The “health halo” effect occurs when a food that has some healthy attri­butes is perceived as being virtuous in all respects. For instance, many people (mistakenly) think that organic foods are more healthful than their conventionally grown counter­parts—that they’re lower in calories and higher in fiber—when in reality the term “organic” refers only to the agriculture practices used and has nothing to do with health or nutrition.

This health halo phenomenon also exists when it comes to food-related behaviors, as was shown in two studies in the Journal of Marketing Research and Journal of Marketing. Here we report on their rather unexpected findings because it’s likely that many people fall victim to a health aura, even if they think they know better.

In the first study, people who were trying to lose weight consumed more trail mix when the package labeled it as a “Fitness” snack (and had an image of running shoes) rather than just plain “Trail Mix.” Moreover, when given the opportunity to use a stationary bike, the weight-conscious participants exercised less after consuming the trail mix labeled “Fitness” than when they ate the snack with the plain label. Rather than prime the participants to be more active, as might be expected, the fitness-branded food apparently served as a substi­tutefor exercise. Fitness branding may put dieters “in double jeopardy, because it makes them eat more and exercise less,” the researchers concluded.

The second study, from Harvard Business School and Duke University, looked at data from more than 2 million shopping trips at a major grocery store in California and found that people who brought reusable shopping bags bought more organic foods. That’s not surpris­ing since people who are more environmen­tally conscientious are more likely to support organic farming. But incongruously, they also chose more “indulgent” foods, like candy and chips. The laudable act of reusing bags, the authors noted, seems to give shoppers free license to indulge by helping them “feel more deserving and less guilty about doing so.”

Bottom line: To avoid being influenced by the health halo effect, ignore buzzwords, slo­gans, and images that make foods appear more healthful than they really are (flip the package over to read the nutrition facts). And be mindful that behaving “virtuously” in one area of your life (like using your own shopping bag) doesn’t give a green light to act in a neg­ative or overindulgent way elsewhere.

See also: Front-of-Pack Food Labels: Help or Hype?