The Supplement Most People Take Wrong
MTHFR + folic acid. 40% of people have this variant.
The 30-Second Version
Duration: 35 seconds Compliance: "MTHFR," "folic acid," "methylfolate" are all fine - these are supplement/genetic terms, not drugs.
"40% of people have a genetic variant that makes the most common form of vitamin B9 basically useless.
It's in your multivitamin. It's in fortified bread. It's in most prenatals.
If you have this variant, your body can't convert it. And the unconverted form can actually block the receptor that real folate needs.
Check your supplement label right now. Does it say 'folic acid' or 'methylfolate'?
If it says folic acid and you've never been tested - you might be wasting your money. There's a better form available.
I work with a medical team. This was one of the first things we changed based on my genetics.
Simple swap. Huge difference. Link in bio for how to check."
Last line (quotable): "Simple swap. Huge difference."
~40% of people have a genetic variant that makes folic acid significantly less effective — and they have no idea.
It's called MTHFR. Your doctor probably hasn't tested for it.
Here's what you need to know. 🧵
Your body needs folate (vitamin B9) for:
- DNA repair
- Neurotransmitter production (serotonin, dopamine)
- Detoxification
- Cellular energy
Most supplements and fortified foods use FOLIC ACID - the synthetic form.
To use folic acid, your body must convert it using the MTHFR enzyme.
If you have the common variant (C677T or A1298C):
- One copy: ~35% reduced conversion
- Two copies: ~70% reduced conversion
That unprocessed folic acid can actually BLOCK the receptors that real folate needs.
I have compound heterozygous MTHFR (one copy of each variant).
For years I took a standard multivitamin with folic acid. It wasn't helping. It may have been making things worse.
Switched to methylfolate (the pre-converted form) and the difference was noticeable within weeks.
How to know if this affects you:
- Get MTHFR tested (23andMe raw data has it, or ask your doctor)
- Check your supplements - does the label say "folic acid" or "methylfolate" (5-MTHF)?
- If you're pregnant or planning: this is CRITICAL. Talk to your OB about methylfolate vs folic acid.
This isn't fringe science. MTHFR is one of the most studied genetic variants in medicine.
40% of people have at least one copy. It takes 30 seconds to check your supplement label.
Swap folic acid → methylfolate. That's it.
Might be the highest-ROI health change you make this year.
This is what I put in The Manual every week.
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