Turkey and milk are particularly excellent sources of tryptophan. When used as therapy for a specific disease, niacin, niacinamide, and inositol hexaniacinate are taken in dosages much higher than nutritional needs, about 1 to 4 g daily. Because of the risk of liver inflammation at these doses, medical supervision is essential. For prevention of diabetes in children, the usual dosage of niacinamide is 25 mg per kilogram body weight per day. There are 2.2 pounds in a kilogram, so a 40-pound child would get about 450 mg daily.
Many people experience an unpleasant flushing sensation and headache when they take niacin.
These symptoms can usually be reduced by gradually increasing the dosage over several weeks or by using slow-release niacin. However, slow-release niacin appears to be more likely to cause liver inflammation than other forms. Inositol hexaniacinate may also cause less flushing than plain niacin, and if you take an aspirin along with niacin, the flushing reaction will usually decrease. Niacinamide may improve blood sugar control in both children and adults who already have diabetes. For other treatments that may help intermittent claudication, see the articles on carnitine and ginkgo .