Dietary fat

Dietary fat is a macronutrient that provides about 9 kcal per gram, compared with about 4 for carbohydrate and protein.^{1Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 204.} Omega-6 and omega-3 fatty acids are essential polyunsaturated fats the body can’t make; they’re needed for cell membranes, the brain and nervous system, and hormone production.^{1Haff and Triplett (eds.), Essentials of Strength Training and Conditioning, 4th ed., p. 204.}

At least 3% of energy from omega-6 and 0.5% to 1% from omega-3 prevents true deficiency, but inadequate intake can still be a problem for healthy clients who restrict fat too heavily.^{2Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 126.}

In practice

• Very-low-fat diets aren’t recommended for healthy, active clients: intakes under 15% of calories may reduce testosterone production and impair absorption of fat-soluble vitamins.^{2Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 126.}
• Fat’s high energy density and the ease of overeating high-fat foods mean trimming excess fat can lower calorie intake.^{3Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 127.} Check what the client eats first; their diet may already be low in fat.^{3Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 127.}
• A cholesterol-lowering diet belongs with a registered dietitian, outside a trainer’s scope of practice.^{3Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 127.}

How much dietary fat do clients need?

The NSCA’s personal training text reports that most health organizations suggest 30% of calories or less from fat, with less than 10% from saturated fat.^{2Schoenfeld and Snarr (eds.), NSCA’s Essentials of Personal Training, 3rd ed., p. 126.} ISSA gives an adult intake range of 30% to 35% of calories.^{4International Sports Sciences Association, Fast Track Study Guide: Nutrition, p. 3.}

Schoenfeld sets no percentage for lifters: fat fills the calories left after protein and carbohydrate, with a minimum of about 1 g/kg per day to prevent hormonal changes, based on limited data.^{5Schoenfeld, Science and Development of Muscle Hypertrophy, 2nd ed., p. 230.}