Protein, carbs, fat — the three macronutrients. Each gets demonised and glorified in rotating cycles. The honest reality from nutrition research: all three are necessary; the ratios matter less than quality and total intake; the rules are simpler than the internet suggests.

Protein

Role: builds and maintains tissue; strong satiety; highest thermic effect (20-30% burned in digestion).

How much: 0.8 g/kg for sedentary baseline; 1.2-1.6 g/kg for active people; 1.6-2.2 g/kg during fat loss or muscle gain.

Sources: meat, fish, eggs, dairy, legumes, soy. Plant combos (rice + beans) cover complete amino acid profiles.

Carbohydrates

Role: primary energy source for brain and intense exercise; supports thyroid function; fibre supports gut health and satiety.

How much: no strict minimum (body can run on fat), but most people feel and perform better with 100-300 g/day depending on activity level.

Sources: prioritise whole grains, legumes, fruits, vegetables. Refined carbs (white flour, sugar) aren't categorically bad, but low fibre → less satiety and faster blood-sugar rollercoasters.

Fat

Role: hormone production, fat-soluble vitamin absorption, cell-membrane integrity, concentrated energy.

How much: 0.5-1.0 g/kg minimum. Below that, hormones suffer.

Sources: olive oil, nuts, seeds, fatty fish, avocado. Saturated fat in moderation is fine (recent research has softened older views). Avoid trans fats.

The synthesis

Most healthy diets land somewhere between 20-35% protein, 30-50% carbs, 20-35% fat. Exact ratios are less important than adequate protein, high fibre, minimal processed food, and total intake matched to your goals. Anyone telling you otherwise is usually selling a specific ratio.