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Vitamin B3 (Niacin and Metabolite) Blood Test

Vitamin B3 Blood Test assesses the amount of Niacin (Nicotinic Acid) know as Vitamin B3, a water-soluble vitamin in the blood.


Niacin (Nicotinic Acid) is Vitamin B3, a water-soluble vitamin. It occurs naturally in plants and animals, and is also added to many foods as a vitamin supplement. Niacin can lower cholesterol and triglycerides in the blood, and is also used to lower the risk of heart attack in people with high cholesterol who have already had a heart attack.

A deficiency of niacin causes pellagra. The symptoms include:

  • Digestive problems
  • Inflamed skin
  • Mental impairment

Large doses of niacin can cause:

  • Increased blood sugar (glucose) level
  • Liver damage
  • Peptic ulcers
  • Skin rashes


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