We all know people obsessed with fad diets — no carbs, high-protein, juice cleanses — but it seems it comes down to the simple fact that if you eat too many calories, you will gain weight. A new study says it doesn’t matter where those calories come from in your food, if you ingest a high amount of calories, you’ll pack on pounds.

Reuters cites a new study where researchers experimented with subjects on various levels of protein in their diets. They found that as calories increased, people on low-protein diets gained less weight overall, but lost muscle and replaced it with fat. High-protein diets added more weight, but subjects also gained lean healthy muscle.

But people in the low-protein group stored more than 90 percent of their extra calories as fat and lost body protein (muscle mass), while other participants gained both fat and healthier lean muscle, researchers reported in the Journal of the American Medical Association. So the groups all gained a similar amount of total excess fat.

A few nuggets of practical advice to take from this research — weight gain might not be the best way to judge how healthy a person’s diet is. In other words, the scale is not the be-all-end-all indicator of your health.

Basically, if you’re overeating and putting too many calories into your body, you will put on pounds. Eating healthier and exercising will trump any fad diets out there.

Calories, not protein, matter most for fat gain [Reuters]

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