What are Amino Acids?

Amino acids are essential compounds common to all living things, from microbes to humans.
All living bodies contain the same 20 types of amino acids.

Amino acids make up about 20% of our bodies or about 50% of our solid body mass; they are the next largest component in our bodies after water. The body of a person who weighing 50 kg has about 10 kg of amino acids in their body make up.

Amino Acids are the building blocks of proteins. There are 100,000 types of proteins that are made up of just 20 amino acids.

Twenty types of amino acids make up the proteins for the human body.

What are essential amino acids?

Of total 20 amino acids, 9 amino acids cannot be synthesized in our bodies and we need to take them in through our diets. These are called essential or indispensable amino acids.
Essential amino acids are: Histidine, Isoleucine, Leucine, Lysine, Methionine, Phenylalanine, Threonine, Tryptophan and Valine.

What are non-essential amino acids?

The 11 remaining amino acids can be synthesized from other amino acids in the body and thus are called non-essential (or dispensable) amino acids.
Non-essential amino acids are: Alanine, Arginine, Asparagine, Aspartic acid, Cysteine, Glutamic acid, Glutamine, Glycine, Proline, Serine, and Tyrosine.

However, both essential and non-essential amino acids play an important role to support our life.

What are conditionally essential amino acids?

Some non-essential amino acids (e.g. Arginine, Cysteine, and Tyrosine) are called semi-essential or conditionally essential amino acids because they tend to run low during infancy or in health conditions such as being sick, injured or after surgery.

Read more about each Amino acid here:

What is role of amino acids in human bodies?

Amino acids which link together to make up proteins not only make up our bodies but also regulate most of the essential functions of our bodies. Some common examples of proteins are collagen, keratin, hemoglobin etc.

Amino Acids also regulate and maintain our body by becoming enzymes or hormones. Some commonly known hormones are Thyroid, Insulin, Adrenalin etc.

One more important function of amino acids is to supply energy to the body. Typically, a healthy body on an average diet uses carbohydrates as a primary source of fuel but proteins and amino acids can be used as a last resort when the primary sources are depleted due to rigorous exercise.

Amino acids also play an important role in food taste. Proteins do not have much taste, but every amino acid has its own taste, and the combination of these is one of the important factors in defining food taste. The most well-known amino acid is glutamic acid which is responsible for the fifth taste Umami and is also a raw material for the Umami Seasoning Ajinomoto®.

Since our bodies cannot make all amino acids, we must consume some necessary amino acids through our diets from various foods. A balanced diet complete with necessary amino acids is very important for proper function of body.

Amino acids balance

Obtaining balanced nutrition is important for a healthy life. It is necessary to get 5 major nutrients (proteins, fats and carbohydrates, plus vitamins and minerals) in a balanced way. Required daily intake of these nutrients is established by the World Health Organization (WHO) and in many countries. If this balance is broken such as any single nutrient is taken in excessively, the risk for obesity and lifestyle-related diseases increases.

Similarly, the required amounts of 9 essential amino acids for our body are defined by the international organizations (FAO / WHO / UNU). These are called the amino acids scoring patterns. If an amino acid is less than the amino acids scoring pattern, it is called the limiting amino acid. The nutritional value of a protein can be improved by supplementing the limiting amino acid. Amino acid score is a numerical value showing how much the smallest limiting amino acid satisfies the scoring pattern. It can be said that a protein with an amino acid score close to 100 is good quality protein.

In general, animal proteins such as eggs are good quality proteins with high amino acids scores. On the other hand, the scores of vegetable proteins such as wheat and corn are known to be low.

Understanding the amino acids balance in protein with the barrel theory

For a healthy life, it is essential to eat a diet with a proper balance of good-quality proteins; namely, essential amino acids, which cannot be made by the body. If amino acids are ingested in a proper balance, the body can effectively use them, and less waste will be excreted. A required daily intake is proposed for each of nine essential amino acids.

Balance of essential amino acids in food is often illustrated as a wooden barrel that is used for filling water. Each board of the barrel represents each type of essential amino acid in food. A food with an ideal balance of amino acids, such as an egg, has a barrel with every board neatly forming a line at the same height. In case of wheat, however, the boards are different in height. If any one of the boards is shorter than the others, you can only fill the barrel as high as the lowest board and the water beyond that runs out of the barrel. Similarly, if even one essential amino acid is absent, the remaining amino acids cannot be used effectively.

So, what would happen if amino acids lysine which is insufficient is added externally in the barrel for wheat? It has been found that the board for lysine gets taller, making other types of amino acids to be utilized more effectively.

This theory has been put to use for nutritional improvement in many countries with poor diets, contributing to the solution of social problems. For example, many countries in Africa have been suffering from poor development of infants due to nutritional deficiencies and resulting in high fatality rates.

*Koko, a porridge made from fermented corn is a traditional complementary food in Ghana. However, the levels of protein (amino acids balance) in koko do not meet the WHO’s nutrient requirements and dietary recommendations.
To address this nutrient gap, the Ajinomoto Group, in collaboration with various partners, developed KOKO Plus, a supplement containing amino acids and soybean proteins, which when added to koko during cooking, provides enough nutrients such as balanced protein along with Calcium, Iron, Zinc, Iodine, Folic Acid, Vit A, B1, B2, B6, Niacin, K1, D3, B12 for children. The World Food Programme (WFP) verified the efficacy of KOKO Plus and registered it as a “Nutritious powder” in its food basket in February 2018.

*The Koko Plus project in Ghana has been transferred to Ajinomoto Foundation since 2017

In our daily diets, high-lysine foods include dairy products, eggs, meat, fish, and bean whereas, rice has insufficient lysine. Thus, it is ideal to combine bean products such as miso and tofu with rice to secure intake of all essential amino acids. Eating mindfully considering the correct balance of amino acids is very important to have a healthier life.

The Ajinomoto group supports the healthy lives of people all around the world by unlocking the power of amino acids. Read more about our approach to Nutrition here.


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