A new study has suggested that cutting dietary fat is more helpful in losing weight more than narrowing the carbs.
Lead author Kevin Hall of the National Institute of Diabetes and Digestive and Kidney Diseases said that compared to the reduced-fat diet, the reduced-carb diet was particularly effective at lowering insulin secretion and increasing fat burning, resulting in significant body fat loss.
Hall said that the findings counter the theory that body fat loss necessarily requires decreasing insulin, thereby increasing the release of stored fat from fat tissue and increasing the amount of fat burned by the body.
In the study, the researchers studied 19 non-diabetic men and women with obesity in the Metabolic Clinical Research Unit at the NIH Clinical Center in Bethesda, Maryland.
Participants stayed in the unit 24 hours per day for two extended visits, eating the same food and doing the same activities. For the first five days of each visit they ate a baseline balanced diet.
Then for six days, they were fed diets containing 30 percent fewer calories, achieved by cutting either only total carbs or total fat from the baseline diet, while eating the same amount of protein. They switched diets during the second visit.
Hall said that their data explained that that when it comes to body fat loss, not all diet calories were exactly equal.
The study is published in the journal Cell Metabolism.