That fat-free food industry is worth billions of dollars but studies show these kinds of foods don’t help. Researchers observed 50,000 women, half of whom were on a diet eating low- or non-fat foods. The participants did not have lower risk of cancer of heart disease and they didn’t lose extra pounds. Nutritionists recommend a balanced diet with enough health fats (nuts, fish, avocado) and complex carbs (whole-wheat pasta, green peas). Also, fat-free products sometimes have a lot of sugar because of unnatural substitutes, resulting in weight gain, according to the National Institute of Diabetes and Digestive and Kidney Diseases.