If he has anemia, he isn't eating very well or he isn't absorbing what he is eating very well. He is also, let me be kind as I am no spring chicken, getting old, and stuff happens. Also, some of those pills docs give out can't be absorbed by human beings very well, so he needs to be tested to make sure he is absorbing them. Some form of iron is just not very well absorbed but is really inexpensive to produce and so more profitable than using better absorbed forms of iron. Doctors are usually clueless about nutrition.