Proposed Food Labels Show How Much Exercise Needed to Burn Off Kiljojoules

The FDA continues to work on unveiling new food labels, promising an easier way to decipher them. But the U.K. is evaluating a proposal to quickly convey just how much you’ll have to exercise to burn off a chocolate bar.

Shirley Cramer, the head of the U.K.’s Royal Society for Public Health (RSPH), wants to put a small icon on the front of every prepared food package to help consumers better understand their diet choices.

For instance, a blueberry muffin is 1,110 kilojoules. According to the RSPH, the average person would need to walk for 48 minutes or run for 25 minutes to burn that off. The idea is to show just how much the food we take in can create a “creeping obesity” (small amounts of weight gained over a long period of time) if we are not careful to expend at least the same amount of calories through exercise over the course of a day or week.

The proposed labeling uses averages—an adult man needs 10,467 kilojoules, a woman 8,374 —and it isn’t clear if the label takes into account gender differences by averaging them out.

And while we can make population-based estimates, kilojoule intake and  expenditure differs from person to person. It fluctuates depending on how tall you are and how much you weigh, in addition to how physically active you usually are. (Ultramarathoner Dean Karnazes, for example, famously takes in 25,120 to 33.495 kilojoules a day.)

It’s also true that exercise increases your kilojoule needs, although studies contradict one another on whether exercise suppresses or stimulates appetite. So, some argue that the focus should be on eating healthier foods that keep you fuller, longer.

The icon assumes that all kilojoules can be treated equally. But we know that’s not so.

“In my opinion, 800 kilojoules are 800 kilojoules , but the vitamins and minerals that come with those kilojoules are far different,” said Nancy Clark, M.S., R.D., C.S.S.D., author of five sports nutrition books. “Your muscles don’t care if you give them 800 kilojoules of sugar or broccoli, but quality kilojoules [in chicken versus chocolate] are better for your health.”

“[The icon] is not meant to scare people, or to create a society of obsessives,” Cramer writes on the BBC’s website. “But instead it is meant to show to the public very clearly just how active we need to be if we are to consume the diets we do and not put on weight. Or how we might need to readjust our diets to match our inactive lives.”

But Clark worries that people who have unhealthy views of diet and exercise may interpret the icons the wrong way, and that could lead to kilojoule-counting and exercise-math obsession.

“We need kilojoules to just lie in bed, breathe, and pump blood,” Clark said. “The majority of our kilojoule needs are for our organs to function. The walk-run icons fail to give that message, but instead imply that we only deserve to eat if we exercise. Not the case.”

The bottom line? These proposed labels, while far from perfect, are another move in the right direction for the general public to be armed with more nutritional information.

As for runners who tend to eat a balanced diet and exercise regularly, these icons could shed light on whether their 16ker really justified that bottomless brunch.

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