Niacin

Common Name(s)

vitamin B3, niacin, nicotinamide, niacinamide, nicotinic acid

Scientific Name(s)

3- pyridinecarboxylic acid

General Information

Niacin can be found in foods such as yeast, beans, fish, meat, green vegetables, cereal grains, milk, and eggs. When taken in large amounts, niacin gets converted to niacinamide in the body. Niacin is required for the normal function of sugars and fats in the body and to maintain healthy cells. It is sometimes used as a treatment option for high cholesterol.

How is this product usually used?

Niacin is found in dietary sources and in supplements. It is available in capsules, tablets, chewable tablets and gummies, powders, strips, and liquids. Typical oral doses per day based on age group are shown in Table 1. Supplements should be taken with food when taken at doses of 10 mg or more per day.

Table 1: Doses per day for niacin

Life stage group		Niacin (mg/day)
		Minimum¹	Maximum²	Recommended dietary allowance (RDA)³
Children	1 to 3 years 4 to 8 years	0.6 0.6	10 15	6 8
Adolescent males	9 to 13 years 14 to 18 years	0.6 1.0	20 30	12 16
Adult males	19 years and up	1.0	500	16
Adolescent females	9 to 13 years 14 to 18 years	0.6 1.0	20 30	12 14
Adult females	19 years and up	1.0	500	14
Pregnant women	14 to 50 years	1.0	500	18
Breast-feeding women	14 to 50 years	1.0	500	17

Based on approximately 5% of the highest RDA.

Maximum dose for children and adolescents is based on the upper limit which applies to total nicotinic acid and/or niacinamide intake from food and supplements. Specific or dose-specific indication is required for use of niacin products above 35 mg per day.

The RDA provides the minimum dose to help prevent niacin deficiency and provides targets for supplement dosages.

Your health care provider may have recommended using this product in other ways. Contact a health care provider if you have questions.

What is this product used for?

Niacin is generally used for the maintenance of good health.

It is also used to:

• help the body metabolize carbohydrates, fats, and proteins
• help with normal growth and development
• help prevent niacin deficiency (when used at doses at or above the RDA; see Table 1)

Niacin has also traditionally been used for high cholesterol. It is especially effective in increasing the “good” cholesterol HDL and decreasing triglycerides. It is also used to prevent and treat diseases caused by niacin deficiency such as pellagra (symptoms include skin irritation, diarrhea, and dementia).

People have also used niacin for managing Alzheimer’s disease, cataracts, diarrhea due to cholera, diabetes, atherosclerosis, and osteoarthritis. Research suggests that niacin is likely effective for treating high cholesterol and niacin deficiency (including pellagra). However, there is not enough reliable information for its other uses.

Your health care provider may have recommended this product for other conditions. Contact a health care provider if you have questions.

What else should I be aware of?

Niacin is likely safe when taken at recommended doses. Pregnant or breast-feeding women should avoid large doses of niacin because there is a lack of safety information for high doses.

At doses higher than 10 mg per day, niacin can cause temporary skin flushing, which may include burning, tingling, itching, headaches, and redness on the face, arms, and chest. Hot drinks or alcohol can make flushing worse when taken with niacin.

Flushing may be reduced by:

• taking acetylsalicylic acid (ASA) or nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and naproxen before taking each niacin dose
• starting with a small dose of niacin and increasing the dose slowly

Other side effects include gastrointestinal problems such as stomach upset, dizziness, nausea, heartburn, diarrhea, vomiting, and bloating.

Niacin may increase your blood sugar levels. If you have diabetes, check with your health care provider before using niacin. You may need to check your blood sugar more often when using niacin.

Niacin may also increase your risk of bleeding and should be used with caution if you have bleeding disorders or are taking agents that can increase this risk (e.g., anticoagulants, aspirin).

Ask your doctor if you need to have regular liver function tests while you are taking niacin. You should also see your doctor before taking niacin if you have angina, gout, heart disease, fatty deposits in the tendons (tendon xanthomas), gallbladder disease, low blood pressure, or thyroid problems.

There may be an interaction between niacin and any of the following:

• alcohol
• allopurinol
• anticoagulants (e.g., warfarin, heparin)
• aspirin
• antiplatelets (e.g., clopidogrel)
• blood-pressure-lowering medications (e.g., hydrochlorothiazide)
• bile acid sequestrants (e.g., cholestyramine)
• chromium
• diabetes medications (e.g., metformin)
• gemfibrozil
• nicotine
• probenecid
• selenium
• statins (e.g., atorvastatin, fluvastatin)
• sulfinpyrazone
• thyroid hormone (e.g., levothyroxine)
• certain vitamins (e.g., vitamin A, vitamin C, vitamin K)
• zinc

Stop taking niacin at least 2 weeks before surgery.

Do not use niacin if you have:

• active peptic ulcer disease
• active bleeding
• allergy to niacin or niacinamide
• liver disease
• kidney disease

Before taking any new medications, including natural health products, speak to your physician, pharmacist, or other health care provider. Tell your health care provider about any natural health products you may be taking.

Source(s)

1. Health Canada. Licensed Natural Health Products. Multi-Vitamin / Mineral Supplements Monograph. https://webprod.hc-sc.gc.ca/nhpid-bdipsn/atReq.do?atid=multi_vitmin_suppl&lang=eng.
2. Natural Medicines Comprehensive Database. Niacin.