Not yet investigated
What we have so far
Without B12, folate piles up in a form it cannot leave. Giving folic acid then fixes the blood count and lets the neurological damage continue.
This star is on the map because the show intends to take the question apart properly — the trials, how it is actually tested, whether the thing sold is the thing studied. That work is not done yet, and nothing here should be read as a conclusion. When the investigation is published it will appear on this page.