Foods high in niacin, also known as vitamin B-3, are fish, chicken, turkey, pork and peanuts. Beef, mushrooms, green peas, sunflower seeds and avocados are also good sources of niacin.
Niacin, or vitamin B-3, is an essential vitamin for the body. Niacin aids in processing body fat, helps lower cholesterol levels and regulates blood sugar. A small deficiency in niacin usually causes symptoms such as anxiety, fatigue, restlessness and depression. The body easily absorbs and regulates niacin, since it is a water-soluble vitamin. However, overdoses can occur, with an overdose generally causing dry skin or flushing of the skin.
Fish contain the most niacin by serving size. Types of fish that are high in vitamin B-3 include yellowfin tuna, wild salmon, mackerel and halibut. With a little less of the vitamin per serving than fish, chicken and turkey are both good sources of it as well. Pork and cooked lamb liver also contain a significant amount of niacin, while oil-roasted peanuts are perhaps the best snack-food source of the vitamin. Types of beef that are good sources of B-3 include cooked lean rib, sirloin steak, beef fillet and tenderloin.
In terms of mushrooms, Portobellos are the best source of niacin.