Calcium L-5-Methyltetrahydrofolate

Best for

Build nutrient stores in pregnancy

Likely strong benefit · 300–885 mcg/day for 8–52 weeks · 2 meta-analyses , n=1.4k

8 papers · 2 claims · 9 outcomes scored · 2 positive

Outcomes

What calcium l-5-methyltetrahydrofolate actually does, by outcome

Each row is one outcome with effect size, evidence base, the dose that worked in trials, and time to first effect. Magnitude tiers come from native-unit MCID where available, Cohen's d otherwise.

Outcome Effect size Evidence Dose Weeks Rank

Build nutrient stores in pregnancy Likely strong benefit

Tops up the reserves pregnancy drains fastest.

5 meta-analyses n=1.4k 300–885 mcg 8–52 wk #1/4

23543547·27101760·30513795·31138959 +1 more

large

5 meta-analyses n=1.4k Meta-analyzed I²=94%

300–885 mcg

8–52 wk

#1 /4

Lower homocysteine levels Large effect, needs confirmation

Clears a vessel-irritating byproduct that builds when nutrient recycling falls behind.

1 RCT n=73 200 mcg 13 wk #1/12

23698160

large

1 RCT n=73

200 mcg

13 wk

#1 /12

Outcome	Effect	Evidence	Dose	Weeks	Rank
Build nutrient stores in pregnancy Likely strong benefit	large	5 meta-analyses n=1.4k Meta-analyzed	300–885 mcg	8–52 wk	#1/4
Lower homocysteine levels Large effect, needs confirmation	large	1 RCT n=73	200 mcg	13 wk	#1/12

Risk profile

Adverse events and known drug interactions

Safety events

gastrointestinal discomfort (poor digestion / abdominal bloating) moderate

headache mild

treatment-emergent adverse events (overall)

Gastrointestinal disorders

Infections and infestations

General disorders and administration site conditions

Respiratory, thoracic and mediastinal disorders

Nervous system disorders

Sources

Generated August 14, 2026