Understanding MTHFR and Homocysteine Levels

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Comprehending the Relationship between MTHFR Gene and Homocysteine Levels

Homocysteine plays an important role in the body. As an amino acid, the body breaks it down to create other compounds, along with certain nutrients, that perform different functions. 

Your genes play a role in the metabolism of homocysteine, with a particular focus on MTHFR.

This gene affects how your body uses the homocysteine to create other amino acids, antioxidants, and compounds. 

We will take a closer look at the connection between MTHFR and homocysteine and consider how certain mutations in your genes could result in elevated levels of this amino acid. 

How Your MTHFR Gene Uses Homocysteine

Methylenetetrahydrofolate reductase, also known as MTHFR, is a type of enzyme that forms part of your genes.

mthfr and homocysteine

It is involved in various processes, such as to break down homocysteine, amino acids, and certain vitamins.

The gene also plays a critical role in ensuring folic acid you get from food and supplements is converted into its active form, known as folate. 

You essentially have two of these MTHFR genes. Each of the genes comes from one parent. 

mthfr and homocysteine

Sometimes, there are mutations that occur within these genes. If only one of the genes is affected by these mutations, it is known as heterozygous. Homozygous refers to both of your MTHFR genes having mutations. 

Due to the role that MTHFR plays in the utilization of homocysteine, certain types of mutations can affect how much of this amino acid remains in your blood circulatory system. 

mthfr and homocysteine

In some populations, it is estimated that up to 25% of individuals have mutations in their MTHFR genes. 

When homocysteine breakdown is adversely affected by your MTHFR mutations, then your risk of certain health conditions may increase.

There are certain tests that can be done to determine if you have these mutations.

Additionally, you can get your homocysteine levels checked, which should ideally measure below 15 umol/L. Some people aim for an even lower number when testing and managing homocysteine levels. 

Risks Of Elevated Homocysteine Levels

If you have an MTHFR gene mutation that results in high homocysteine levels, then there are certain complications that can develop.

It’s important to understand these risks and look out for symptoms that may indicate complications. 

When you have high homocysteine levels in your blood, it puts you at a greater risk for the following complications and conditions:

  • Epilepsy
  • Stroke and heart attack
  • Parkinson’s disease
  • Dementia and cognitive impairment
  • Osteoporosis
  • Eclampsia
  • Atherosclerosis and other cardiovascular diseases
  • Formation of blood clots
  • Polycystic ovary syndrome
  • Inflammatory bowel syndrome

One thing to note is that acute high levels of homocysteine might not cause these particular problems. 

mthfr and homocysteine

The complications that we listed above are mostly associated with long-term exposure to high homocysteine levels, but it is still something that you should keep in mind. 

Other Factors That Can Lead To High Homocysteine Levels


Mutations in your MTHFR gene are one of the factors that can result in high homocysteine levels. 

There are, however, other factors that can also cause this complication in your blood circulatory system. 

It is important to have an overview of all potential risk factors and causes. Sometimes, a severe elevation in homocysteine levels can be the result of these factors, along with MTHFR gene mutations. 

Your body uses homocysteine along with folate, vitamin B12, and vitamin B6 to make other compounds.

If you have a deficiency of these vitamins, then your body does not fully utilize the homocysteine in your bloodstream, which can result in elevated levels. 

Some studies have found that people who follow diets that are restrictive tend to have a greater chance of deficiencies in these vitamins. 

mthfr and homocysteine

High alcohol consumption and cigarette smoking are also known to raise the risk, as well as age and family history. 


Mutations in the MTHFR gene are rather common and can result in high homocysteine levels in your blood circulatory system. 

Other factors can also increase homocysteine concentration, further contributing to the potential risks associated with the amino acid. 

While essential for the production of certain compounds, high levels of the amino acid can result in heart disease, cognitive impairment, and more. 

Blood samples can be used to detect homocysteine levels and to look for mutations in your MTHFR gene.