Methylation, Active Folate and Iron Balance
How the folate pathway works, and why active folate and iron go together.
Erdem Bayraktar — Molecular Biology & Genetics Engineer, Üsküdar University4 November 2026, 5-minute read
What MTHFR does
The MTHFR enzyme turns folate into the form the body uses, 5-methyltetrahydrofolate. This active form is needed to convert homocysteine into methionine.
C677T and A1298C are the commonest variants and are widespread in the population. People with two copies of C677T have clearly lower enzyme activity. This is a genetic tendency, not a disease, and a valuable clue for choosing the right form of folate.
What homocysteine shows
Homocysteine is an amino acid formed in the methionine cycle. It can rise when folate, B12 or B6 run short, and high homocysteine is a finding followed for vascular health.
Your genes show your tendency; your measured values show where you stand today. That is why we read your genetic finding together with your homocysteine, folate and B12 values.
Active methylfolate and iron
Methylfolate is the active form of folate and needs no conversion, so it can be preferred in people with an MTHFR variant.
Folate and iron work together in making blood: folate for cell division, iron for haemoglobin. Topping up one while the other is short may not fully correct the picture. But iron should only be taken when it is needed; iron supplements are not suitable when ferritin is high. High-dose folate should not be taken without checking B12 either, because it can mask a deficiency.
