I think her overall love of fruit and vegetables is a very good trait and should always be encouraged. There is very little one can do to treat HbH disease and normally the only recommendation is folic acid. The vitamins and minerals in her diet seem to agree with her system and are helping to maximize her health. I doubt the HbF would increase in alpha thal because HbF is the result of alpha and gamma globins, and since no beta thal is present and the production of beta globin is normal, the gamma globin would have little if any significance. If somehow, more alpha globin is being produced because of these foods, it would combine with the beta globin already present, and create normal hemoglobin. It does seem that many fruits have blood building properties and even have an effect on iron deficient anemia, even without having high iron concentrations. As with wheatgrass, the mechanisms of how they work, are not really known. My view is, if it works, keep doing it.