Food can cause migraines as that was my trigger---- ingredients such as artificial sugar for example. But i will tell you that food poisening is absolutely accompanied by a horrible headache and vomiting. He can see a doctor for either of these. But his weight shouldn't be a factor unless he is having a heart attack or the precurser for such (which his weight would be a risk factor). So, I'd have him see a doctor. good luck
He would need to see a doctor. If he is getting migraines that often and it's accompanied by vomiting and nosebleeds then there is most likely something going on. Chicken not being cooked well enough, wouldn't cause that.