MTHFR: what it means for your health

1 March 2026

Ok so some of you may be thinking it sounds a little like a swear word… others are nodding their heads knowingly and feeling smug.

MTHFR actually stands for METHYLENE-TETRAHYDROFOLATE REDUCTASE gene! Simple right?

The MTHFR gene provides instructions for the MTHFR enzyme (with the same long name above that I love saying- its kind of like supercalifrag.. oh never mind) that converts the folate you eat into the active form that your body can use. So if you have the MTHFR mutation on the gene then you have a problem making the enzyme that converts folate.

So what? Why is folate important I hear you ask?

Because….It is a crucial part of methylation. If the gene is altered (mutated) then the enzyme won't work properly or do its job properly.

But before we get to that….

There are actually over 30 genes that encode for MTHFR but we typically look at just two main genes – MTHFR C677T and A1298C.

If you have had (or are thinking of getting) your MTHFR blood test done you will see that it will state whether you are Heterozygous which means you have 1 copy of the gene from mum OR dad. Or Homozygous where you have 2 copies of the gene from both mum AND dad. OR compound heterozygous/homozygous with one of each.

To give you some idea of how much the gene downregulates function:

Gene VariantZygosityLoss of Function
MTHFR C677THeterozygous30-40%
MTHFR C677THomozygous60-70%
MTHFR A1298CHeterozygous20-30%
MTHFR A1298CHomozygous40%

What do they mean?

People with this copying error on MTHFR C677T are more likely to have elevated homocysteine levels and when you look at family history this may present with a strong trend towards Cardiovascular Disease – stroke, heart attack, deep vein thrombosis.

Those with MTHFR A1298C are more likely to present with neurotransmitter disturbances. In fact approximately 80% of these have a family history of anxiety, bipolar or depression.

In the last 5 years there have been about 5000 papers written on A1298C so that gives you some idea as to it's importance, even IF the pathology labs and doctors poo poo it still.

What we do know is that your genetic makeup cannot change but your EPIGENETICS can. Epigenetics involve the way the environment impact the molecules in your body which can then impact your genes. Which means that diet and lifestyle choices can have a huge impact on how you express those genes.

When you realize that our genes only account for 10% of disease and the exposome (our environment) account for 90% of that gene expression it is hugely important. (BLOG COMING)

Methylation is a dominant factor in epigenetic processes.

MTHFR is a key aspect of methylation – So…


What is Methylation?

Methylation is essential to our physical, mental and emotional wellbeing, for the proper functioning of every body system and actually happens billions of time a second in our cells. It helps repair our DNA, keeps inflammation in check, detoxifies and helps us keep a stable mood. These are just the main things, it is as important to us as breathing.

Bear with me because this is where it gets a bit sciencey.

Methylation is the transfer of a methyl group (one carbon atom and 3 hydrogen atoms) onto amino acids, proteins, enzymes and DNA in every cell and tissue.

BASICALLY Methyl groups act like the ON + OFF SWITCHES of each cell. This means that certain genetic predispositions will either be expressed or not expressed – this is termed GENE EXPRESSION. This is extremely important when you think about genetic predispositions towards say cancer, or schizophrenia for example.

What about DNA replication during conception? That's a huge one… especially when you start to explore the role of folate and Spina bifida. So we really want to optimize our ability to methylate effectively to minimize the chances of issues occurring.

Remember… all healing occurs within a cell – when a cell and its membrane are healthy the other tissues and organs function properly.


What does Methylation do?

Well a lot of very important things like…

  • Turns genes on and off
  • Repairs and builds DNA & RNA
  • Reduces the ageing process (protects telomeres)
  • Detoxifies chemicals & heavy metals
  • Processes hormones
  • Builds immune cells
  • Turns the stress response on and off
  • Provides us with energy
  • Reduces histamine
  • Repairs cell membranes and produces myelination of nerves
  • Supports neurotransmitters to prevent depression, anxiety, insomnia and help brain function

Some of the conditions we know are associated with Under-Methylation are:

ADD/ADHD, Addictive Behaviour, Allergic conditions, Ageing, Anorexia, Alzheimer's Disease, Anxiety, Asthma, Autism, Autoimmune disease, Bipolar, Bulimia, Cancer, Chronic degenerative diseases, Cardiovascular disease, Chronic fatigue, Cleft palate, Diabetes, Down's Syndrome, Delusions, Depression, Poor detoxification, Fatigue, Fibromyalgia, Headaches, Infertility, Joint stiffness/pain/swelling, Insomnia, Muscle pains, Low neurotransmitters, Obesity, Obsessive compulsive disease, Oppositional defiant disorder, Pain, Phobias, PCOS, Psychosis, Schizophrenia, Recurrent pregnancy loss/miscarriage, Thyroid dysfunction.


What affects Methylation?

The things that affect methylation are things like Stress, environmental chemicals (BPA, pollutions, Heavy metals), Medications (antacids, chemotherapy), diet, alcohol, excessive exercise and ageing.

As well as the MTHFR gene there are other genes involved in the methylation pathway and you should not necessarily start with taking methylfolate (active B9) straight away as your body may have other issues in that may need to be addressed first – things like inflammation or hormonal imbalances. Plus taking methylfolate may not be beneficial for some people and actually make them feel worse.


What can I do?

It is a good idea though to keep your toxic load low as you will lack the ability to detoxify properly. So avoiding harsh chemicals, eating organically as much as possible, using chemical free personal care products, exercise regularly (the right sort to minimize inflammation), dry skin brushing, improve gut health and digestion, avoid folic acid supplemented foods (breads and flours) are good places to start.


How do I find out if I have it?

You can be tested through a simple blood test via a referral through either a Naturopath or GP. Bear in mind that many GP's do not know or understand the importance of MTHFR testing. The single test is not covered by Medicare and costs between $50-75.

The other option is to do saliva testing via our functional pathology laboratory for the single test or as part of a comprehensive genetic testing panel which can show you how your own methylation cycle is functioning.


What about supplementation?

So what do you do if you find out you have this MTHFR gene? Which supplements do you need and how much, do I need to change my diet? Well the short answer is it is like everything Naturopathic… its INDIVIDUAL. There is no one size fits all. The best thing is to get tested first and come into see me so I can tailor an individual program or refer you if neccessary.

With regards to supplementation you may need methyl-folate (active B9) or active B12 in the form of methyl-cobalamin or hydroxycobalamin. Perhaps you need SAMe. But then again you may not need to do that straight away depending on the picture – again it is highly individual. The best thing to do is get the simple blood test first. Educate yourself as much as you can. There are links at the bottom of the page as well for you to do more individual research.

Here is a direct quote from Ben Lynch one of the world experts of MTHFR:

"Many people are asking me what protocol they need to be on for each type of mutation. It doesn't work that way. It is not possible nor ethical to tell people that there is a set protocol for each specific MTHFR mutation – or any mutation for that matter. Keep in mind that there are 1,000's of genes in your body and they all are performing certain functions. We cannot simply focus on one protocol for one gene without thinking how the other genes may interact with it."


What about Folic Acid Supplements?

If you have the MTHFR mutation you should be trying to avoid folic acid… why?

The problem with taking folic acid supplements are they are synthetic and not in a form that your body can use. Folic Acid needs to be converted to its active form first. But unfortunately our folate receptors actually prefer to bind to this inactive form of folic acid first and block the real beneficial folate from the foods we are eating binding to them. Studies have shown that this then becomes unmetabolized folic acid – a small amount of which per day does not seem to be a problem eg. 100-200mcg/day. But when high dose supplementation of over 400 mcg occurs it can affect methylation.

One cell this has been proven to affect are sperm cells (which are easy to study as single cell organism that is relatively simple to get hold of). One study showed sperm cells suffered a global loss of methylation after high dose folic acid supplementation. This is an issue because if there is a problem with DNA transcription in a sperm that then reaches an egg and fertilizes it then it is possible there may be birth defects or even problems with conception or multiple miscarriages could occur.

The problem we are finding is that there is now folic acid fortification occurring in many breads, flours and grain products so it is becoming impossible to keep track of how much synthetic folic acid an individual is consuming if they eat these foods. Different countries may have different Public Health supplementation programs going on too.

In clinic I tend to recommend eating lots of natural folate in the form of GREEN LEAFY VEGETABLES plus folinic acid if needed as it is metabolically active. Recently the TGA approved Methyl-folate and many practitioners jumped on the bandwagon of prescribing this form of active folate.

The problem is that if your methylation pathway is not working properly (common in many of us) taking methyl-folate can actually be detrimental. Amazing I know that a simple B vitamin can affect you but it can even make people feel depressed and suicidal. So if you are prescribed this form of folate please keep this in mind. The antidote is Niacin. Email us if you need more info.


Folate pathway deficiency

Some of the symptoms of folate pathway deficiency are allergy, hay fever, hives, multiple miscarriage, depression, anxiety, alcoholism, not hungry in the morning, chronic fatigue (started with glandular fever), high cholesterol, high blood pressure, varicose veins. A family history of cancer especially colon and breast cancer, people who have never been able to tolerate b-vitamins, or the Pill, a deficiency of the fat soluble vitamins A, D, E or K, have memory issues or have never been able to lose weight can have this pathway deficiency as well.


And finally…

So you can see that MTHFR and Methylation can be a complicated thing to understand. It can be even more complicated to treat by yourself. Have a look at the resources and websites below to find out more. You could become one skilled MTHF'R!!

Call me any day on 0438 394069 or book online for an appointment.

Thank you for reading

Stay Well!

Fin Mackenzie Naturopath & Clinic Director Green Door Health Suite 7/16 Waratah Street, Mona Vale NSW 2103


Resources

Also on this site