I had unexplained anemia in 2009, i understand this is unusual for a male, they put it down to my diet, can that simply be the reason? im worried stil

It's possible: When a man over age 50 develops iron-deficiency anemia, doctors are trained to think about colon cancer, which can cause silent blood loss. But if your anemia went away with a change in your diet, it was probably due to your diet! lack of folate (folic acid) from leafy green vegetables, or lack of vit b12, can also cause anemia. Follow-up with your doc to make sure your anemia has resolved.

Sometimes: However depending on how old you are, a workup from a gastroenterologist is probably warranted.