Value Per Nutrient Food 4.50 mg 100 grams Niacin Beef, brisket, flat half, separable lean and fat, trimmed to 0" fat, choice, cooked, braised 4.49 mg 100 grams Niacin Mushrooms, portabella, raw 4.49 mg 100 grams Niacin Mushrooms, portabella, exposed to ultraviolet light, raw 4.49 mg 100 grams Niacin Candies, REESE'S Peanut Butter Cups 4.49 mg 100 grams Niacin Fish, eel, mixed species, cooked, dry heat 4.49 mg 100 grams Niacin POPEYES, Fried Chicken, Mild, Skin and Breading 4.48 mg 100 grams Niacin Beef, round, tip round, roast, separable lean and fat, trimmed to 0" fat, select, cooked, roasted 4.47 mg 100 grams Niacin Beef, shoulder top blade steak, boneless, separable lean and fat, trimmed to 0" fat, select, cooked, grilled