Protein

Definition

Proteins are long chains of amino acids that ensure structure, movement, immune defense and regulation of numerous biological functions.

How it works

There are 20 amino acids, 9 of which are essential and must come from food. Animal proteins contain all essential amino acids. Plant proteins, incomplete alone, can be combined. 1g of protein provides 4 kcal.

Role

Build and repair tissues, produce enzymes and hormones, transport oxygen (hemoglobin), defend (antibodies).

Examples

• Chicken, egg, fish, lentils, chickpeas, tofu, quinoa

Recommendations

0.8g/kg/day for sedentary adults, 1.2-2g/kg for athletes. Vary animal and plant sources.

Key takeaway

Proteins are irreplaceable — no other molecule can perform their structural functions.

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