Hi Emily,
I also found this "in-depth report" in the New York Times, an excerpt of which says:
NUTRITION AND DIETARY SUPPLEMENTS
Foods. Good nutrition, while essential for anyone, is critical for patients with sickle cell disease. Some dietary recommendations include:
Fluids are number one in importance. The patient should drink as much water as possible each day to prevent dehydration.
Diet should provide adequate calories, protein, fats, and vitamins and minerals. Patients and families should discuss vitamin and mineral supplements with their doctors and nurses.
Some studies claim that omega-three fatty acids, found in fish and soybean oil as well as dietary supplements, might make red blood cell membranes less fragile and possibly less likely to sickle, although no studies have proven this definitively.
Vitamins. Patients should take daily folic acid and vitamin B12 and B6 supplements. Vitamin B6 may have specific anti-sickling properties. Some doctors recommend 1 mg folic acid, 6 microgram vitamin B12, and 6 mg vitamin B6. Foods containing one or all of these vitamins include meats, oily fish, poultry, whole grains, dried fortified cereals, soybeans, avocados, baked potatoes with skins, watermelon, plantains, bananas, peanuts, and brewer's yeast. Of note, folic acid can mask pernicious anemia, which is caused by deficiency of vitamin B12 and is more common in African-Americans than other populations.
Note on Iron. Although sickle cell disease is often referred to as anemia, patients should avoid iron supplements or iron rich foods when receiving multiple transfusions, which increase the risk for iron-overload.