What is protein?
Protein is a vital macronutrient made up of amino acids. It is essential for building and repairing tissues, producing enzymes and hormones, fighting infections, and supporting nearly every bodily process. Protein is found in every cell of the body and is critical for growth, repair, and overall health.
Building Blocks of Protein
- Proteins are made of long chains of amino acids connected by peptide bonds.
- There are 20 different amino acids.
- 9 are essential → the body cannot make them, so we must get them from food.
- 11 are nonessential → the body can produce them.
Functions of Protein
- Enzymes – speed up chemical reactions in the body.
- Hormones – regulate processes like growth and metabolism.
- Antibodies – support the immune system.
- Structural components – build muscles, skin, hair, nails, and connective tissues.
- Energy source – provides 4 calories per gram (though the body prefers carbs and fat for energy).
Protein Synthesis
- The body constantly makes new proteins based on instructions from DNA.
- Old or damaged proteins are broken down, and the amino acids are recycled to build new ones.
Dietary Sources of Protein
- Animal-based: meat, fish, poultry, eggs, dairy.
- Plant-based: beans, peas, lentils, nuts, seeds, soy, whole grains.
Why Protein Matters
- Supports growth and development (especially important for teens).
- Repairs muscles and tissues after activity or injury.
- Helps regulate body processes through hormones and enzymes.
- Strengthens the immune system.