participants stayed in the unit 24 hours per day for two extended visits , eating the same food and doing the same activities .
his model simulations showed that only the carb - restricted diet while fat has the most benefits for losing body fat .
in a paper published august 13 in cell metabolism , the reduced - carb diet reduces insulin and increases fat burning .
since 2003 , kevin hall , phd -- a physicist turned metabolism researcher at the national institute of diabetes and digestive and kidney diseases -- has been using data from dozens of controlled feeding studies conducted over decades of nutrition research to build mathematical models of how different nutrients affect human metabolism and body weight .
the research was conducted at the national institute of diabetes and digestive and kidney diseases ( niddk ) , part of the national institutes of health .
i wanted to rigorously test the theory that carbohydrate restriction is particularly effective for losing body fat since nih study finds cutting dietary fat reduces body fat more than cutting carbs in a recent study , restricting dietary fat led to body fat loss at a rate 68 percent higher than cutting the same number of carbohydrate calories when adults with obesity ate strictly controlled diets .
carb restriction lowered production of the fat - regulating hormone insulin and increased fat burning as expected , whereas fat restriction had no observed changes in insulin production or fat burning .
 
these findings counter the theory that body fat from fat tissue and increasing the amount of fat burned .