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What works best for weight loss: low carb or low fat?

Dinner plate setup

Federal dietary guidelines for Americans say this is how to fill your plate: Carbohydrates, 45 to 65 percent (all ages); Protein, 5 to 20 percent (ages 1 to 3), 10 to 30 percent (ages 4 to 18), 10 to 35 percent (age 19 and older); Fat, 30 to 40 percent (ages 1 to 3), 25 to 35 percent (ages 4 to 18), 20 to 35 percent (age 19 and older).

Are low carb or low fat diets best for losing weight? "I don't think either is an effective way of going about losing weight," says Kerry Dal, a registered dietitian in Upstate's Bariatric Surgery Center.

“Truly, truly, it is a healthy balance of carbohydrates, proteins and fats. With exercise, with movement. You need an active lifestyle, in some form.”

Dal says people who try to lose weight may try diets that cut out fats, or cut out carbs. Neither is effective, long term.

Most people who overeat, overeat on carbohydrates. When they go on a low-carb diet, they may see a rapid weight loss -- from a loss of water. For every gram of carbohydrate the body stores, it stores two grams of water. “When you stop eating carbs and start burning them out of your body, all that water is going with them,” Dal explains.

Also, people following low-carb diets tend to ingest large amounts of unhealthy fats.

Following a low-fat diet does not guarantee weight loss. Consider that a gram of carbs and a gram of protein each contain 4 calories. A gram of fat contains 9 calories. If you cut the fat from your diet, you may lose the satiety factor, and overcompensate with carbs. That may leave you with the same – or greater – overall calorie intake.

Entirely cutting out fats is dangerous, too. “Your body actually needs fat,” Dal says. “Vitamins A, D, E and K are fat soluble. They need fat in order to be absorbed.”

She says if you‘re trying to lose weight, the best strategy is to incorporate regular exercise, eat the proper amounts of the macronutrients (carbs, proteins and fats) and make sure the calories you eat don‘t exceed what you need.