Methylation is a biochemical process happening in each of our cells thousands of times a minute – just one of the amazing but invisible processes going on in our bodies right now. It’s worth talking about because it plays a big role in mood, stress tolerance and a few other important cellular reactions.
Methylation is critical for the production and release of neurotransmitters that help to promote a balanced mood and a healthy stress response. Methylation is also involved in detoxification, antioxidant production, normal DNA replication, cellular energy production and regulating circadian rhythms to name just some of the important roles in the body that it is involved in.
Folate, vitamin B2, vitamin B6, vitamin B12, zinc, magnesium and various amino acids derived from animal protein are very important nutritional co-factors that need to be in the body in adequate levels in order for methylation to work efficiently.
The causes of impaired methylation
Methylation can become impaired for many reasons and your diet, genes and digestive health can play a big role in this. Here are the main causes.
• Low intake of folate rich foods
A diet lacking in folate rich foods is becoming more common. Many people just do not eat enough uncooked leafy green vegetables in their daily diet. Folate is crucial for the methylation cycle to work properly. For individuals with the MTHFR gene, polymorphism it is important to avoid large doses of synthetic folic acid found in nutritional supplements and commercially-baked products that use folic acid fortified foods. These individuals struggle to convert folic acid to the active form of folate that gets the methylation cycle working efficiently.
• Low vitamin B2 intake
Vitamin B2 or riboflavin is a co-factor for the MTHFR enzyme to help with the conversion to active folate. Vitamin B2 is also a co-factor for methionine synthase reductase (MTRR) enzyme which is catalysed by methionine synthase (MTR) and important for the generation of methyl donors, methionine and S-adenosylmethionine (SAMe).
Vitamin B2 also plays a role in the function of an enzyme called glutathione reductase which regenerates the boy’s most abundant antioxidant, glutathione. Glutathione is also produced as a part of the methylation cycle. People that follow a long term dairy-free diet are at risk of deficiency in riboflavin.
• Inadequate intake of vitamin B12
We need good levels of vitamin B12 to methylate properly. When we don’t eat enough red meat or are eating a vegan or vegetarian diet we are at risk of slowing down methylation. Some people can eat adequate amounts of vitamin B12 containing foods and still have trouble with utilising the vitamin B12 they eat because they have gene polymorphisms for the MTR and MTRR genes. This means they are slow to take vitamin B12 out of the blood and up into cells where it can be used for methylation to occur.
• Low intake of B6 rich foods
Vitamin B6 deficiency comes about mostly because of inadequate intake of whole grains. It is becoming more common to see this with the popularity of grain-free diets like the Paleo and GAPS diet. Vitamin B6 is involved in the conversion of folic acid to active folate and is also involved in the conversion of homocysteine to cysteine via the transulfiuration pathway, a CBS gene dependent process.
• High Homocysteine blood levels
Homocysteine is an amino acid and high levels in the body increase the risk of heart attack and stroke. High levels can damage arterial walls and cause clot formation. Homocysteine is important in the methylation cycle to help with regenerating methionine, another amino acid that is important for donating a methyl group so cellular reactions can happen. Being a smoker, drinking caffeine and consuming too much alcohol all increase homocysteine levels.
• Having the MTHFR genetic polymorphism
Having the MTHFR gene mutation means methylation can be impaired by 25 to 70%. It is an enzyme responsible for conversion of folic acid to the active form of folate.
• Low stomach acid production and damage to the small intestinal lining
We need an acidic environment in the stomach to ensure we adequately breakdown, absorb and assimilate our methylation co-factors. It is in the small intestine that the absorption of nutrients occurs. People with leaky gut, small intestinal bacterial overgrowth (SIBO), fructose malabsorption, Giardia spp. (parasitic) infection or Coeliac disease that has not been properly treated are all at risk of not absorbing their nutrients in the small intestine. This leads to nutrient deficiencies that impair methylation over time.
• Certain medications
There are some medications that impair methylation by affecting folate and vitamin B12 levels in the body. Some drugs such as carbamazepine, asmethotrexate, sulfasalazine, proton pump inhibitors, bactrim and the oral contraceptive pill act as folate antagonists. Nitrous oxide and metformin deplete vitamin B12 levels and cholestyramine depletes vitamin B12 and reduces absorption of folate.