anemia

My son is a very picky eater, he only eats yoghurts for breakfast, dairylea sandwiches for lunch + crisps and cake, and for tea will eat waffle turkey dino's or mashed potato with mac/cheese mixed in, he wont try anything else, he used to eat lots of fruit but only has fits and starts with it, he wont eat any veg at all, even at school they dont seem to give fruit out for snacks anymore it's crackers which he will eat, my concern is that he is always on the go and has the potential of doing well in gymnastics, but always seems to be fighting of a cold, last year he had a year of mood swings and temper tantrums and crying and so i took him to my gp and found he had glandular fever, so we have sat him down and explained to him that unless he starts to eat a bit better then he may always feel this way, but this has had no effect, i just need soom advice on wether to take him back to my gp for tests on eating also i'm, worried that he could be anemic is this common in children with this sort of diet?

[Renee Radenberg]

His weight is between the 50-25th percentile and his height is on the 50th percentile for which indicates he is normal for his age. Suggest giving him daily children's chewable multi-vitamin due to his eating habits.