Umair,
I am sure that Andy will clarify but meat has heme iron which poses the greatest threat to thals, as well as "enriched" foods like certain breads and cereals. Fruits and vegetables, even those considered high in iron do not pose the same risk as the iron they contain is less likely to be absorbed. The benefits that beets and other fruits and veges far outweigh the small amount of iron you are likely to absorb from them. Be sure to get a good assortment of fruits and veges - it is good for your thalassemia and if they can be good for your diabetes too. Eating every 2 hours - which includes having fruits or veges between meals will keep your blood sugar balanced and provide you with antioxidants necessary in combating harm from iron.
Sharmin