Betaine (TMG) Dosage: 2.5g for Performance vs. 3-6g for Homocysteine
Educational summary — not medical advice. Dosing above 6g/day, or for homocysteine management specifically, should involve a clinician, especially if you have elevated cholesterol. This statement has not been evaluated by the FDA. This product is not intended to diagnose, treat, cure, or prevent any disease.
The honest answer
Betaine has two distinct dose ranges in the literature, not one. For athletic performance, ~2.5g/day (often split 1.25g twice daily) is the most-used trial dose — and no trial at this dose found a 1RM strength advantage. For homocysteine-lowering, 3-6g/day is the well-replicated range, with 6g/day showing the clearest effect — and the dose where betaine also raises LDL cholesterol. A single 1g dose does nothing measurable; the 20g/day used in one liver trial is a clinical outlier, never a general-consumer target.
Why the dose depends on the question you're asking
Betaine doesn't have one settled "correct" dose — it has two separate research literatures, each pointing to a different range. The performance dose, ~2.5g/day, is what Cholewa et al. 2013 and Cholewa et al. 2018 (the latter with a disclosed DuPont Nutrition & Health funding tie) used in their resistance-training trials, often split into two 1.25g doses per day; Nobari et al. 2021 used a slightly lower 2g/day in adolescent athletes. Across every performance trial in this evidence base that measured 1-rep-max strength, none found a betaine advantage — signal, where present, showed up in power output, endurance reps, or body composition instead. The homocysteine range, 3-6g/day, comes from Olthof et al. 2003 and Schwab et al. 2002; 6g/day is the dose with the clearest, most consistent homocysteine-lowering effect — and the same dose Olthof et al. 2005 found raises LDL cholesterol and triglycerides. These are not interchangeable numbers; picking a dose means picking a use case.
| Reference point | Amount | What it means |
|---|---|---|
| Athletic performance dose | ~2.5g/day | Most-used trial dose (Cholewa 2013/2018; the 2018 trial had a disclosed DuPont funding tie); no trial found a 1RM strength advantage at this dose |
| Homocysteine-lowering range | 3-6g/day | Well-replicated (Olthof 2003, Schwab 2002/2006); 6g/day is clearest but raises LDL cholesterol (Olthof 2005) |
| Acute ineffective dose | 1g single dose | Did NOT lower homocysteine within 2 hours (Schwab 2006) — below the effective threshold |
| 4g/day, 6-month duration | 4g/day, long-term | Schwab 2011: homocysteine-lowering effect "weak," not reliable over 6 months — dose/duration combination matters |
| NASH clinical research dose | 20g/day, 12 months | Abdelmalek 2009 — a diseased-population research dose, still null on the outcomes that mattered; NOT a general-consumer target |
| Reference: Cystadane (prescription) | Well above supplement range | FDA-approved for homocystinuria under medical supervision — evidence betaine reliably lowers homocysteine clinically, not a self-dosing target |
No established Upper Limit — treat the well-studied range as the ceiling, not 20g
Unlike choline, which has a formal 3,500mg/day Tolerable Upper Intake Level, there is no established Upper Limit for betaine. The trial safety record tops out at 20g/day for 12 months in the NASH trial without serious adverse events reported — but that is a safety observation in one small diseased-population trial, not the same thing as an established general-population safety ceiling. The honest frame: 1.5-6g/day is the well-studied range across multiple healthy-adult RCTs; treating "up to 20g is proven safe for healthy people" as a green light overstates what one clinical trial in sick patients actually showed.
Food sources, for context
Betaine occurs naturally in several foods, per Craig 2004: wheat bran and wheat germ and seafood/shellfish run around 1% by weight; spinach is around 0.7%. Beets also contain betaine — it's the compound's namesake — but at a lower, more variable concentration that this evidence pack does not have a specific percentage for. Food-first is a reasonable starting point for general methylation support; supplement doses in the 1.5-6g/day range are what the clinical trials on this page actually tested, well above what typical diets provide.
Picks by dose
Full ranking by cost per gram is on best betaine.
At 6g/day, this powder costs about $0.17/day — one to two scoops.
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Frequently asked questions
How much betaine (TMG) should I take?
~2.5g/day for performance, 3-6g/day for homocysteine — different use cases, different doses.
Does a single 1g dose do anything?
No — Schwab 2006 found 1g did not lower homocysteine, while 3g and 6g did within 2 hours.
Is more betaine always better?
No — 4g/day for 6 months showed a weak, unreliable effect (Schwab 2011), and 6g/day raises LDL cholesterol even as it lowers homocysteine best.
Is the 20g/day NASH dose safe for general use?
Not established for general use — it's a clinical research dose in sick patients that still didn't improve the outcomes that mattered.
Related
- Betaine (TMG): homocysteine and pre-workout, honestly explained
- Best betaine — ranked by cost per gram
- Betaine and homocysteine
- Does betaine work for strength?
Sources
- Olthof MR, et al. "Low dose betaine supplementation leads to immediate and long term lowering of plasma homocysteine in healthy men and women." J Nutr. 2003. PMID: 14652361
- Schwab U, et al. "Orally administered betaine has an acute and dose-dependent effect on serum betaine and plasma homocysteine concentrations in healthy humans." J Nutr. 2006. PMID: 16365055
- Schwab U, et al. "Betaine supplementation decreases plasma homocysteine concentrations but does not affect body weight, body composition, or resting energy expenditure in human subjects." Am J Clin Nutr. 2002. PMID: 12399266
- Olthof MR, et al. "Effect of homocysteine-lowering nutrients on blood lipids: results from four randomised, placebo-controlled studies in healthy humans." PLoS Med. 2005. PMID: 15916468
- Schwab U, et al. "Long-term effect of betaine on risk factors associated with the metabolic syndrome in healthy subjects." Eur J Clin Nutr. 2011. PMID: 20978525
- Craig SA. "Betaine in human nutrition." Am J Clin Nutr. 2004. PMID: 15321791 (food sources).
- Abdelmalek MF, et al. "Betaine for nonalcoholic fatty liver disease: results of a randomized placebo-controlled trial." Hepatology. 2009. PMID: 19824078
- Cholewa JM, et al. "Effects of betaine on body composition, performance, and homocysteine thiolactone." J Int Soc Sports Nutr. 2013. PMID: 23967897
- Cholewa JM, et al. "The effects of chronic betaine supplementation on body composition and performance in collegiate females: a double-blind, randomized, placebo controlled trial." J Int Soc Sports Nutr. 2018. PMID: 30064450 (DuPont Nutrition & Health funding tie disclosed).
- Full product dataset: /betaine-tmg/cost-by-brand.json (CC BY 4.0).