Research Says Junk Food Is Not the Cause of Obesity: What Is?

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Whether your greatest indulgence is sweet or salty, we all have our food temptations. According to the National Institute of Diabetes and Digestive and Kidney Diseases, more than two-thirds of American adults are considered overweight or obese, and many signs point to junk food and extra sugar as the leading problem of obesity. While junk food does play a major problem, a recent study points to quantity of food, rather than quality as the leading reason for obesity.

The new study, conducted by co-directors David Just and Brian Wansink of the Cornell University Food and Brand Lab, finds that eating junk food may not be as closely related to a high adult BMI as people commonly believe. This study points to one concept: What you actually consume matters less than the total amount of food you consume — but there is a catch.

To conduct the study, Just and Wansick reviewed a sample of adults from the United States. According to the study, “The consumption frequency of soda, candy, and fast food is not linked to Body Mass Index (BMI) for 95% of the population. The exception is those who are on the extreme ends of the BMI spectrum: those who are chronically underweight and those who are morbidly obese.” 

Based on this, for Americans who fall in the normal BMI range, eating junk food in moderation will not derail their weight goals. The catch: Those who have extreme BMIs (either low or high) will be affected by eating junk, even if it is not in excess. 

“This means,” Dr. Just explains in the study, “that diets and health campaigns aimed at reducing and preventing obesity may be off track if they hinge on demonizing specific foods.” He adds, “If we want real change we need to look at the overall diet and physical activity. Narrowly targeting junk foods is not just ineffective, it may be self-defeating as it distracts from the real underlying causes of obesity.”

Often, extreme diets can just promote binge-eating later on, which has more harmful consequences than eating some fries here and there, according to the study. So if you want to lose weight, what’s the key? Moderation and physical activity.

The problem is that junk food is addictive, which often leads us to eat an entire bag of chips instead of one small handful. According to a study published in The American Journal of Clinical Nutrition, junk food can actually alter your brain chemistry, causing your brain to think of junk food in an addictive way, similar to its reaction to drugs.

So, while a small amount of fries or cookies doesn’t directly affect BMI, junk food is easy to become addicted to, meaning eating junk in moderation is easier said than done. To keep your junk food consumption to a minimum, keep healthy snacks in your kitchen so you have other things to eat.

Also, as The Cheat Sheet has covered, weight loss (or gain) can be predicted by your kitchen counter. So, by keeping junk food off the counter, you may be able to resist some of those midday and late-night cravings. To put it simply: out of sight, out of mouth.

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