Supplements
betaine decreases homocysteine
📅 Last reviewed: 2026-07-15 ⓘ
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: All trials, pooled (Meta-analysis)
How the studies fall
What the evidence shows
Betaine (TMG) lowers homocysteine via the BHMT pathway.
The evidence (6)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| d10-3390-antiox15070807 2026 · Antioxidants | animal | supports | moderate | Mice with high-methionine-diet-induced hyperhomocysteinemia given betaine supplementation for 14 days showed attenuated hHcy-induced cognitive impairment via reduced oxidative stress/PI3K-AKT-GSK3b pathway; betaine 'known to reduce Hcy leve |
| McRae 2013 · J Chiropr Med | meta-analysis | supports | moderate | MA of RCTs: 6 g/d betaine lowers plasma homocysteine 5-20% in healthy adults |
| Zhang 2026 · Nutr Hosp | RCT | supports | moderate | Betaine-containing nutrients reduced Hcy more than B6/B12/folate control in overweight HHcy patients |
| Lu 2023 · Eur J Nutr | RCT | supports | moderate | Low-dose B-vitamins plus betaine reduced plasma homocysteine in adults with hyperhomocysteinemia |
| betaine-meta-2021 2021 | meta-analysis | supports | moderate | Betaine >=4g/d lowers Hcy but raises total cholesterol +0.34 mmol/L. |
| Çakır Gündoğdu A et al 2022 · study_type: animal | animal | supports | moderate | Wistar rats given oral betaine 250 mg/kg for 21 days before ethanol-induced gastric ulcer showed significantly reduced homocysteine levels vs vehicle. Also improved oxidative-stress markers (TOS, MDA down; TAS, GSH, CAT up). |
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