables, nuts and yogurt. For an abstract of the study, refer to this article.
Exploring The Findings
This study may give the impression that to lose weight, you should avoid potato chips, potatoes, red meat and sugar and opt for healthier choices like fruits, vegetables and legumes. No nutritionist would likely argue any different. The real question is why these particular foods were more or less related to weight fluctuations. Nothing inherent exists in any of these particular foods that make weight-loss or weight-gain more likely, with the exception of calories. Fatty foods, such as potato chips and red meat naturally contain more calories than foods high in protein and carbohydrates. Consuming extra potato chips is therefore more likely to lead to weight-gain than bingeing on carrots. Potatoes, and other starchy foods, have long been known to contribute to weight-gain because of their starch content. Starch is a complex carbohydrate composed entirely of glucose. The body quickly breaks this carbohydrate down into its basic glucose molecules and uses them fore cellular energy. Because of this quick absorption, the body is often left feeling hungry shortly after eating, causing you to crave more calories. This also holds true with simple carbohydrates — particularly added sugars like those in soft drinks and juices.
Argument for Calorie Counting
Ultimately, your body weight comes down to the number of calories you consume versus those you expend through physical activity. While certain foods such as fried, packaged, processed, sugary and fatty foods making consuming extra calories more likely, they do not contribute to weight-gain any more or less than fruit, vegetables and nuts. Researchers from the Harvard study suggested that yogurt was healthy because it contains a bacteria that helps you feel full. However, this bacteria does not inherently result in weight-loss, it simply makes you not crave extra calories. In fact, low-carb diets are primarily effective because they cause dieters to focus on cutting calories — not due to the conception that additional carbohydrates are stored as fat.
If you’re attempting to lose weight, there are no secrets or gimmicks. The most effective and healthiest way to lose weight is to cut a moderate amount of calories from your diet, eat a variety of foods and increase your physical activity level. Eat plenty of fruits, vegetables, whole grains and legumes and avoid foods high in fat and sugar. Regardless of your caloric intake, you should obtain about 50 percent of your total calories from carbohydrates, 30 percent from fat and 20 percent from protein. Aim to get at least 30 minutes of moderate aerobic exercise, five days a week.