Releases energy, keeps red blood cells healthy, makes hormones. High doses of B-2 may help prevent migraine headaches. Sources include: Dairy products, meats, poultry, whole and enriched grains, and green vegetables such as broccoli, turnip greens, asparagus, and spinach. RDA: Between 1.3 to 1.7 mg for adults. Also known as Riboflavin.