AStrong evidence, for the people named belowVitamin
The short answer
400 micrograms daily before and in early pregnancy is not optional in the way most supplements are. Outside that, food folate is enough.
Who this is actually for
Anyone who could become pregnant, from before conception through the first twelve weeks. This is one of the clearest preventive measures in medicine.
What it is legally allowed to claim
Quoted from the EU register of authorised health claims, Regulation (EU) 432/2012. A product may only make these claims if it supplies enough of the nutrient to qualify.
- Folate contributes to normal blood formation
- Folate has a role in the process of cell division
How much is too much
EFSA tolerable upper intake level 1000 micrograms per day for adults, set 2023.
Cautions and interactions
High folic acid can mask B12 deficiency. Some anti-epileptic and methotrexate regimens interact, so check with your prescriber.
Ask a pharmacist before you start anything. Interactions with prescribed medicines are the most common way supplements cause harm, and they are easy to check. Bring the actual packet, or a photo of the ingredients panel, because doses and forms vary enormously between products. Nothing here is a substitute for advice about your own situation.