How does protein affect your body?

17 June 2024

Whilst proteins are not your primary nutritional source of energy, proteins are utterly vital for the body’s energy systems. They are a main supporter of energy production, repair and tissue growth. Proteins also play a role in helping to regulate important hormones. Proteins are broken down to amino acids, which are known as the building blocks of the body. Optimising your nutrition will make a big impact on your health below the surface of the skin.Role of Proteins in Energy Systems

  1. Direct Energy Contribution:

    • Limited Use: Proteins are not the main fuel for energy. They usually provide less than 5-10% of energy needs, mainly during prolonged exercise when carbohydrate stores are low (Glycotic, Anearobic energy).

    • Amino Acids: Some amino acids from proteins can be converted into glucose in the liver, which can then be used for energy.

  2. Support for Energy Production:

    • Enzymes: Proteins make up enzymes that help speed up chemical reactions in energy pathways, like breaking down glucose.

    • Tissue Repair and Growth: Myofascial tears during exercise are common injuries that occur when muscle fibers and the surrounding fascia (connective tissue) are overstretched or torn. After exercise, proteins help repair and grow muscle tissues, which is essential for maintaining your body’s capacity to produce energy.

    • Transport Proteins: Proteins like hemoglobin (in blood) and myoglobin (in muscles) carry and store oxygen, which is crucial for the oxidative system (Aerobic energy).

  3. Hormonal Regulation:

    • Metabolic Hormones: Proteins form hormones like insulin and glucagon, which regulate blood sugar levels and energy availability.

    • Stress and Growth Hormones: Hormones like cortisol and growth hormone, also made of proteins, help manage energy reserves and support muscle repair.

Practical Implications

  1. Dietary Protein:

    • Athletes: Higher protein intake supports muscle repair and growth, helping improve performance and recovery.

    • Everyone: Adequate protein intake, approximately 0.8 – 1.5 grams per kilo of bodyweight, is essential for overall health and maintaining metabolic functions.

  2. Timing of Protein Intake:

    • Before and After Exercise: Eating protein before and after workouts helps with muscle repair and replenishing energy stores.

  3. Supplements:

    • BCAAs (Branched-Chain Amino Acids): Supplements like leucine, isoleucine, and valine can help reduce muscle breakdown and speed up recovery.


Adequate protein consumption is imperative for the body’s energy systems. However, they play a vital role in your overall health. The body performs a huge array of processes throughout the day. Ensuring you get enough protein, especially around exercise times, can help optimize your energy levels and overall health.