Comment by hansvm

Anti-folates (similarly with magnesium and a few other things) are closer to chemotherapy than anything else. They promote cancers because they promote nearly every human cell, and the logic behind removing them is that since cancer cells divide so comparatively rapidly they'll be selectively targeted by a lack of division-enabling nutrients. Most people absolutely shouldn't be restricting their folate intake.

If we take your claim to its logical conclusion (that we shouldn't add those vitamins and minerals to our foods because they might hurt a small percentage of people), the other side of the coin is that we should _remove_ extra vitamins and minerals. If we don't, we're just implicitly medicating a whole population rather than proactively medicating them. Peanuts hurt some people; let's ban them everywhere. End-stage kidney patients without full renal failure often can't tolerate salt or phosphorus; let's not salt any of our food and ban the sale of eggs and meats. Diabetics can't easily tolerate a high glycemic load; let's be extra safe and not use any sugars or alcohols.

Or...make reasonable population-level interventions and let people with special needs handle their own special needs. There are gluten-free breads, no-excess-folate flours, and all sorts of things on the market.

While we're talking about baseline levels of B vitamins (folate), did you know that most bakers are also dumping a rich, broad-spectrum source of most B vitamins and trace minerals into your bread? It's not just folate. They then let that yeast further multiply for 2hr+ just to bump the vitamin levels up (or, worse, add extra yeast at the start to speed up the baking cycle).