Macronutrient Guide

Why Macros Matter

The three macronutrients provide all dietary calories: protein (4 kcal/g), carbohydrates (4 kcal/g), fat (9 kcal/g). Total calorie intake determines whether you lose, maintain, or gain weight. Macro distribution determines body composition — specifically the ratio of fat to muscle in any weight change. Sufficient protein (1.6–2.2g/kg) while in a calorie deficit preserves muscle mass during fat loss. Without adequate protein, a significant proportion of weight lost comes from muscle, slowing meta

Protein Targets by Goal

General health (sedentary): 0.8g/kg (the RDA minimum). Recreational exerciser: 1.2–1.6g/kg. Fat loss (to preserve muscle): 1.8–2.4g/kg — higher end if also strength training. Muscle building: 1.6–2.2g/kg — above 2.2g/kg provides minimal additional benefit. Athletic endurance: 1.4–1.7g/kg. These are daily targets, best spread across 3–5 meals to maximise muscle protein synthesis (each meal should ideally contain 0.3–0.4g/kg protein, approximately 20–40g for most people).

Carbohydrates and Fat

Carbohydrates fuel high-intensity exercise (glycolysis) and support thyroid function and hormonal health. Going too low (under 100g/day) without following a strict ketogenic protocol causes fatigue and poor training performance. Fat is essential for hormone production, fat-soluble vitamins (A, D, E, K), and cell membrane integrity. Minimum fat intake: 0.5–0.7g/kg/day. The optimal fat:carb split below the protein target is largely personal preference — both high-carb/low-fat and moderate-carb/mod

Tracking and Flexibility

Tracking macros in an app (MyFitnessPal, Cronometer, MacroFactor) for 2–4 weeks provides invaluable insight into your actual eating habits, even if you stop afterwards. Common discoveries: underestimating portions, getting far too little protein, getting far too many calories from sauces and drinks. Flexible dieting (if it fits your macros / IIFYM) produces equivalent results to strict clean eating when calories and protein are matched — the evidence strongly supports this, removing the need for

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