The lack of a consistent definition for "low carbohydrate diets" complicates efforts to compare studies throughout the literature [9]. While very low-carbohydrate diets are often defined by the absolute amount of carbohydrate intake, usually less than 70 g per day, other levels of dietary carbohydrate are usually defined based on the proportion of energy intake as illustrated in the Table 1. As the energy level of the diet decreases, the proportion of energy from carbohydrate increases. For example, a diet containing 200 g of carbohydrate might be classified as moderately low for a 2000 calorie intake, moderate-carbohydrate at 1500 calories and high-carbohydrate at 1200 calories. A recent systemic review of macronutrients in diabetes managementnotedthattheterms"conventional"or"traditional" carbohydrate diet were often used to describe the comparison diet for evaluation of lower carbohydrate diets [5•]. The review found that the terms “diabetic” or “ADA” were frequently used as well. In general, the comparison diets contained 55%–65% of energy from carbohydrate. However, national survey data suggest that people with diabetes consume an eating pattern that contains about 45% of energy intake from carbohydrate [10–12]. The assumption that the ADA recommends a specific level of carbohydrate intake is outdated as the current recommendation is for individualizing the macronutrient distribution [7•, 8]. In contrast to most low carbohydrate diets, which focus on number of g of carbohydrate or the percent of energy from carbohydrate [9], Paleolithic nutrition is based on the principles of evolutionary biology with a focus on the low carbohydrate options available to the hunter-gatherers [13–17]. This dietary approach, which is often referred to as the Paleo diet, targets restriction of grains, dairy products, and all refined food items. Carbohydrate sources that are encouraged include fruits, vegetables, and nuts. The total carbohydrate is approximately 35%–40% of energy intake although no specific amount is considered to be the goal. Paleo nutrition recommendations have been based on epidemiological studies of existing hunter-gatherer populations of today as well as archeological studies [13, 16, 17].
What are the Diabetes-Related Health Effects of Low-Carbohydrate Diets?
The metrics for evaluating the effectiveness of lowcarbohydrate diets in the management of diabetes include weight, glycemia, cardiovascular risk indices, and other health indicators