I've no idea how much Niacin is added in America, but you can have too much. Since we don't eat much corn here in Europe, packing food unnecessarily full of this supplement could be dangerous to health:
Niacin Toxicity
Symptoms of toxicity include: Flushing of the skin, primarily on the face, arms, and chest *This side effect may occur at doses as low as 30 mg/day. Itching. Nausea. Vomiting.
I'm really not sure where that citation is coming from. It's a Google web answer but the source has no citation. Wikipedia lists a textbook, rather than anything from NCBI, and I'm too lazy to dig further. A corn torilla or slice of bread in the US typically has 1-2 mg of niacin, and a daily recommendation of around 16mg.
3 oz (85 grams) of "Chicken breast, meat only, grilled" contains 10.3 grams of the stuff[1], and average adults get about 30mg/day. Best I can tell this is about nicotinic acid specifically, and might be IV rather than ingestion, which is very much an apples and oranges situation.
Agree, I didn't dig - was the first result I found.
Fact is though, that here in Europe there is no need or value in adding this supplement, and generally the EU is wary of any adulterated foods without reason.
Niacin Toxicity
Symptoms of toxicity include: Flushing of the skin, primarily on the face, arms, and chest *This side effect may occur at doses as low as 30 mg/day. Itching. Nausea. Vomiting.