Though definitions of LCHF diets differ, the following three-tiered definition will be used in this paper.^[2]

• Moderate carbohydrate diet (26–45% of daily kcal)
• LCHF diet (<26% of total energy intake or <130 g CHO/day)
• Very LCHF (ketogenic) diet (20–50 g CHO/day or <10% of daily kcal of 2000 kcal/day diet)

Reduced carbohydrate diets are those that have carbohydrate intakes below the Dietary Guidelines for Americans (DGA) recommendations (of 45–65% of total energy intake). However, we define LCHF diets as those that restrict carbohydrate intake to 130 g/day or less. Very LCHF (ketogenic) diets may induce ketosis in some people. Though individual responses vary, ketosis usually occurs in people who restrict their carbohydrate intake to below 20–50 g/day with some degree of protein restriction.

Since the carbohydrate content of the diet is significantly reduced, the relative proportion of energy derived from protein and fat will increase. In practice, however, LCHF…