The concept of energy balance has been in the news again this past week. Unfortunately, the media reports focused on controversial funding for a network of researchers, not on practical information that could help people with weight control. In my Health & Fitness column in the Aiken Standard this week I take the opportunity to explain what energy balance means and, despite the controversy, how it can help you achieve and maintain a healthy body weight.
First, it is worth explaining what energy balance means. Basically, the energy balance model suggests that your body weight is determined by the balance between the number of calories you consume and the number of calories you expend each day. It is often illustrated as “calories in, calories out” and is the basis for the most basic weight loss advice: eat less and move more.
Now for the controversy. It was recently reported that the Global Energy Balance Network (GEBN), an organization aimed at promoting activity and health, received money from Coca-Cola, a company that promotes the consumption of sugar-sweetened beverages. Furthermore, the obesity and exercise researchers at GEBN started focusing more on the lack of activity, instead of unhealthy food, as a major cause of obesity. Whether this is truly a real conflict of interest or simply a reality of funding a non-profit health organization remains to be seen.
It is important to note that this doesn’t mean that the efforts of GEBN scientists or the concept of energy balance in general should be dismissed. In fact, the energy balance model is a simple and effective way to explain how weight gain and weight loss occur. In fact, the only treatments we have for obesity focus on changing energy intake and energy expenditure. While some suggest that the “calories in, calories out” idea is too simplistic, it certainly helps people understand why they have gained weight and provides an intuitive guide to losing weight. This is most commonly expressed as “eat less, move more” and is the foundation of nearly every effective weight loss program.
For most researchers, practitioners, and people in general, the focus is typically on the “energy in” and “eat less” parts of the equation. Nearly all diets work by reducing the number of calories someone eats, even if they claim that you can eat as much as you want. Common recommendations to cut back on sugar or fat tend to lead to eating fewer calories, especially if those foods are replaced by fruits, vegetables, whole grains, and lean meats. Since we now know that eating fat won’t necessarily make you fat, the emphasis has shifted to sugar as a cause of weight gain. And sugar-sweetened beverages, including soda, are a major source of sugar for many people, especially children. So, most experts recommend consuming less soda, candy, and other sources of added sugar.
But there is another part of the energy balance model that can’t be ignored—energy expenditure. One goal of the GEBN is to emphasize the importance of activity in achieving energy balance and a healthy body weight. The focus on physical activity makes sense considering that the component of energy expenditure you can control is your activity level. This includes exercise, other occupational and leisure activity, and limiting sedentary (sitting) time, with a goal to be as active as possible throughout the day. The key is to achieve a balance between what you eat and drink and the energy you expend by being active.
The importance of exercise and energy expenditure for weight loss is shown by the members of the National Weight Control Registry, commonly called the “successful losers” because they have lost an average of over 50 lbs and kept it off for over five years. They lost weight by following a variety of diets and programs but nearly all continue to exercise regularly. This suggests that physical activity to promote “energy out” is at least as important as diet when it comes to maintaining weight loss.
In fact, if energy expenditure is high enough, a person could get away with eating almost anything he or she wants. In the 2008 Olympics, swimmer Michael Phelps famously revealed what he ate on a typically day. The amount and type of foods he consumed were not what you would expect from someone so fit and healthy! Without the hours of training he engaged in each day that diet would almost certainly have resulted in obesity and poor health.
Clearly, increasing physical activity is important both for weight control and health in general. But diet matters, too. And while the energy balance model says that there is nothing wrong with having your favorite foods or drinks as long as you are active, most of us could benefit from drinking less soda and moving a bit more. In this way, keeping yourself in energy balance should allow you to maintain a healthy weight without depriving yourself too much. The key is, and always has been, to find a balance between what you eat and drink and the energy you expend by being active.
Nutrition, exercise, and health information can be confusing. But it doesn't have to be that way. What can I help you with? firstname.lastname@example.org | http://twitter.com/drbrianparr