Nutrients and interactions
Supplements if you take the birth control pill
Older research blamed the pill for low folate, B vitamins, magnesium and zinc, mostly from blood-level comparisons and pills with much more estrogen than today's. A review of the evidence found that with current low-dose pills the case holds up for vitamin B6, not for folate or B12. The bigger practical issue is interactions, because St John's wort and a few other supplements can make the pill fail. This page is about nutrients and interactions: never stop or switch your contraceptive without your prescriber.
This page covers nutrients and supplement interactions. Never stop or change a prescribed medication without your prescriber, and check any new supplement with your pharmacist.
Evidence last reviewed: October 2026
Top picks
| Option | Evidence | Best for | The honest note | |
|---|---|---|---|---|
| Folic Acid (Vitamin B9) | Strong evidence | if pregnancy is possible | Periconceptional folic acid cuts neural tube defects by about 70%, and many unplanned pregnancies begin while women are on the pill. 400–800 mcg a day is the standard dose, even though current pills do not appear to lower folate. | View |
Solid options
| Option | Evidence | Best for | The honest note | |
|---|---|---|---|---|
| Women's Multivitamin | Moderate evidence | folate and B6 in one tablet | Folic acid at 400 mcg is its best-supported ingredient for anyone who could conceive, and its iron helps if you are iron deficient. It covers the B vitamins the pill may affect without megadosing. | View |
Situational
| Option | Evidence | Best for | The honest note | |
|---|---|---|---|---|
| Vitamin B6 (Pyridoxine) | Moderate evidence | a small dose, never megadoses | US survey data found most pill users had plasma B6 (PLP) below 20 nmol/L, and intakes of 3–4.9 mg a day protected against low levels in most groups. A small dose covers this; long-term intake above 50 mg a day is where nerve damage reports start. | View |
Skip, or avoid with this medication
- St John's Wort Strong evidence
It speeds up breakdown of the pill's hormones, causing breakthrough bleeding and documented contraceptive failure, so use another method or do not take it.
- Activated Charcoal Limited evidence
It adsorbs oral contraceptives in the gut and can drop hormone levels below the contraceptive threshold, with no proven benefit for bloating or detox.
- Calcium-D-Glucarate Limited evidence
It is sold as an estrogen detox without a single human trial, and it could speed clearance of the pill's hormones, so clear it with your prescriber first.
- Indole-3-Carbinol (I3C) Limited evidence
It induces liver enzymes and may lower contraceptive hormone levels, and its effect on estrogen ratios is a biomarker with no proven benefit.
- Vitex (Chasteberry) Moderate evidence
Its PMS evidence is real but inflated by manufacturer-linked trials, and it may theoretically reduce contraceptive reliability.
- Detox Tea Blends Limited evidence
Senna-based teas speed gut transit and reduce absorption of oral drugs, including the pill, and they produce no real weight loss.
Our verdict
If pregnancy is possible now or after you stop the pill, take 400 mcg of folic acid a day, for example in a women's multivitamin that also covers B6. Do not take St John's wort, activated charcoal or calcium-D-glucarate while you rely on the pill.