Flax seeds could kill you!
Flax seeds are healthy when enjoyed in moderation. 1-2 tbsp a day is considered safe. Flax seeds, especially raw ones, contain substances (e.g. cyanide and cadmium) that could lead to poisoning, in the worst case to death, although according to my research, no cases of fatal poisoning are known. But an average person usually does not eat as many raw flax seeds as one might consume on the raw diet when making breads and crackers using flax seeds. Please be mindful and do your research before consuming any amount of flax seeds.