What is a high-fat diet

More from The Art and Science of Low Carbohydrate Living: An Expert Guide to Making the Life-Saving Benefits of Carbohydrate Restriction Sustainable and Enjoyable by Dr. Stephen Phinney and Dr. Jeff Volek: When looking at studies about high-fat diets, it is important to know what is meant by a high-fat diet. Most consensus experts define a high-fat diet to be one with 45% – 60% of calories from fat. The authors of the book define high-fat to be 65% – 85% of calories from fat. The distinction is very important. Consensus experts will tell you that insulin resistance gets worse as fat in the diet increases, and this is true of the diets in the lower range. However, after fat intake goes above 60% of calories from fat, insulin resistance turns around and starts to improve. The benefits of a low-carb diet are found in the higher range of fat intake.