Reasons to Include Methionine in the Regular Diet

Amino acids, such as methionine, aren't only important as part of body proteins but they also have specific functions. Continue reading to find out more about it.
Reasons to Include Methionine in the Regular Diet

Last update: 20 September, 2021

The intake of methionine in a regular diet is important. This is because you can only obtain this amino acid that plays such a fundamental role in normal development through the food you eat.

Indeed, a methionine deficiency is rare, although it can lead to growth delay, muscle atrophy, liver damage, lethargy, and skin lesions. Today’s article will discuss its functions and the best food sources for it.

What’s methionine?

It’s an amino acid that contains sulfur — amino acids are the building blocks of proteins, the most important structural component in the body.

In addition, methionine is one of the nine essential amino acids for adults. None of them are more important than the rest and the body needs them all to be able to form its structures and perform certain functions.

However, essential amino acids differ from the rest because you can only get them through your diet. The body isn’t capable of synthesizing them and it’ll lead to a deficiency in those who don’t eat the necessary amounts.

The best sources of methionine in the diet

Foods of animal origin are the main sources of methionine because animal proteins are whole. What this means is they provide all the essential amino acids in the necessary amounts. Thus, the safe and highest contributions of methionine will be in:

  • Chicken, turkey, beef, and pork
  • Fish, especially in tuna, anchovies, mackerel, sardine, and haddock
  • Eggs
  • Parmesan, romano, gruyére, Tilsit or Edam cheese among others, and even in powdered whole milk

Animal foods aren’t the only sources though. In fact, certain foods like soybeans, chickpeas, quinoa, pistachios, and amaranth can provide whole protein.

Methionine is present in higher amounts in rice, quinoa, oats, Brazil nuts, and sesame, and in smaller amounts in legumes such as beans.

So, vegans should eat the right amount of whole grains, legumes, seeds, and nuts to obtain it.

A mediterranean dish can interact well with methionine.
Vegans can obtain methionine by learning to combine plant-based foods.

Ways to introduce methionine to your daily menu

Methionine must be present in the daily diet, just like any other amino acids the body needs. The best way to ensure adequate intake is to include good sources of protein at every main meal of the day.

This amino acid has many positive effects on the body but no nutrient is magic by itself. The most important thing is that it’s present in a balanced way and through a wholesome well-balanced diet.

As you can see, many other foods are great sources of protein and you can add them to a regular well-balanced diet. Thus, intaking the recommended amounts of methionine shouldn’t be a problem for healthy people with diets adapted to their needs.

In turn, an excess of methionine is harmful and leads to bad side effects. This is why you shouldn’t take any supplements unless a doctor prescribes them.

Possible negative health effects are linked to the appearance of homocysteine, which is another amino acid that appears as a result of methionine metabolism.

In addition, high levels of homocysteine in the body can cause inflammatory damage associated with vascular and neurological diseases. Some people are more susceptible than others.

Main functions of this amino acid in the body

As a component that’s part of proteins, methionine is necessary to build many of the main body structures such as bones, tissues, muscles. Also, it also forms part of enzymes, hormones, and membranes, and is necessary as a precursor of vitamins.

An array of food sources of vitamin B.
Amino acids are the minimal structures of proteins, both in food and in the body.

The other functions of methionine

  • It has an antioxidant effect as it’s able to transform methionine into cysteine. Cysteine, in turn, is a precursor of glutathione, a major antioxidant. Furthermore, glutathione can counteract free radicals and increases the life of some antioxidant vitamins, such as vitamin C and vitamin E.
  • It protects the cardiovascular system because sulfur amino acids, such as methionine and cysteine, play an important role in the degradation of lipids. This is why it can be helpful in lowering blood cholesterol and preventing the formation of arterial plaque.
  • It supports the normal action of the immune system. A regular normal dietary intake of cysteine and methionine is a must to synthesize these proteins.
  • Methionine has a high sulfur content. Moreover, this trace element is necessary to maintain certain body tissues, such as skin, hair, and nails in good condition.
  • It also has a detoxifying activity and can eliminate harmful substances such as heavy metals thanks to its sulfur content.

Adequate amounts in the diet and from good sources

In conclusion, methionine has important functions in the body as it’s a constituent part of proteins. Thus, it must be present in the daily diet because it’s a molecule the body can’t synthesize by itself.

A diet rich in quality protein foods guarantees the recommended daily amounts. Indeed, an excess of methionine could be due to a health problem, although it’s difficult to exceed the safe amounts through food alone.

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