Most people are under the impression that starchy foods such as bread and potatoes make you fat.
This is not the case – unless you cover your bread and potatoes with high-fat foods such as cheese, butter or sour cream.
Excess sugars and carbohydrates are stored as glycogen – not fats. Carbohydrates are not converted to fats. Animals, bacteria and fungi convert glucose to glycogen which is the form that glucose is stored.
Except in abnormal, extreme conditions, carbohydrates are not converted to fat in humans.
Consider the following.
As Marc Hallerstein, professor of Nutritional Science at Berkeley states:
Under most dietary conditions, the two major macronutrient energy sources (CHO and fat) are therefore not interconvertible currencies; CHO and fat have independent, though interacting, economies and independent regulation.3
A research team at University of Lausanne concluded:
One remarkable study from 1979 showed that be simply ADDING 12 slices of white bread (at 70 calories a slice) or high-fiber bread (at 50 calories a slice) to existing diet of overweight participants (a diet that resulted them in being overweight in the first place), resulted in an average weight loss of 9 kg over a period of 8 weeks. There was no change in their physical activity or exercise.5
The final paragraph is from a 2003 paper.
- Mann, J. & Truswell, A. S. (eds.) (2017) Essentials of Human Nutrition. Fifth Edition. London: Oxford University Press.
- Hellerstein, M. K. (2001) No common energy currency: de novo lipogenesis as the road less traveled. The American Journal of Clinical Nutrition. 74 (6), 707–708.
- Hellerstein, M. K. (1999) De novo lipogenesis in humans: metabolic and regulatory aspects. European Journal of Clinical Nutrition. 53 (1), s53–s65.
- Acheson, K. et al. (1982) Glycogen synthesis versus lipogenesis after a 500 gram carbohydrate meal in man. Metabolism. 31 (12), 1234–1240.
- Mickelsen, O. et al. (1979) Effects of a high fiber bread diet on weight loss in college-age males. The American Journal of Clinical Nutrition. 32 (8), 1703–1709.
- Saris, W. H. (2003) Sugars, energy metabolism, and body weight control. The American Journal of Clinical Nutrition. 78 (4), 850S-857S.