It doesn’t sound like much, but there appears to be a lot of power in 100 calories. In fact, some of the country’s leading obesity experts believe 100 calories may hold tremendous potential to stem the obesity epidemic.
In an excellent commentary in the Journal of the American Dietetic Association titled Using the Energy Gap to Address Obesity, James O. Hill and colleagues make a case for the “energy gap.” This term was coined to estimate the degree of change in the energy balance point that’s required to prevent weight gain or maintain weight loss. It’s a calculation based on ”calories in” vs. ”calories out.”
The researchers begin the article with evidence showing how our country got into the mess we’re in. Our collective poundage happened gradually over time — with the average American adult gaining 1 to 2 pounds per year. To prevent this weight gain, the researchers estimate that 100 calories a day change in the population energy balance could theoretically prevent weight gain in 90% of the U.S. adult population. That’s powerful stuff for such a small number.
To lose weight, the energy gap goes up — but not that significantly. The energy gap for weight loss is estimated to be 200-300 calories per day. The researchers suggest having a specific and achievable goal for changing diet and physical activity may be more beneficial than generic advice to eat less and exercise more.
This chart from the article shows the energy gap at work. For a 100-kg (220 lb.) person to lose 10% of body weight the energy gap is 190 to 200 calories per day. For the same person to lose 15%of body weight, the energy gap is 280 to 300 calories per day.
The continued rise in obesity rates makes you think that something isn’t working. I like the argument that Hill makes in the article. Do people feel overwhelmed by the thought of drastic lifestyle changes to lose weight? He’s been a major champion of the small-changes approach, aimed at helping people make small changes in lifestyle behaviors, which was the focus of a recent report of a joint task force of the American Society for Nutrition, Institute of Food Technologists and International Food Information Council.
There has been little long-term success in treating established obesity through lifestyle change, perhaps because of the large permanent changes in diet and physical activity required to keep weight off. An alternative strategy to address the obesity epidemic involves not focusing on weight loss but promoting small changes in diet and physical activity to initially prevent further weight gain. With the use of this strategy, obesity rates could first be stabilized in most populations and then, over time, decrease gradually. Supporting data show that small reductions in conscious energy intake and increases in physical activity can reduce excessive weight gain. The opportunity exists to use the small-changes approach to bring different stakeholders together to create a national initiative to address the global epidemic of obesity.
In the “energy gap” article, Hill and colleagues outline multiple ways to implement the energy gap and small changes concept. Research indicates that a small change focused on 100 calories is something that people can achieve and sustain. It’s a specific goal and people feel like they can do it. That may translate to eating 100 calories less (as easy as skipping that giant smear of butter on your bread, drinking water instead of a soda, or foregoing a second glass of wine). Or it could be increasing physical activity — such as taking 2,500 steps a day counted by a pedometer. Starting small is at least starting, and even little lifestyle changes can jump-start other healthy behaviors. But beyond preventing weight gain, taking an energy gap approach can make the task seem more achievable. Setting your sights on a 300-calorie deficit (to lose 15% of body weight) is a specific daily target that can be broken down between diet and physical activity changes.
The article ends with a call-to-action:
A small-changes approach must be included in public health strategies and in public policies to address obesity.
I agree. Let’s don’t overlook the power of small changes. Once again, less is more.
To get you started, here’s an excellent article on 10 easy ways to cut 100 calories every day.