Methyl tetrahydrofolate Reductase (MTHFR): The Thyroid Connection

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Pollutants, poor nutrition, and stress, are putting increased demands on methylation processes, as the body works to preserve itself. When a MTHFR variation is present, as it is in almost half the population, the ability to methylate is hindered, increasing health risks. Expert Dr. Ben Lynch has linked the genetic variation, known as a “SNP” (single nucleotide polymorphism), to over sixty conditions. Some are related to how you think and feel, while others are more serious, i.e. heart disease, dementia, and cancer. There are also individuals that have the MTHFR SNP and don’t experience any noticeable symptoms.

Why is this topic important?

MTHFR information can be helpful to target nutritional and lifestyle protocols when struggling with a difficult condition, such as thyroid dysfunction. In other words, nutrition and lifestyle support can be used to offset deficiencies and restore balance. Even without the genetic SNP, having low thyroid hormone levels contributes to diminished MTHFR function. Although it’s a small piece of the puzzle, it could be a big step towards better health, as well as explaining metabolic anomalies.

What is MTHFR?

Methyl tetrahydrofolate reductase (MTHFR) is the name of both the gene and the enzyme that the gene produces. The enzyme is used to convert folic acid and folate into a form that the body can use, i.e. methylfolate, which is important for numerous biological processes. Your MTHFR composition is dependent upon the two genes from your parents. Depending on whether you inherited zero, one or two MTHFR SNPs (pronounced “snips”), functioning may be reduced by as much as 30 or 70 percent. Methylation is also required for:

  • Repairing damaged cells, as well as ensuring optimal protein and DNA cell function.
  • Coenzyme Q10, creatine, melatonin, phosphatidylcholine and carnitine synthesis. Since mitochondria depend on these compounds, energy and immune processes are also impacted.
  • Glutathione, the body’s primary antioxidant.
  • Metabolizing (breaking down) chemicals and toxins.
  • Metabolizing B-vitamins, neurotransmitters, and hormones.
  • Regulating dopamine, serotonin, and norepinephrine, which influence sleep, behavior and cognitive abilities.

Detoxification and Thyroid

Glutathione, methylation and folate are all integrated cycles associated with MTHFR function, and are also linked to thyroid related conditions. Glutathione is the most abundant detoxifier in the body. It keeps inflammation low, acting as armor against disease processes. Individuals with MTHFR mutations are more vulnerable to stress, toxins, and illness, due to diminished glutathione levels. Research studies show a direct correlation between a breakdown in the glutathione system and autoimmune disease, such as Hashimoto’s. Autoimmune disease is linked to leaky gut, yet in order to have a healthy gut, maintenance of glutathione levels is necessary.

Methylation, B-Vitamins and Thyroid

Nutritional and pharmaceutical recommendations are generally based on the assumption that all systems are functioning at optimal levels. The topic of MTHFR is a good example of how this thinking can falter, and why some people are more sensitive. Folate, B6 and B12 are revered as the most important vitamin “co-factors” in the methylation process, however, riboflavin also plays a key role. Let’s look at how it all fits together:

Folate: Folic acid is the synthetic form of folate used to fortify foods, yet it requires MTHFR for the conversion to a useable form. With the abundance of folic acid in processed foods and vitamin supplements, some are concerned. Without MTHFR, folic acid can pile up potentially resulting in the following:

  • Masking a B12 deficiency. As a result, consequences of low B12 (energy, nerve and brain functions) continue to go untreated, and causing anemia.
  • B12 deficiency is found in approximately 40% of hypothyroid patients.
  • Low B12 also means build up of homocysteine, which is an amino acid that needs B12 to convert it to methionine.
  • Homocysteine is a marker for inflammation such that high levels are associated with high risk of disease, i.e. thyroid disorders and cardiovascular disease.
  • Impaired methylation and high homocysteine negatively affect production of glutathione. Inflammation and oxidative stress are increased under these conditions.

Riboflavin: Riboflavin (vitamin B2) is a cofactor in the conversion of MTHFR. First, the body must convert riboflavin to its useable form, FAD, and the thyroid hormone thyroxine is necessary for this to occur.

Thyroid: Thyroxine (T4) is the hormone the thyroid releases into the bloodstream, where it travels to organs such as the liver and kidneys. The hormone then converts to its active form, T3, which is used by the cells. Thyroxine has important roles in digestion, brain, heart, muscle and bone health, making it one of the most important hormones we have. The body is designed to tightly regulate levels of thyroxine in the bloodstream. However, it often becomes derailed and conditions such as hyperthyroidism (overactive thyroid) or hypothyroidism (underactive) can result. When thyroxine is low, less is available to convert riboflavin, to a form needed for MTHFR. Therefore, folate metabolism, methylation, and everything within its sphere of influence is affected. Should defective MTHFR functioning exist due to a genetic mutation, the consequences may potentially be exaggerated further.

What To Do

Since MTHFR is only one type of gene that makes up your unique profile, it’s important to work with a qualified health professional to see how it may be relevant to you. In the meantime here are some tips:

  • Get tested. Your physician can include MTHFR testing as part of your blood work. Independent labs are also available where a test can be ordered directly.
  • Minimize exposure to chemicals, both internal (food/drink) and external.
  • Supporting detoxification with nutrition and supplements, i.e. hydroxy-B12, magnesium, NAC, milk thistle, and curcumin.
  • Stop taking synthetic folic acid supplements and processed foods fortified with folic acid. Replace them with L-methylfolate or 5-MTHF (although this isn’t optimal for everyone).
  • Foods with natural folate include: asparagus, broccoli, peaches, avocado, spinach, garlic, squash, and grapefruit. Broccoli, cauliflower, and cabbage, help replenish glutathione stores.
  • Optimize gut health. Twenty percent of thyroid hormone conversion occurs in the gut.

Despite the wealth of research pertaining to MTHFR and the biological impacts touched on here, the information is considered new and controversial in mainstream medicine. Many physicians downplay its role in health and disease. If you are struggling with thyroid disorders or suspect MTHFR is affecting you, it is important to seek out a supportive healthcare professional that is open to addressing your needs.

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