Low-fat diet. Low-carb diet. To the average person, the two are nearly synonymous in that there is a “low-something” that may contribute to a person’s weight gain. While fat needs no definition, carbohydrates usually elicits images of white bread and heavy starches like potatoes that provide a ton of energy (calories) but can be problematic when it comes to having them in excess, as they are converted and stored as fat, contributing to weight gain. The question then arises: which is better for you – a reduced-fat diet or a reduced-carb diet?
A study published by Cell Metabolism found that restricting fat consumption leads to more body fat loss in people with obesity than restricting carb consumption.
Additionally, the same study found limiting carb consumption resulted in greater overall weight loss compared to the reduced-fat diet. It also founded the reduced-fat diet led to decreased insulin secretion, increased fat oxidation, and increased body fat loss compared to baseline levels.
The study observed 19 adults with obesity who were confined to a metabolic ward for two 2-week periods. After determining baseline levels, the subjects were provided either a reduced carbohydrate diet or a reduced fat diet which they strictly adhered to. After a 2-4 week washout period, baseline studies would be conducted again and the subjects would then consume from the diet plan they were not originally given.
Low-Fat Diet The Way To Go
According to the study, body fat loss was determined by the difference between daily fat intake and net fat oxidation (the conversion of fat into smaller molecules that can then be burned off as energy). Though the reduced carbohydrate diet had greater increases in fat oxidation and the reduced fat diet had no change in fat oxidation, fat loss was greater in the reduced-fat diet.
The study also took care to make sure the diets had a measure of constancy. While both the reduced-calorie and reduced-fat diets were 30 percent less in calories than the baseline diet (2,740 calories), the diets themselves both had the exact same number of calories (1,918 calories). Protein levels remained unchanged for the most part, though the reduced-fat diet had an insignificant increase at 105 grams, while the baseline and reduced-calorie diets had 101 grams.
Bottom line: Calorie for calorie, the reduced-fat diet led to more body fat loss than the reduced-carb diet.