The Short Answer: MTHFR is an enzyme that helps your body process folate, a B vitamin essential for detoxification, brain health, and immune function. About 60% of people have a MTHFR gene variant that can impair methylation, a critical metabolic process. If you have an autoimmune condition or struggle with brain fog, fatigue, or mood issues, understanding your MTHFR status can help you optimize supplementation and manage symptoms more effectively.

Understanding MTHFR and Methylation

MTHFR stands for methylenetetrahydrofolate reductase. This enzyme helps your body process folate (a B vitamin) so it can actually use it. You also need MTHFR to process folic acid, a synthetic form of folate found in supplements and fortified foods.

Methylation is a process of adding a methyl group to molecules throughout your body. This vital biochemical process governs detoxification, hormone metabolism, immune function, and countless other essential metabolic pathways. When methylation isn’t working properly—often because of an MTHFR gene variant—your whole system can struggle.

About 60% of people carry at least one MTHFR gene variant. If you have one, it means your methylation pathways may not be working at full capacity. This becomes especially important if you’re managing an autoimmune condition like Hashimoto’s low thyroid, lupus, or rheumatoid arthritis, or if you’re dealing with brain-based symptoms like fatigue, brain fog, or depression.

What Methylation Actually Does in Your Body

Appropriate methylation is involved in nearly every major metabolic function. Here’s what depends on it:

• Turning genes on and off
• Detoxifying chemicals, toxins, and heavy metals from the body
• Building brain neurotransmitters like serotonin and dopamine
• Metabolizing and clearing excess hormones
• Building and regulating immune cells
• Synthesizing DNA and RNA
• Creating cellular energy (ATP)
• Producing myelin, the protective coating around nerves
• Metabolizing histamine and other inflammatory molecules
• Supporting eye health and vision
• Regulating fat metabolism
• Supporting liver and kidney detoxification

When methylation works efficiently, you can make proteins, utilize antioxidants, clear excess hormones, balance brain chemistry, and dampen inflammation. All of these are critical for managing autoimmune conditions and brain health.

MTHFR Defects and Their Health Impact

The inability to process folate efficiently can result in elevated levels of homocysteine, an amino acid that increases the risk of heart disease and cognitive decline when too high.

Inadequate methylation also impairs your body’s ability to produce glutathione, your primary cellular antioxidant. When glutathione becomes depleted, your risk of developing autoimmune diseases, food sensitivities, and chemical sensitivities increases significantly.

An MTHFR variant also impacts the brain’s ability to manufacture vital neurotransmitters. This is why MTHFR defects have been linked to depression, anxiety, ADHD, brain fog, bipolar disorder, and other mood and cognitive issues.

MTHFR variants have been associated with increased risk of:

• Heart disease and stroke
• Venous thrombosis
• Cancer
• Birth defects
• Inflammatory bowel disease
• Autoimmune disorders, including Hashimoto’s low thyroid
• Mental and mood disorders

Testing and Managing MTHFR

You can test for MTHFR gene variants through companies like Spectracell or 23andme.com. For interpretation, use geneticgenie.org.

The two most common problematic variants are 677 and 1298. However, it’s important to know that just because a variant shows up on a genetic test doesn’t mean it’s actively causing problems; gene expression depends on many factors.

To support methylation pathways if you have an MTHFR variant:

• Take methylfolate (not folic acid) as a supplement
• Use methylcobalamin (methyl B12) instead of standard cyanocobalamin
• Add a high-quality liposomal glutathione supplement
• Reduce your exposure to toxins, pesticides, and environmental chemicals

These same strategies benefit anyone managing autoimmune conditions or brain-based symptoms, whether or not they have an MTHFR variant.

Contact RedRiver Health and Wellness to work with a functional medicine doctor who can evaluate your methylation status and optimize your nutrient protocol for autoimmune and brain health.