Niacin Deficiency Symptoms and Diet

What Does Niacin do?

Medical doctor

Niacin is a form of vitamin B3, which the body needs to maintain healthy cells. Niacin also helps fats and sugars function properly.

The B vitamins work together to regulate the nervous system and maintain healthy skin, eyes, hair and liver. Niacin deficiency is rare in developed countries, but can be found in people with poor diets, alcoholism and some slow-growing tumors. It was common at the beginning of the 20th century before manufacturers began fortifying cereal and other foods with niacin.

Warning Signs of Deficiency

Niacin, like all B vitamins, is water-soluble. The body doesn't store them, so niacin stores must be replenished by diet. Mild deficiencies of this vital nutrient may cause:

  • Canker sores
  • Fatigue
  • Depression
  • Vomiting
  • Indigestion

Pellegra is a severe deficiency characterized by scaly, cracked skin, diarrhea and dementia. The tongue may also swell and turn bright red.

Food Sources

Good food sources for niacin include:

  • Meat
  • Tuna
  • Salmon
  • Peanuts
  • Milk
  • Yeast
  • Eggs
  • Green vegetables
  • Beans
  • Cereals.

Tryptophan is an amino acid that the body converts into niacin, which can be found in red meat, poultry, and dairy products. The recommended daily allowance (RDA) for adults is 12-16 mg. As examples, a 3-ounce serving of chicken has 7.3 mg of niacin. One ounce of peanuts has 3.8 mg; and 3 ounces of lean beef has 3.1 mg. Fortified cereals are the highest, containing 20-27 mg, so vegetarians have many meatless choices that are high in niacin.

Other Benefits

Very high doses of niacin may lower blood triglycerides and raise HDL (good) cholesterol better than some prescription drugs. This may help prevent atherosclerosis (hardening of the arteries). Niacin may also lower the risk of Alzheimer's. Osteoarthritis symptoms may improve, resulting in less pain and greater joint mobility.

Side Effects and Warnings

It is preferable to get niacin from a healthy diet. Very high doses and self-treatment with over-the-counter supplements may result in flushing, headache, blurred vision and dizziness. The risk of liver damage increases, and with patients who have type 2 diabetes, blood sugar levels can increase.

Many drugs can cause interactions with niacin supplements. The blood-thinning effects of coumadin can increase and cause bleeding. Blood pressure medications when combined with niacin may cause low blood pressure. Tetracycline, an antibiotic that is often used to treat acne, may not be absorbed as well and lose it effectiveness. Niacin and other vitamin B complex supplements should never be taken with tetracycline. Zocor, used to treat high cholesterol, may cause muscle inflammation or liver damage when taken with niacin.

Never take supplemental niacin, or any other vitamin or herb product without consulting your healthcare provider. He should be familiar with your complete medical history and all medications you currently take in order to avoid adverse drug reactions.