Low Carbohydrate Diet

Since 1860, and more recently, in 1972, low carbohydrate (low-carb) diets have been a strategy for weight loss. Today, there continues to be an interest in low-carb approaches. While all low carbohydrate approaches reduce the overall intake of carbohydrates, there is no clear consensus on what defines a low-carb diet. There are three macronutrients—carbohydrates (4 kcal/gm), fat (9 kcal/gm), and protein (4 kcal/gm) found in food. Therefore, studies have defined low carbohydrate as a percent of daily macronutrient intake or total daily carbohydrate load. We will define it here as: Very low-carbohydrate ( Low-carbohydrate ( Moderate-carbohydrate (26%-44%) High-carbohydrate (45% or greater) For reference, the Institute of Medicine proposes Americans obtain 45%-65% of calories from carbohydrates. This article will review the evidence and effectiveness of low-carb approaches in clinical medicine.