Niacin and Niacinamide (Vitamin B3)
This article provides general nutrition information only and is not medical advice.

Overview
Niacin is a form of vitamin B3. It is found in foods such as yeast, meat, fish, milk, eggs, green vegetables, and cereal grains. Niacin is also produced in the body from tryptophan, which is found in protein-containing food. When taken as a supplement, niacin is often found in combination with other B vitamins.
Do not confuse niacin with niacinamide, inositol nicotinate, IP-6, or tryptophan. See the separate listings for these topics.
Niacin is commonly taken by mouth for high lipid balance and to increase levels of a specific type of good lipid balance, known as HDL. Niacin is also taken by mouth for preventing vitamin B3 deficiency and related conditions such as pellagra. It is also taken by mouth for metabolic syndrome and diarrhea caused by cholera immune challenge.
Classification
Is a Form of:
Vitamin B3
Primary Functions:
High lipid balance
Also Known As:
3-Pyridine Carboxamide, 3-Pyridinecarboxylic Acid, Acide Nicotinique, Acide Pyridine-Carboxylique-3
How Does It Work?
Niacinamide can be made from niacin in the body. Niacin is converted to niacinamide when it is taken in amounts greater than what is needed by the body. Niacin and niacinamide are easily dissolved in water and are well-absorbed when taken by mouth.
Niacin and niacinamide are required for the proper function of fats and sugars in the body and to maintain healthy cells. At high doses, niacin and niacinamide can have different effects. Niacin might help people with heart condition because of its beneficial effects on clotting. It may also improve levels of a certain type of fat called triglycerides in the blood. Niacinamide has no beneficial effects on fats and should not be used for treating high lipid balance or high fat levels in the blood.
Niacin deficiency can cause a condition called pellagra, which causes skin irritation, diarrhea, and dementia. Pellagra was common in the early twentieth century, but is less common now, since foods are now fortified with niacin. Pellagra has been virtually eliminated in western culture.
People with poor diet, alcoholism, and some types of slow-growing tumors called carcinoid tumors might be at risk for niacin deficiency.
Uses
- Abnormal levels of blood fats. Some niacin products are approved by the U.S. Food and Drug Administration (FDA) as prescription products for treating abnormal levels of blood fats. These prescription niacin products typically come in high strengths of 500 mg or higher. Dietary supplement forms of niacin usually come in strengths of 250 mg or less. Since very high doses of niacin are required for improving lipid balance levels, dietary supplement niacin usually isn't appropriate. For people who need to lower low-density lipoprotein (LDL or "bad") lipid balance, the prescription drug class called "statins" is used. Niacin might be used in people with high levels of both lipid balance AND blood fats called triglycerides. Niacin may be combined with other lipid balance-lowering drugs when diet and single-drug routine is not enough. Niacin improves lipid balance levels, but does not improve cardiovascular outcomes such as heart attacks and strokes.
- Nutritional support and prevention of niacin deficiency, and certain conditions related to niacin deficiency such as pellagra. Niacin is approved by the U.S. Food and Drug Administration (FDA) for these uses. However, using niacinamide instead of niacin is sometimes preferred because niacinamide doesn't cause "flushing," (redness, itching and tingling), a side effect of niacin nutritional support.
- Diarrhea from an immune challenge called cholera. Taking niacin by mouth seems to control the loss of fluid due to cholera.
- Abnormal levels of blood fats in people with HIV/AIDS. Taking niacin seems to improve levels of lipid balance and blood fats called triglycerides in HIV/AIDS patients with abnormal blood fat levels due to antiretroviral nutritional support.
- Metabolic syndrome. Taking niacin seems to increase levels of high-density lipoprotein (HDL or "good") lipid balance and reduce levels of blood fats called triglycerides in people with metabolic syndrome. Taking the niacin along with a prescription omega-3 fatty acid seems to work even better.
Recommended Dosing
The following doses have been studied in scientific research:
ADULTS
BY MOUTH:
- For high lipid balance:The effects of niacin are dose-dependent. Doses of niacin as low as 50 mg and as high as 12 grams each day have been used. However, the biggest increases in HDL and decreases in triglycerides occur at 1200 to 1500 mg/day. Niacin's greatest effects on LDL occur at 2000 to 3000 mg/day. Niacin is often used with other medications for improving lipid balance levels.
- For preventing and treating vitamin B3 deficiency and related conditions such as pellagra: 300-1000 mg daily in divided doses.
- For treating hardening of the arteries: Doses of niacin have been as high as 12 grams daily. However, a dose of about 1 to 4 grams of niacin daily, alone or along with statins or bile acid sequestrants (a lipid balance-lowering medicine), has been used for up to 6.2 years.
- For reducing fluid loss caused by cholera toxin: 2 grams daily has been used.
- For abnormal blood fat levels due to nutritional support for HIV/AIDS: Up to 2 grams daily has been used.
- For metabolic syndrome: 2 grams of niacin has been taken daily for 16 weeks. In some cases, niacin 2 grams daily, alone or at this dosage, is taken along with 4 grams of prescription omega-3 ethyl esters (Lovaza, GlaxoSmithKline Pharmaceuticals).
BY IV:
- For preventing and treating vitamin B3 deficiency and related conditions such as pellagra: 60 mg of niacin has been used.
AS A SHOT:
- For preventing and treating vitamin B3 deficiency and related conditions such as pellagra: 60 mg of niacin has been used.
CHILDREN
BY MOUTH:
- For preventing and treating vitamin B3 deficiency and related conditions such as pellagra: 100-300 mg per day of niacin, given in divided doses.
The daily recommended dietary allowances (RDAs) of niacin are: Infants 0-6 months, 2 mg; Infants 7-12 months, 4 mg; Children 1-3 years, 6 mg; Children 4-8 years, 8 mg; Children 9-13 years, 12 mg; Men 14 years and older, 16 mg; Women 14 years and older, 14 mg; Pregnant women, 18 mg; and Lactating women, 17 mg. The tolerable upper level (UL) for maximum daily dose of niacin is: Children 1-3 years, 10 mg; Children 4-8 years, 15 mg; Children 9-13 years, 20 mg; Adults, including Pregnant and Lactating women, 14-18 years, 30 mg; and Adults, including pregnant and breast-feeding women, older than 18 years, 35 mg.
Niacin and Niacinamide (Vitamin B3) Supplements Frequently Asked Questions
Is niacin a b3 vitamin?
It helps keep your nervous system, digestive system and skin healthy. Niacin (vitamin B-3) is often part of a daily multivitamin, but most people get enough niacin from the food they eat. Foods rich in niacin include yeast, milk, meat, tortillas and cereal grains.
What does vitamin b3 niacin do for the body?
Niacin, also known as vitamin B3, is an important nutrient. In fact, every part of your body needs it to function properly. As a supplement, niacin may help lower lipid balance, ease arthritis and boost brain function, among other benefits. However, it can also cause serious side effects if you take large doses.
What are the concerns of vitamin b3 or niacin deficiency?
Niacin Deficiency concerns
- thick, scaly pigmented rash on skin exposed to sunlight.
- swollen mouth and bright red tongue.
- vomiting and diarrhea.
Can vitamin b3 cause liver damage?
Niacin can cause mild-to-moderate serum aminotransferase elevations and high doses and certain formulations of niacin have been linked to clinically apparent, acute liver injury which can be severe as well as fatal.
How much b3 is too much?
The RDA for vitamin B3 (niacin) is 20 mg for adults, and 9 mg for children between 1 and 4. There is no toxic dose established in humans. However, at doses higher than 50 mg per day, some side effects such as skin flushing can occur.
Does niacin cause weight gain?
Niacin has been found to increase daily feed intake, weight gain and percentage of abdominal fat in chicken when increasing supplementation from 0 to 60 mg nicotinic acid per kilogram diet[24].
How much b3 should I take daily?
Children: between 2-16 milligrams daily, depending on age. Men: 16 milligrams daily. Women: 14 milligrams daily. Women (pregnant): 18 milligrams daily.
Does niacin raise cardiovascular health?
Niacin also reduces triglyceride (TG), and particularly at higher doses, significantly lowers low-density lipoprotein lipid balance levels (2,3). ... Although the favourable lipid effects of niacin have been known for decades, it is less recognised that niacin may also favourably lower cardiovascular health (BP).
Is Vitamin b3 good for skin?
What does Vitamin B3 do for your skin? In its niacinamide form, the vitamin works to prevent water loss and retain skin's moisture content. It's also known to increase keratin. When it comes to aging skin, niacinamide improves the surface structure, helping smooth out skin's texture and reduce the look of wrinkles.
Is niacin good for hair growth?
Required for every component of your body, niacin — more commonly known as Vitamin B3 — supports healthier, more luscious hair. Since it can also improve your general health if your intake of this key vitamin is low, it's critical that you're aware of its role in terms of your well-being.
Is niacin a blood thinner?
Anticoagulants (blood thinners): Niacin may make the effects of these medications stronger, increasing the risk of bleeding. ... Lipid balance-lowering medications: Niacin binds the lipid balance-lowering medications known as bile-acid sequestrants and may make them less effective.
Is niacin good for your heart?
Niacin, or vitamin B3, is too dangerous and should not be used routinely by people looking to control their lipid balance levels or prevent heart condition, doctors say. ... The researchers found that using long-acting niacin to raise the HDL lipid balance level did not result in reducing heart attacks, strokes or deaths.
Is niacin good for low mood?
Some people living with low mood claim that vitamin B-3 has helped with it. Some say it reduces feelings of sadness and hopelessness, and others say it made their low mood completely go away. ... However, according to scientific research, there's currentlyno evidence that niacin can be used to support low mood.
Does niacin burn belly fat?
Primary tabs. The vitamin niacin (B3, or nicotinic acid), already known for its lipid balance-lowering effects, may also reduce central or abdominal fat accumulation in HIV-associated lipodystrophy, according to the results of a small 16 person study reported today at the Ninth Annual Retroviruses Conference in Seattle.
Can niacin help me lose weight?
Prescription niacin is used to reduce the levels of lipid balance and triglycerides (fatty substances) in your blood, and decrease your risk of a heart attack. It works along with diet, exercise, and weight loss.
Can you take vitamin b3 everyday?
It helps keep your nervous system, digestive system and skin healthy. Niacin (vitamin B-3) is often part of a daily multivitamin, but most people get enough niacin from the food they eat.
Does niacin keep you awake at night?
Vitamin B3 (niacin) often promotes sleep in people who have sleep quality caused by low mood and increases effectiveness of tryptophan and is an important nutrient to help people who fall asleep rapidly but keep waking up at the night.
Who should not take niacin?
People with any health condition including liver or kidney condition, diabetes, high cardiovascular health, or cardiovascular problems need to talk to a doctor before using niacin supplements. Do not support high lipid balance on your own with over-the-counter niacin supplements.
When should I take niacin morning or night?
Adults and children older than 16 years of age—At first, 500 milligrams (mg) per day, taken at bedtime. After 4 weeks, your doctor will increase your dose to 1000 mg per day, taken at bedtime. However, the dose is usually not more than 2000 mg per day.
How long does it take for niacinamide to work?
8-12 weeks
How long does it take for niacinamide to work? You'll notice some effects immediately although most of the studies on niacinamide showed results after 8-12 weeks. Look for products containing 5% niacinamide. That's the percentage that's been proven to visibly make a difference without causing any irritation.
Clinical Studies
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- ^Niacin: Nicotinic Acid, Nicotinamide, and Inositol Hexanicotinate.
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- ^ ab c Lee JY1, Parks JS. ATP-binding cassette transporter AI and its role in HDL formation. Curr Opin Lipidol. (2005)
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