Homocysteine levels and why it is important

The Biomarker Handbook is a curated series that seeks to provide readers with insights on each biomarker we cover in our blood test packages and its relation to our body.

Homocysteine may not be something you have heard a lot about–or have even heard of, for that matter.

However, there are dangers of having abnormal serum levels of this key biomarker, both low and high.

Here is what you need to know about homocysteine, what it is, the dangers of having abnormal levels of it, and what to do if your levels are too low or too high.

What is Homocysteine?

In a nutshell, homocysteine is an amino acid. However, unlike some other amino acids, it is not available in foods we eat, and is instead produced by the body as a byproduct during production of the protein methionine. Homocysteine is present normally in very small amounts in our cells as the body quickly converts it into other products with the assistance of vitamin B12 and folate.

When there is significant deficiency of vitamin B12 and/or folic acid, then the conversion of homocysteine into other amino acids is deficient, causing an elevated homocysteine level.

An abnormal level of homocysteine can mean anything from vitamin deficiencies to renal disease. High levels of it (hyperhomocysteinemia) are associated with stroke and heart disease, and levels which are too low (hypohomocysteinemia) can elevate the body’s oxidative stress, as well as a few other important health consequences.

The Importance of Tracking Homocysteine Levels

Homocysteine is used to help determine if you are folate-deficient or vitamin B12-deficient; to determine if you are at increased risk of heart attack or stroke; to help diagnose a rare inherited disorder called homocystinuria.

High levels of homocysteine in the blood can cause irritation of the blood vessels, which can lead to an increased risk of hardening of the arteries. This, in turn, can lead to an elevated risk of heart attack, stroke and blood clots in the veins or arteries. Hyperhomocysteinemia is also seen as a predictor of Alzheimer’s disease.

One of the functions of homocysteine is to be the intermediate for the conversion of methionine into cysteine, which in turn helps produce sulfate, glutathione, and taurine. And, since glutathione is produced in response to oxidative distress, and taurine and sulfates are essential in the body’s detoxification process, hypohomocysteinemia can lead to a poor response to oxidation and toxicity.

The bottom line?

Homocysteine levels—either too low or too high—can have some profoundly negative health ramifications, making the tracking of levels a key measure in optimum health.

Signs and Symptoms to Watch Out For

One thing which should be noted with serum levels of homocysteine is that it may not be so much what symptoms to watch out for as it is which lifestyle and dietary habits to watch out for. This is because factors such as the amount of meat consumed, vitamin supplements used, or adherence to certain diets such as vegan are often to blame for an abnormal level of homocysteine in the blood.

An abnormal level of homocysteine can lead to a variety of disorders which can produce symptoms such as low energy levels, decreased vision and fatigue.

Other symptoms which may be related to high homocysteine levels are elongated limbs, high blood pressure, depression, and headaches. COnsider these to be warning signs that it is time to have your levels checked.

Consequences of Having Abnormal Homocysteine Levels

Homocysteine is an independent risk factor for the development of heart disease, stroke, and atherosclerosis. Patients with elevated homocysteine levels and abnormal serum lipids show a 40.9% increase in their risk for stroke, and an elevated homocysteine level can also increase the risk for heart disease by as much as 6 times over those of a normal level.

And, a high level of serum homocysteine has also shown to increase the risk of Alzheimer’s disease, something which can nearly double at a higher level.

However, hypohomocysteinemia (typically when levels drop below 4 umol/L) in patients with chronic kidney disease shows significantly lower rates of survival than of those with higher levels.

And, by decreasing the production of glutathione, sulfate, and taurine, hypohomocysteinemia also causes conditions associated with low levels of them, such as poor liver detoxification, inadequate bile production, accelerated aging, and cystic fibrosis.

Ways to Balance These Levels    

High homocysteine amounts can, in most cases, be normalised through simple dietary changes or vitamin supplementation.

For instance, hyperhomocysteinemia is most often caused by inadequate levels of vitamins B6, folic acid (B9), and B12, which means adding foods and/or vitamin supplements rich in these vitamins can lower homocysteine levels. Doctors may also prescribe medications high in B vitamins. Foods such as potatoes, eggs, beans, red meat, and fortified cereals contain high amount of vitamin B6. Green leafy vegetables such as spinach, fenugreek, turnip greens, asparagus have high folate content. Natural sources of vitamin B12 are found in fish, red meat, eggs, poultry, milk, milk products and cheese. Soy products and cereals also have high vitamin B12 content.

Anticoagulants such as aspirin may also be used to prevent blood clots in patients with elevated homocysteine levels, and foods high in methionine may also be restricted in the diet.

Low intake of vitamins B12 and folate paradoxically can lead to hypohomocysteinemia and adding foods or supplements rich in these key B complex vitamins can help elevate your homocysteine level.                       

When to See the Doctor

If you consume alcohol on a regular basis, drink coffee, have a poor diet, are vegan, or eat large amounts of meat, you should consider having their doctor test their serum homocysteine levels checked. Abnormal amounts of homocysteine may also be attributed to genetics, meaning family history and a review of any diseases or conditions which “run in the family” which may be related to homocysteine levels should also be reviewed.

And, those experiencing heart problems, stroke, or other cardiovascular maladies should also have homocysteine levels checked—though this is likely something a doctor will do anyway for patients with these symptoms.

Further Testing to Check for Ailments Related to Abnormal Homocysteine Levels

Ailments associated with an abnormal homocysteine level includes chronic kidney disease, stroke, heart attack and Alzheimer’s disease.

Testing for these conditions is recommended for those with abnormal homocysteine levels, as well as any testing necessary in determining the cause of the abnormal levels.

It is also recommended that those with a family history of a condition known as homocystinuria—a genetic condition which prevents normal metabolism of methionine, and thus, high homocysteine levels in the blood—be screened at birth. This is critical, since the condition can cause stunted growth, mental disabilities, myopia, osteoporosis and other dangerous, lifelong conditions if left unchecked.


Most of us may not be aware of the importance of homocysteine, its correct levels, and its association with the health of our body.

Awareness of diet, alcohol consumption and genetic disposition should also be considered when testing homocysteine levels. Improving your nutritional intake is an integral part of homocysteine management.

People with a family history of hyperhomocysteinemia, it is recommended that a screening at birth is performed, and that any symptoms are treated as early in life as possible.

Doing so could be a life saver!

If you want to learn more about homocysteine and how to keep your homocysteine level in check, read our lifestyle article here!

Interested in other biomarkers? Check out the rest of The Biomarker Handbook.

For more information, drop us a message and we will get back to you.

The post Homocysteine levels and why it is important appeared first on BioMark.