Primary Causes & Action Plans

Homocysteine

Amino acid that damages neurons and arteries; high levels predict dementia and CVD
Elevated homocysteine damages neuronal membranes, promotes amyloid accumulation, and accelerates atherosclerosis. It is fully correctable with B vitamins.
Target < 10 umol/L
Suggested Action Plan

If elevated, supplement methylfolate (800-1000 mcg), methylcobalamin (1000 mcg), and pyridoxal-5-phosphate (50 mg) daily. Retest in 4-8 weeks.

Vitamin B12

Essential cofactor for homocysteine methylation; deficiency raises homocysteine
B12 is required for the methylation cycle that clears homocysteine. B12 deficiency is the most common cause of elevated homocysteine.
Target > 500 pg/mL
Suggested Action Plan

If low, supplement with methylcobalamin (active form) 1000-2000 mcg daily or 1000 mcg weekly injections. Parenteral injections work better if absorption is impaired.

Folate (B9)

Essential cofactor for methylation; deficiency raises homocysteine
Folate is the primary methyl donor in the methylation cycle. Folate deficiency impairs methylation and elevates homocysteine.
Target > 8 ng/mL
Suggested Action Plan

Supplement with methylfolate (active form) 800-1000 mcg daily. Methylfolate is better absorbed and more effective than folic acid, especially in those with MTHFR variants.

Vitamin B6 (Pyridoxal-5-Phosphate)

Cofactor for homocysteine remethylation; deficiency raises homocysteine
B6 is required for transsulfuration (homocysteine to cysteine conversion). B6 deficiency impairs both methylation and transsulfuration.
Target > 30 ng/mL
Suggested Action Plan

Supplement with pyridoxal-5-phosphate (active form) 50-100 mg daily. Active B6 form is better absorbed than pyridoxine.

MTHFR Genotype

Genetic variants affect methylation capacity; homozygous variants require methylated B vitamins
MTHFR C677T and A1298C variants affect folate metabolism. Those with homozygous or compound variants need methylated (not synthetic) B vitamins.
Target Testing determines genotype
Suggested Action Plan

If you have MTHFR variants, use methylfolate and methylcobalamin (not folic acid or cyanocobalamin). This dramatically improves B vitamin response.

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Getting Started

1
Test Your Methylation Status

Test homocysteine, B12, folate, and B6. Optionally test MTHFR genotype if you don't respond well to standard B vitamins.

2
Use Methylated B Vitamins

If B vitamins are low or homocysteine is high, supplement with methylated forms: methylfolate (not folic acid), methylcobalamin (not cyanocobalamin), and pyridoxal-5-phosphate (not pyridoxine).

3
Add Synergistic Nutrients

Magnesium, zinc, and choline all support methylation. Take comprehensive methylation support supplements alongside individual B vitamins.

4
Increase Dietary Methyl Donors

Eat plenty of methylation-supporting foods: leafy greens (folate), eggs (choline), and organ meats (B12). These supplement supplementation.

5
Retest in 4-8 Weeks

Homocysteine should drop significantly (often by 30-50%) within 4-8 weeks of B vitamin supplementation. Retest to confirm improvement and adjust doses if needed.

Why I built this guide.

"Homocysteine and methylation are highly modifiable. Correct B vitamin deficiency and both improve dramatically."

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