Fact Check >> Can Low-Calorie Foods Help you Lose Weight?
Low-calorie foods are booming: cold cuts, milk, cheese, granola bars, soft drinks, salty snacks — there are “light” versions of all these foods and many more. We turn to “light” products because we want to eat healthy and hope they will help us lose weight. We automatically associate words like “sugar-free,” “low-fat,” or “wellness” with health and well-being. But do these “low-calorie” products really deliver what they promise?
What are “light” foods?
Wherever it says “light,” it means there is less of something: for example, less fat or less or no sugar. “Light” products have to contain at least 30% fewer calories than standard products. There are a lot of different terms for “light” products, but each term has its own meaning. Here is a list of the most common terms and their definitions:
- Fat-free: no more than 0.5 grams of total fat for a given serving size*
- Calorie-free: fewer than 5 calories for a given serving size
- % fat-free: must contain 3 grams or less of total fat for a given serving size. A “100% fat-free” claim can only be made for foods that meet the criteria for “fat-free” and also have less than 0.5 grams of fat per 100 grams and contain no added fat.
- Cholesterol-free: less than 2 milligrams of cholesterol for a given serving size and 2 grams or less of saturated fat for a given serving size
- Saturated fat-free: no more than 0.5 grams saturated fat per serving size, and no more than 0.5 grams of trans fatty acids
- Low-fat: 3 grams or less of total fat per serving size
- Low-calorie: 40 calories or less for a given serving size (except sugar substitutes)
- Low-cholesterol: up to 20 milligrams cholesterol and 2 grams or less of saturated fat for a given serving size
- Low-saturated fat: 1 gram or less of saturated fat per serving size and no more than 15% of calories from saturated fat
* The serving size represents the amount of food customarily consumed per eating occasion.
How does “light” affect taste?
Fat is an important flavor carrier because it absorbs and preserves flavors. Substances like glutamate, glycine, chlorides, lactates, yeast extract or flavors are often used to make up for the lack of taste of low-fat products. Many of these substances can cause headaches, diarrhea, polyuria or even allergic reactions.
Are light or low-calorie foods unhealthy?
More research is needed in order to clearly determine whether and how “light” foods affect our health. However, longitudinal study in Europe shows that even two glasses of sweet soft drinks per day can be harmful to your health. Interestingly, it doesn’t make a difference whether the beverages are sweetened with sugar or artificial sweeteners. There are also studies showing that artificial sweeteners can be detrimental to the health of our digestive tract.(1)
Switching to artificially sweetened beverages isn’t the right choice for diabetics either, because the regular consumption of diet sodas can be an independent diabetes risk factor. (2) The healthier and safer option is to drink water or unsweetened tea.
Beware of diet foods
Light or low calorie foods do not deliver what they promise! Just because they are low calorie, does not make them healthier; they may contain many substitutes. And as far as weight loss goes, long-term studies have shown that heavily processed diet foods contribute little, or none if anything, to weight loss.(3,4) We tend to eat more of something with a good conscience when the word “light” is written on the label. A better strategy would be to simply eat less of the standard product, which will result in weight loss.(5)
Takeaway: are low calorie foods healthy or unhealthy?
There is no clear evidence indicating how healthy or unhealthy light or low calorie foods are. The fact is that they don’t have any proven benefits for our health. They are not necessarily the most effective choice of foods for weight loss either. If you want to lose weight in a healthy way, the best route is to stick with natural, unprocessed foods and cut about 300 calories per day.