Eating Healthy but Gaining Weight

Choosing "healthy" foods may actually increase your caloric consumption.

Posted Mar 20, 2015

“Low fat,” “All natural,” “Gluten free,” ”Organic,” “No trans fats,” “Non-GMO.” You’ve seen these terms hundreds of times in ads and on food packages. The obvious implication is that the food inside is good for your health. Whether there’s any validity to the implied health benefit is a topic for nutritionists to study, but I’m always a little suspicious when I see claims like “All Natural” or “Low Fat.” After all, rattlesnakes, poison ivy, and mosquitoes are "all natural," but we go to great lengths to avoid them, and "low fat" usually means that there’s added sugar. Just because something is all-natural, low fat, organic, or any of the other health claims doesn’t mean it’s good for your health or that it will help you lose weight.

For folks who are trying to lose weight, these terms—suggesting that the food is healthy—often are a license to eat more of the food. This phenomenon has been dubbed the “health halo.” When one aspect of the food is seen as healthy, it may lessen dietary restraint. In an informal survey reported in the New York Times, people were shown pictures of either a restaurant meal or the same meal with the addition of two crackers. The cracker wrapper was labeled “Trans Fat Free.” The participants were asked to estimate the number of calories in the meal. Although the crackers actually added 100 calories, estimates of the meal with the crackers were 199 calories lower compared with the cracker-free meal. The words “Trans Fat Free” on the package had the effect of mentally erasing 199 calories.

The health halo also shows up when eating out. Compare your image of McDonald’s to Subway restaurants. Most people view Subway as offering healthier, lower-calorie meals. In one study participants estimated that a 12-inch turkey sandwich from Subway had 200 fewer calories than a Big Mac, even though they both had about 600 calories. In a related study, when participants were given the opportunity to have a drink and a side order with their sandwich, participants were more likely to order a larger drink and a cookie when the main course was a Subway sandwich rather than a Big Mac. Thinking that they were making a healthy choice gave the participants permission to indulge when choosing drinks and side orders. As a result they consumed more calories than they would have had with the Big Mac, the “less healthy” choice.

The simple strategy for avoiding the additional calories from the health halo is being aware that a food portrayed as having a health benefit doesn’t do anything to help with weight control, and it definitely does not grant you permission to eat more because you’ve been “healthy.”