Protein is an essential macronutrient that plays a crucial role in the human diet. It provides the building blocks for muscle, skin, hair, and nails, and is necessary for growth and repair of tissues. Protein also helps to regulate hormones, enzymes, and immune function. In addition to its structural role, protein can also be used as a source of energy.
There are many good sources of protein in the human diet. Some of the best sources include:

• Lean meats such as chicken, turkey, and fish

• Dairy products such as milk, cheese, and yogurt

• Eggs

• Legumes such as beans, lentils, and chickpeas

• Nuts and seeds

• Soy products such as tofu and tempeh

• Whole grains such as quinoa and amaranth

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Amino acids are the building blocks of proteins, and they play a crucial role in various biological functions in the human body. Proteins are large molecules composed of long chains of amino acids, and they are essential for the structure, function, and regulation of tissues and organs.
There are 20 standard amino acids that the human body requires to synthesize proteins. Out of these 20 amino acids, nine are considered essential amino acids (Histidine, Isoleucine, Leucine, Lysine, Methionine, Phenylalanine, Threonine, Tryptophan, Valine)
because the body cannot produce them on its own, and they must be obtained from the diet. The remaining 11 amino acids are non-essential, meaning the body can synthesize them from other sources.
 
When we consume foods containing protein, whether from animal sources (meat, fish, dairy) or plant sources (beans, lentils, grains), the proteins are broken down during digestion into their constituent amino acids. These amino acids are then absorbed into the bloodstream and transported to various cells throughout the body.
Once inside the cells, the amino acids are used for protein synthesis, where they are assembled into specific sequences to form the proteins needed for various functions. These functions include building and repairing tissues (such as muscles, organs, and skin), producing enzymes and hormones, supporting the immune system, and serving as transport carriers for essential nutrients and molecules.
Having a balanced intake of essential amino acids is crucial to support optimal health, especially for growth, development, and maintaining bodily functions. A diet that provides all essential amino acids is often referred to as a "complete protein" source.

1. Alanine:

   • Deficiency: N/A (Alanine can be synthesized by the body).

   • Excess: N/A (Excess is usually metabolized by the body).

2. Arginine:

   • Deficiency: Impaired wound healing, skin rashes, hair loss.

   • Excess: May cause digestive issues.

3. Asparagine:

   • Deficiency: N/A (Asparagine can be synthesized by the body).

   • Excess: N/A (Excess is usually metabolized by the body).

4. Aspartic Acid:

   • Deficiency: N/A (Aspartic acid can be synthesized by the body).

   • Excess: N/A (Excess is usually metabolized by the body).

5. Cysteine:

   • Deficiency: Impaired growth, skin and hair issues.

   • Excess: May lead to oxidative stress.

6. Glutamic Acid (Glutamate):

   • Deficiency: N/A (Glutamic acid can be synthesized by the body).

   • Excess: N/A (Excess is usually metabolized by the body).

7. Glutamine:

   • Deficiency: N/A (Glutamine can be synthesized by the body).

   • Excess: N/A (Excess is usually metabolized by the body).

8. Glycine:

   • Deficiency: N/A (Glycine can be synthesized by the body).

   • Excess: N/A (Excess is usually metabolized by the body).

9. Histidine:

   • Deficiency: Growth impairment, anemia, skin issues.

   • Excess: May cause digestive issues.

10. Isoleucine:

    • Deficiency: Fatigue, dizziness, muscle wasting.

    • Excess: May compete with other amino acids for absorption.

11. Leucine:

    • Deficiency: Fatigue, dizziness, muscle wasting.

    • Excess: May compete with other amino acids for absorption.

12. Lysine:

    • Deficiency: Growth impairment, anemia, fatigue.

    • Excess: May cause digestive issues.

13. Methionine:

    • Deficiency: Impaired growth, skin and hair issues.

    • Excess: May lead to oxidative stress.

14. Phenylalanine:

    • Deficiency: Fatigue, mood swings, cognitive issues.

    • Excess: May compete with other amino acids for absorption.

15. Proline:

    • Deficiency: N/A (Proline can be synthesized by the body).

    • Excess: N/A (Excess is usually metabolized by the body).

16. Serine:

    • Deficiency: N/A (Serine can be synthesized by the body).

    • Excess: N/A (Excess is usually metabolized by the body).

17. Threonine:

    • Deficiency: Fatigue, poor immunity, growth impairment.

    • Excess: May compete with other amino acids for absorption.

18. Tryptophan:

    • Deficiency: Mood changes, sleep disturbances.

    • Excess: May compete with other amino acids for absorption.

19. Tyrosine:

    • Deficiency: Fatigue, mood changes, cognitive issues.

    • Excess: May cause digestive issues.

20. Valine:

    • Deficiency: Fatigue, dizziness, muscle wasting.

    • Excess: May compete with other amino acids for absorption.