The Importance of Homocysteine

A very important blood marker that is ignored and forgotten to be tested!
In this article, I would like to talk about the importance of Homocysteine. It is an amino acid that is produced by the body and usually is a marker when elevated helps to detect cardiovascular disease. Doctors only run it on a patient if they suspect any cardiovascular disease symptoms. In Functional Medicine, we also like to test for it because it gives us a window into if you are methylating properly or not.
The Importance of Homocysteine
The topic of Methylation is getting its fair share of attention lately and in my practice, I always talk about methylation and I make sure to test all my clients for Homocysteine. Methylation is a biochemical reaction in the body that regulates the activity of cardiovascular, neurological, reproductive, and detoxification systems including those related to:
  • Eye health.
  • Fat metabolism.
  • DNA production – cell division.
  • Neurotransmitters production – dopamine, norepinephrine, epinephrine, serotonin.
  • Gene expression – regulates the genes by turning them on and off and preventing the inherited genes from being turned on.
  • Immune cell differentiation – maturation of immune cells such as T cells and natural killer cells.
  • Detoxification – different pathways in the liver through phase 2, Glucuronidation, sulfuration, acetylation. If these are not functioning properly can lead to toxicity-related symptoms and poor clearance of substances.
  • Histamine clearance. If there is a buildup could cause clinical symptoms.
  • Estrogen metabolism and clearance are very important because they can increase oxidative DNA damage from certain estrogen seen in the 4OH phase 2 of the Dutch test. A very informative test that I usually run on most of my clients. It is very important for those patients/clients who show estrogen dominance receptors to check their methylation status to prevent estrogen receptor cancers.
  • Cellular energy metabolism and methylation play a critical role in the mitochondrial energy metabolism in every cell through its role in the biosynthesis of CoQ10, Carnitine, and ATP production which are the engines of your cells.


The body is a complex machine that has various gears and switches that need to be all functioning properly to operate optimally. Methylation is the mechanism that allows the gears to turn, and it turns biological switches on and off for a host of systems in the body.
Methylation can’t be tested, that is why I like to test the blood marker Homocysteine because I can get a very good idea about your methylation capabilities. The optimum range is between 5-7umol/L. I find many of my clients fall between 10 -12umol/L and that means that they require some support to function optimally.
I will not go into the technicality of how homocysteine and methylation are formed. What you do need to know is that the body must make homocysteine because it is an important block of two very important compounds in the body.
  1. It helps produce our methyl donor, SAMe. It gives away a methyl group to other substances in the body, which enables cardiovascular, neurological, reproductive and detoxification systems to perform their functions optimally.
    The system that produces SAMe is very dependent on B vitamins, especially Methyl Folate 5-MTHF known better as B9, and Methyl Cobalamin B12. Around 60% of the American population has a genetic mutation that makes it very challenging for their body to create enough 5-MTHF (I use these statistics since I am American educated).
    Since I run several kinds of testing on myself to understand them before administering them to my clients, I was very fortunate to learn that I fall into that category. I am heterozygous- meaning I carry only one allele of that gene vs two and I would always be dependent on a B complex to help me methylate properly.
  2. It is very important to produce glutathione which is our master antioxidant and without it, we would get into a lot of trouble because we would not be able to combat the oxidative stress in our body and remove heavy metals, especially mercury and lead and many other things.


  • We need B vitamins (B9 + B12) to help support the methylation cycle to produce Homocysteine.
  • Without Homocysteine and B6, we can’t make Glutathione .
  • B complex is essential for initiating the process.
If your homocysteine Is elevated (>7 umol/L) – then we need to understand what is causing the elevation!
  • Is it a diet and lifestyle issue?
  • Is it a gene issue?
  • Is it a B vitamin issue?
  • Is it Cardiovascular – elevated Blood pressure or diabetes?
What if your homocysteine was low (<5 umol/L)?
We never hear about that! Usually, if something is low (below RR) one seems to think, that is fine. The reality is far from the truth. When something is low, it also means that something is wrong.
Example: if we wanted to make a Romain salad. The main ingredient in the salad is the Romain if we don’t have that, can you make a Romain salad? No, you will make something else. Exactly what I am trying to say. If something is low then we don’t have enough of it hence something is wrong.
What could be the reason?
  1. Low protein consumption. We should consume 1 gram per 2 pounds of body weight. This is a rough guide. I can tell you that many people do not eat enough protein, and as we age, we are eating less and less and this is something we need to consider especially if we are also low in homocysteine.
  2. Low sulfur intake. We need to eat more foods rich in sulfur such as the brassica family (cauliflower, broccoli, onion, garlic, bok choy, etc. Homocysteine depends on these foods to break it down into cysteine which feeds into the methylation cycle. If it is low, it will reach over to glutathione and break it down. This will cause a problem down the road because we need glutathione which is our master antioxidant. Hence, we are depleting that as well.
  3. Poor digestion and absorption of protein. This is where eating hygiene comes into play and is very important to implement. Slowing down when you eat. Chewing your food very well a minimum of 20 times, not consuming water while eating to keep the stomach juices nice and acidic to help break down the food properly. Working on your gastritis and acid reflux if you have any issues because they impact the acidity in your stomach by lowering it.
  4. High demand for glutathione. Inflammation, stress, oxidative stress and free radicals roaming around in the body result in high demand for glutathione to help combat it.
  5. Too much methylation support. Some B complexes contain the active form of B vitamins which are the methylated form. So if you notice that your homocysteine is low, then you may need to reconsider switching to another form of B vitamin that is not the methylated form. This may help raise your homocysteine along with the steps mentioned above.
I will leave you with a few questions to think about as I end this newsletter.
  1. Have you ever checked your homocysteine levels before and will you consider checking them moving forward?
  2. Did your doctor ever explain to you anything about your ranges? Keep in mind the FM optimal RR 5-7 umol/L is much tighter than normal!
  3. Work with a Functional Medicine Practitioner that can help explain things as to why you may not be feeling well or getting better. It may be a methylation issue!
I hope I was able to open your eyes to a marker that is not often tested yet is a window into understanding many health issues such as depression, estrogen dominance, toxicity, CVD, diabetes, etc. that may be at play due to its role in so many biochemical reactions in the body.
I will end the newsletter with my tips for a healthy life
  • One should methylate very well.
  • Sleep is critical for healing, do not abuse it and work on your sleep hygiene.
  • A clean healthy diet is non-negotiable.
  • Movement every day is key.
  • Most importantly you need to reduce your stress levels by focusing on self-care.

Small Changes for a Healthier “U”