NutriStack
Combined Oral Contraceptive and Methylcobalamin, a synergy.
Methylcobalamin is the active circulating form of vitamin B12 and is depleted along with other B vitamins during combined oral contraceptive use. Restoring B12 is particularly important for one-carbon metabolism, energy, and pre-conception health.
One pair, every claim cited. The two substances, the type, the mechanism, the recommendation, and the primary literature.
Same shape as the other 1,729 pairs in the public database.
From the interaction database
What the row says.
Every entry follows the same shape: what is happening, the mechanism, the recommendation, and the primary literature.
At a glance
- Substances
- Combined Oral Contraceptive and Methylcobalamin
- Pair type
- Synergy
- Evidence (highest tier)
- Moderate
- Source citations
- 2 sources
- Stack Score effect
- +2 to your Stack Score (per scored synergy row).
- Scope
- Supplement × Prescription
- Last verified
- May 30, 2026
Synergy · Moderate evidence
Synergy
What is happening. Methylcobalamin is the active circulating form of vitamin B12 and is depleted along with other B vitamins during combined oral contraceptive use. Restoring B12 is particularly important for one-carbon metabolism, energy, and pre-conception health.
Mechanism. COCs reduce serum total B12 and holotranscobalamin; methylcobalamin directly replenishes the active pool and supports methionine synthase, homocysteine remethylation, and myelin maintenance.
Recommendation. Take methylcobalamin 500-1000 mcg daily while on combined oral contraception, particularly with concurrent methylfolate. Either is best taken in the morning with breakfast.
Sources (2)
- Palmery M, Saraceno A, Vaiarelli A, Carlomagno G. Oral contraceptives and changes in nutritional requirements. Eur Rev Med Pharmacol Sci. 2013;17(13):1804-13. PMID 23852908
- Basciani S, Porcaro G. Counteracting side effects of combined oral contraceptives through the administration of specific micronutrients. Eur Rev Med Pharmacol Sci. 2022;26(13):4846-4862. PMID 35856377
Stack Score
How this pair moves the number.
Effect on the composite score
If both Combined Oral Contraceptive and Methylcobalamin are in the same stack, this pair applies +2 to your Stack Score (per scored synergy row).
The full algorithm, the clamping rules, and four worked stacks are documented at /methodology/stack-score.
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