How High Homocysteine Levels Can Affect Your Heart and Blood Vessels

Cardiovascular disease is a group of diseases that affect the heart and blood vessels in the body, and it’s the number one cause of death and disability in the world.¹

Two of the most common types of cardiovascular disease are heart attacks and strokes. 

It’s well known by many people that there are certain factors that increase the chance of having a heart attack or stroke. These risk factors include:²

  • Smoking tobacco

  • High cholesterol

  • High blood pressure

  • Diabetes

  • Obesity

  • Lack of physical activity

  • Poor diet

The majority of my patients are looking to improve their overall health and decrease their risk of having heart attacks, strokes, and other types of cardiovascular disease. So while my initial appointments with them include reviewing the above risk factors, there is something else that I always add to their initial blood work: homocysteine levels.

The effect that homocysteine has on the heart and blood vessels in the body has been studied since the 1990s, yet I find that most of my new patients have never had their levels checked.

The cause of high levels of homocysteine ranges from certain diets, medications, medical conditions, and even genetic mutations. If you’re found to have high levels of homocysteine, it’s treatable with certain supplements and dietary changes. 

Keeping a close eye on homocysteine levels in your body is so important because high levels of it can increase your risk of having something called atherosclerosis, which can lead to a heart attack or stroke.³

What Is Homocysteine?

Homocysteine is an amino acid in the body that’s produced after the body breaks down something called methionine. We get methionine from our diet, and high levels of it are found in animal protein.⁴

In the body, homocysteine causes the release of several different inflammatory chemicals called cytokines.⁵ While cytokines are important when it comes to a healthy immune system, too many cytokines can cause increased inflammation in the body. This can then result in damage to delicate parts of the body like the heart and blood vessels.

Homocysteine also causes reactions within certain cells in the body that lead to the production of low density lipoproteins (LDL). This is also known as “bad cholesterol.”⁵ And it’s not really “bad,” it just pulls cholesterol out of the liver and puts it into the bloodstream. 

High levels of homocysteine have also been found to be associated with:⁶

  • Alzheimer’s disease

  • Birth defects

  • Blood clots

  • Cancer

  • Coronary artery disease

  • Dementia

  • Endothelial damage

  • Miscarriage

  • Myocardial infarction (a heart attack)

  • Parkinson’s disease

  • Pre-eclampsia

  • Stroke

All of us will have a certain amount of homocysteine in our body. What’s important is making sure that levels of it don’t get too high, which is called hyperhomocysteinemia, as this can poorly affect our heart and blood vessels.

How Does Homocysteine Affect the Heart and Blood Vessels?

The effect that homocysteine has on the heart was first discovered by Kilmer McCully, MD in 1999. He discovered that high levels of homocysteine in the body are associated with cardiovascular disease.⁶

Since then, research has continued to show the relationship between high levels of homocysteine, inflammation, and the risk of heart attacks and strokes.⁷ But despite this, many of the tools that doctors use to predict someone’s risk of cardiovascular disease don’t include homocysteine levels. 

Studies have shown that only about 50% of cardiovascular disease can be explained by the typical risk factors mentioned above. But there are still a large number of patients without typical risk factors that suffer from heart attacks and strokes, and some of this can be attributed to homocysteine levels.⁴

Because of homocysteine’s inflammatory ehe body, this can result in damage to endothelial cells in the body. These cells cover the inside walls of blood vessels in the body. When damage to this lining occurs, white blood cells rush to the site of damage and work to fix it. But by doing so, the body forms the perfect opportunity for plaque to build up.⁸

Over time, this plaque build up causes atherosclerosis, which leads to many heart attacks and strokes. 

When plaque builds up in the coronary arteries that supply blood to the heart, this can increase the risk of a heart attack. And when plaque builds up in arteries that supply blood to the brain, this can increase the risk of having a stroke. This is why it’s so important to find out if you have high levels of homocysteine and work to get it treated.

What Causes High Homocysteine Levels?

There are many different causes of high homocysteine levels, and they vary from your diet, lifestyle, and even genetic mutations.  

Diet and Lifestyle 

In order to properly control the amount of homocysteine in the body, our bodies need enough of these vitamins in their methylated, or usable, form:⁴

  • Folic acid

  • Vitamin B6

  • Vitamin B12

When we don’t eat enough of the above vitamins in their methylated form, our bodies don’t have what it needs to keep homocysteine at a safe level. Because of this, people with low levels of folic acid, vitamin B6, and vitamin B12 have been found to have high levels of homocysteine.⁴

It’s also been found that certain lifestyle factors are associated with increased homocysteine levels. These include:⁴

  • Alcohol use

  • Tobacco use

  • Coffee intake

  • Older age

  • Menopause

Medications

Certain medications that lower levels of folic acid, vitamin B6, and vitamin B12 metabolism inadvertently cause high levels of homocysteine.⁴

Some medications that have been found to increase homocysteine levels include:⁹

  • Aspirin

  • Acid-blocking medications like Prilosec and Pepcid

  • Asthma medications like Pulmicort and Flovent

  • Hydrochlorothiazide and Lasix, which are used to treat high blood pressure

  • Cholestyramine, which we use as a binder for mold illness

  • Estrogens

  • Carbidopa/levodopa, which is used to treat Parkinson’s disease

  • Anti-seizure medications

  • NSAIDs, such as ibuprofen and advil

For a complete list of medications that increase homocysteine levels, check out the article by David Perlmutter, MD at the link below.

It’s important to be aware of any medications you take that can cause decreased levels of these vitamins. If you do take these medications, you’ll likely benefit from taking a supplement and having your levels closely monitored by your doctor. 

Medical Conditions

There are certain diseases that have been found to be associated with high homocysteine levels. Some of these medical conditions include:⁴

  • Thyroid disease

  • Kidney disease

  • Cancer

  • Psoriasis

  • Diabetes

There are also certain medical conditions, specifically ones that affect the stomach and intestines, that cause decreased levels of folic acid, vitamin B6, and vitamin B12. This is largely because these conditions impact the body’s ability to absorb these vitamins, which then can result in high levels of homocysteine. These conditions include:¹⁰

  • Celiac disease

  • Tropical sprue

  • Short bowel syndrome

  • Amyloidosis

  • Having gastric bypass surgery

If you have any of these conditions, it’s important to be aware that you’re at an increased risk of having high levels of homocysteine. 

Genetic Mutations 

There are certain genetic conditions that can cause homocysteine levels to be very high. One genetic cause of high levels of homocysteine is a mutation of the Methylenetetrahydrofolate reductase (MTHFR) gene. One of the functions of the MTHFR gene is to control certain pathways in the body that regulate levels of homocysteine.¹¹

Mutations in the MTHFR gene are estimated to occur in about 38% of the population.¹² If you have a mutation in the MTHFR gene, this basically prevents our bodies from properly using folic acid, vitamin B12, and vitamin B6, unless they’re in the methylated forms. And when our body doesn’t have enough of these vitamins in the correct form, homocysteine levels rise. 

Can I Get Tested for MTHFR Gene Mutation? 

Yes, you can have testing done to see if you have mutations of the MTHFR gene. This isn’t a test that I typically run because it doesn’t tell us specifically if you’re “expressing” that genetic mutation. Expressing a gene basically means that it’s active and having an effect on your body. 

If you only have one mutation of the gene, you have a 30% chance of expressing it. But if you have two mutations of the gene, you still only have a 60% chance of expressing it. 

This is the trouble with genetics - it only gives us probabilities and never a definitive answer as to what our body is actually doing. 

How Can I Get Tested for High Homocysteine Levels?

As I mentioned before, homocysteine is something that I check in all of my patients. If you haven’t had your levels checked before, if you’ve developed one of the above medical conditions, or started taking a medication that can affect B vitamin levels, I highly recommend that you get your levels checked. 

You should be able to ask your primary care provider to add homocysteine levels onto your next set of blood work.

Once you get your results back, it’s important to carefully review them with your doctor. Many laboratories have a “normal” range for homocysteine levels that goes up to 15. However, homocysteine levels should not go above seven. So if you get tested and your levels are above seven, I recommend that you get treatment. 

I Have Cardiovascular Disease - Why Haven’t My Homocysteine Levels Been Checked?

Homocysteine is not something that’s typically checked by western medical physicians unless they’re interested in doing so. To assess someone’s cardiovascular health, western medical physicians will typically check cholesterol, triglycerides, and glucose on blood work. 

And even though both the Cleveland Heart Lab and the Boston Heart cardiovascular panels include homocysteine as part of their cardiovascular risk assessment, it’s still not standard in general medical practice.  

I believe that checking homocysteine levels is probably not standard because there are no particular medications to treat high levels of it. However, taking a specialized B vitamin supplement does treat high homocysteine levels. I’ve seen this work for years in my practice to help decrease elevated levels and to help patients reduce overall inflammation levels in their bodies.

How Are High Homocysteine Levels Treated?

Hyperhomocysteinemia, or high levels of homocysteine in the blood, can be treated by taking a specialized B vitamin supplement. It’s important to note that not all vitamin supplements are created equal. In order for the body to best absorb the vitamin you’re taking, you need to take a methylated version of the B vitamins. 

When we eat foods that contain B vitamins, our body breaks them down from their unusable (non-methylated) form to their usable (methylated form). So by taking a methylated version of B vitamins, you’re essentially skipping this step and giving your body a form of the vitamin that can be used immediately. 

Taking methylated B vitamins allows your body to better regulate and lower homocysteine levels. This is especially important if you have a MTHFR gene mutation. 

The supplement I recommend to my patients is called Homocysteine Supreme. The dose is one capsule daily in the morning. I recommend taking it in the morning as sometimes B vitamins can keep people awake at night because they give people more energy. If you want to try taking this, you can order it where I get my supplements at the link below.

The other thing I recommend to my patients when it comes to treating high levels of homocysteine is their diet. I recommend cutting out or greatly reducing all other versions of folate, vitamin B6, and vitamin B12 in your diet. This is because they may bind to receptor sites and prevent our bodies from taking in the methylated versions of what we need.

The biggest thing to reduce in your diet are food products that have been "fortified" with folate or B vitamins. Some examples of this are flour products or cereals that have added folate, vitamin B6, or vitamin B12. The vitamins that are added to these foods are typically not the methylated versions, and if they are, it’ll say methylated on the label. 

When eaten, the non-methylated vitamins can bind to the same receptor sites in the body that the methylated vitamins can. However, the non-methylated vitamins will not be able to activate the essential processes needed to keep the body working properly. This includes regulating and lowering homocysteine levels. 

Many multi-vitamins do not have methylated B vitamins in them, so make sure you’re taking one that does. But because of increased research and awareness surrounding the MTHFR gene, there are many more methylated B vitamin supplements on the market now.

Should I Get My Homocysteine Levels Checked? 

As you now know, high levels of homocysteine can increase your risk of having a heart attack and stroke - even if you don’t have “typical” risk factors. This is because of the inflammation that homocysteine causes within the cardiovascular system. 

I check homocysteine levels in all of my patients, and I recommend that you get your level checked with your doctor. You may find that you have high levels of homocysteine, and you can work to get this treated with supplements and dietary changes. 

And who knows? It just may save your life.