Niacin also is known as vitamin B3, a vitamin necessary to build fatty acids and red blood cells and convert carbohydrates, fats and proteins into energy. While niacin has important functions, it is possible to be allergic to foods that contain it. When you experience an allergic reaction to niacin, your body treats it like a foreign invader, resulting in inflammatory symptoms like a rash, breathing difficulty or itching skin. While the foods listed below do not make up a comprehensive list of niacin-containing foods, they are a representative sample of foods to avoid.
A variety of meat sources have niacin. One example is light-meat turkey, which contains 6 mg of niacin per 3-oz. serving. The same serving size of cooked lean ground beef contains 5 mg of niacin per serving. Fish like salmon also have 7 mg of niacin per 3-oz. serving.
When you take in foods containing tryptophan, your body converts the trytophan into niacin, meaning they could cause you to have an allergic reaction. These foods can have sleep-inducing effects on your body -- one example is the Thanksgiving turkey that makes you feel sleepy after eating. Other tryptophan-containing foods include red meat, eggs and dairy products.
Certain foods are fortified, or have vitamins and minerals added to them, to increase their nutritional value. Niacin is an example of a vitamin often added to fortified foods. Examples include ready-to-eat cereals -- 1 c of cereal contains about 5 mg of niacin. Whole-grain breads also may have niacin added to them -- you may wish to purchase non-enriched or refined-grain breads to avoid niacin.
Other dietary sources of niacin include organic peanuts or peanut butter, which contains about 3.8 mg of niacin per 3-oz. serving. Potatoes also contain niacin -- one medium potato has 2.7 mg per serving. One cup of cooked lentils contains 2.1 mg of niacin, while the same size serving of lima beans has 1.8 mg. Sunflower seeds, beets, brewer's yeast and mushrooms also contain niacin.
Niacin can be difficult to avoid in your daily diet because many foods contain it. However, your physician may recommend eating foods known to contain small amounts of niacin, which may be less likely to cause an allergic reaction in your body. Determining how much niacin you can consume without causing a reaction in your body is an individual process. Some people with a niacin allergy may be able to eat 3 mg at a time while others may not tolerate niacin at all. Work with your physician and keep a food journal recording any reaction you may have to determine your individual tolerance level. Note that excess niacin intake can cause symptoms similar to an allergic reaction, including skin flushing, stomach redness and warmth, particularly of the face. Your physician may recommend allergy testing to determine if you have an allergy or symptoms of excess intake.