What are amino acids?

Amino acids are organic compounds that combine to form proteins , which are essential for our body. They are made of carbon, oxygen, hydrogen and nitrogen. Among its functions, amino acids help break down food, grow or repair body tissues, and can also be an energy source.

Amino acids are also responsible for allowing muscle contraction or maintaining the balance of acids and bases in organisms. Besides, each of the different amino acids has an independent function.


Amino acids are made up of an organic molecule with an amino group and a carboxyl group. Depending on their structure, they can be differentiated into L and D forms. L structures are natural for organisms, and therefore, the most important.

Generally, therefore, an amino acid is made up of carbon, carboxyl, an amino group, a hydrogen, and a side chain.


Of the nearly 250 amino acids that exist, there are 20 amino acids, called proteinogenic , which are considered important and essential for the proper functioning of the body and are divided as follows:

They are those that the body does not produce and therefore must be acquired through food: histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine.

They are the amino acids that the body does produce: alanine, asparagine, aspartic acid and glutamic acid.

They are necessary to alleviate certain diseases or stress: arginine, glutamine, tyrosine, glycine, ornithine, proline and serine.

Despite the names in their classification, both essential and non-essential have the same importance for the body, needing a balance between the amounts of both in our regular diet. This amount also varies in each person, being age or physical and mental wear variable factors in this regard.

Amino acids can also be classified under other criteria:

  • Depending on the number of acidic or basic groups in the molecule: acidic, basic and neutral (hydrophilic and hydrophobic).
  • According to its structure: aliphatic, aromatic and sulfur.

Foods rich in amino acids

Any food with a high protein content consequently has a high amino acid value. Therefore, foods such as milk , meat or fish are indicated for a diet with sufficient amounts of amino acids.

In a normal diet, to obtain the recommended amount to acquire all the necessary amino acids, a glass of milk per day is sufficient, or if you prefer other types of dairy, you can choose 150 grams of yogurt or cheese, for example. As for meat or fish, between 60 and 90 grams are more than enough to obtain all the amino acids. The exception in this case would be white fish or tuna, for which 140 grams are necessary. The eggs also fall into this group, two eggs equivalent to an amount sufficient protein.

As for other types of products, you can also obtain the amino acid supply that the body needs with 150 grams of legumes , 6 to 10 nuts , or even 110 grams of soy derivatives such  as tofu, spelled or quinoa.

Eggs and meat provide numerous amino acids to the diet.


The lack of amino acids in a diet can have consequences such as indigestion, depression  or delayed growth in children. There are also other factors that can make the body not have the amino acids it needs, such as infections, trauma, stress, or drug use.

In order to reverse a situation of insufficient amino acids, it is not recommended to eat a quantity of foods with a high protein content, since it can be harmful to health, but rather to adapt to a diet with an adequate and balanced amount of protein. In this way, the liver can correctly metabolize the ammonia of these amino acids, and does not pose any health risk.

One of the measurements that is usually carried out to check the level of amino acids in the body is an examination of plasma amino acids , for which blood is drawn from the patient in search of an excess or deficiency of these. A high level of amino acids can be the cause of eclampsia ( epileptic crisis , high blood pressure and proteinuria in pregnant women), intolerance to fructose, ketoacidosis or kidney failure; on the contrary, a low level can be the cause of fever, malnutrition or edema, among other problems.


Leave a Comment