Do carbohydrates make you fat?
Text: Eleonora Seelig
Don’t eat carbohydrates after 6 p.m., or cut them out altogether: A low-carb diet is considered a promising weight-loss solution. But do you really have to deny yourself pasta and bread if you want to reach your dream weight?
Carbohydrates are one of the main nutrient groups in our diets and are an essential source of energy for the body, particularly the brain. There are three types of carbohydrate: sugar, starch and fiber. These differ in whether and how quickly they are digested and absorbed into the blood. Sugar provides a quick release of energy. With starch products, the blood sugar rises more slowly because the body needs longer to break them apart and process them. Fiber, meanwhile, is barely absorbed at all.
Western dietary patterns are largely to blame for carbohydrates being vilified as fattening. Highly processed foods with a high sugar content, such as soft drinks and sweet snacks, may contain lots of calories and quickly raise the blood sugar, but they don’t fill you up. Soon, you’ll start to feel hungry again and you’ll tend to eat more than necessary.
Calories are crucial
If your energy balance is positive in the long term — that is, if you consume more calories than you burn — you’re more likely to be overweight and develop secondary conditions such as type 2 diabetes or cardiovascular disease. It isn’t about how many carbohydrates a food contains, but rather the quality, portion size and how processed they are.
This applies in reverse as well: If you consume less energy than your body burns, and if you can keep this up long term, then you’ll lose weight — regardless of whether the calories come from carbohydrates, fats or proteins.
Low-carb diets may lead to short-term success, but in the long term they are less effective than a balanced diet with a moderate reduction in portions across all macronutrients — that is, fewer carbohydrates, fats and proteins.
Quality over self-denial
Eating good-quality food is more important than denying yourself carbohydrates. If you mainly eat unprocessed foods such as vegetables, fruit, pulses and whole grains, you’ll lose weight more sustainably than people who frequently eat highly processed products such as ready meals or industrially produced baked goods full of additives.
So it isn’t carbohydrates that determine what happens to your weight, but your calorie balance and the quality of your food. Finding a diet that fits in with your day-to-day life and takes into account your level of physical activity, for example, means you’re more likely to maintain your target weight in the long term.
Sources published in
Cochrane Database of Systematic Reviews (2022), doi: 10.1002/14651858.CD013334.pub2
and in Nature Medicine (2025), doi: 10.1038/s41591-025-03842-0
More articles in this issue of UNI NOVA (November 2025).