Facts About Vitamin B3 (Niacin)

Vitamin B3 Niacin

There are eight essential water-soluble vitamins, including vitamin B3. Besides aiding in the proper function of the nervous system and digestive system, it also lowers cholesterol and maintains skin and hair health. B3 is also crucial to the process of breaking down food for energy synthesis. Over 200 enzymes rely on it to function. Aside from signaling cells, it synthesizes and repairs DNA.

The name B3 is appropriate since this vitamin exists in 3 forms, which are nicotinamide, niacin, nicotinamide, and nicotinamide riboside. NAD also know as Nicotinamide Adenine Dinucleotide, is synthesized within the body from these 3 forms of vitamin B3. NAD cannot be synthesized without at least one of the B3 vitamins. A crucial amino acid called tryptophan is also required by the body in order to complete the synthesis of NAD.


Among the essential nutrients for healthy bodily functions, vitamin B3 plays a significant role. Vitamin B3 is essential for heart health and for metabolism regulation. Because it can lower cholesterol and triglyceride levels, it plays a very key role in possibly reducing cardiovascular disease. Several studies have shown that consumption of foods containing vitamin B3 (Niacin) can lead to lower levels of LDL, which is the cholesterol that is often referred to as bad cholesterol, and increased levels of HDL, which is the cholesterol that is often referred to as good cholesterol. Additionally, it can also benefit brain function as well as skin health, and even prevent or treat diabetes.


In order for the body to function properly and to achieve its maximum health and performance potential, Niacin is essential. There are a variety of benefits to taking Niacin.

In the following list, we have outlined the major health benefits that can be derived from taking Niacin supplements, or making sure adequate amounts are obtained from your diet.

Improve Cholesterol

Among its benefits is lowering cholesterol levels, which is why niacin is considered effective in the treatment of heart disease. People with mixed dyslipidemia, characterized by an increase of cholesterol and triglycerides or both, Vitamin B3 has been shown to decrease the risk of heart disease.

Niacin supplementation has been demonstrated to be helpful for people with elevated levels of LDL cholesterol, decreased levels of HDL cholesterol, or increased triglyceride levels due to an increased risk for heart attacks, strokes, or other forms of heart disease.

There has been research showing that high doses of niacin boost levels of the healthy HDL cholesterol and reduce triglycerides as well as certain prescription medications can.
Furthermore, it lowers LDL cholesterol. For cholesterol control, it is commonly prescribed along with statin medications such as Crestor, Lescol or Lipitor. 

Help Blood Sugar & Diabetes

Blood sugar levels are balanced and the symptoms of diabetes are controlled with niacin due to its ability to balance blood sugar levels. The molecule Niacinamide, is a form of vitamin B3, may improve the functioning of beta cells, which are an instrumental part of the blood sugar control system. Beta cells produce insulin, which plays an instrumental role in regulating blood sugar.

Niacin may lower both the risk of high blood cholesterol and heart disease for diabetic patients as well as help them control blood sugar levels better. People with diabetes commonly suffer from both conditions.

Several studies have suggested that niacin may also be involved in complications that arise from high blood sugar. Because there are some conflicting data regarding niacin and high blood sugar, it is best to consult a physician before taking any form of niacin to avoid adverse reactions.

Reduce Heart Disease Risk

It is well known that vitamin B3 can help reduce the effects of atherosclerosis. This is the condition in which arteries harden and that can result in coronary heart disease if not treated.

The ability of Niacin to cause the reduction of LDL in the blood can reduce the risk of recurrence of heart disease, including cardiac arrest, in those who have already suffered from heart disease or cardiac arrest.

Improves Skin

It is widely known that niacin, or niacinamide, is used effectively for skin health as well as inflammatory and acne conditions. Vitamin B3 is known for its ability to help clear acne when administered as a topically applied treatment in the form of niacinamide. Niacin or a vitamin complex containing B vitamins can be used to reduce acne symptoms in some people.

Due to niacin’s ability to aid in reducing redness, inflammation, irritation, as well as other skin conditions, it is also used to treat conditions such as bullous pemphigoid and granuloma annulare.

Brain Health

The benefits of vitamin B3 have been studied and it has been shown that vitamin B3 may protect the brain against conditions such as Alzheimer’s disease, dementia and age-based cognitive decline. Additionally, it can also be used as a treatment and prevention method for schizophrenia and hallucinations. In addition to this, numerous studies have demonstrated the efficacy of niacin as a therapeutic intervention for mental illnesses such as bipolar disorder, depression, anxiety disorders, and others.

Treatment of Pellagra

Pellagra, is a condition associated with poverty, eating disorders, and alcoholism, is caused by a vitamin B3 deficiency. A person suffering from Pellagra might experience muscle weakness, digestive issues, inflammation, or skin irritation.

People who suffer from pellagra have low amounts of niacin and other B vitamins in their system. Normally, this occurs due to either a deficiency of niacin in the diet or other contributing factors, like problems with protein metabolism or difficulty absorbing amino acids. As a result of a lack of vitamin B3, patients with pellagra can die in a few years if their levels are not restored to normal.

The typical way to treat pellagra is by prescribing large amounts of vitamin B3, in the form of nicotinamide, which is a type of vitamin B3. Nicotinamide is similar to niacin in function, but differs in absorption and side effects.

Digestive Health

Niacin plays an instrumental role in promoting healthy function of the digestive tract, a healthy appetite, and healthy nerve function, as well as an improved skin complexion.

Energy production

A very important function of vitamin B3 is its ability to convert carbohydrates, proteins and fats into energy.

Joint Health

The molecule Niacinamide, is a form of vitamin B3, that has been demonstrated to increase joint mobility in some research. Studies have shown an association between an increased intake of niacin and reduced joint pain plus a decreased level of inflammation that tends to accompany conditions such as osteoarthritis. Niacinamide taken at high doses has been shown to reduce swelling and improve flexibility in studies.

By taking niacinamide, many people can lessen their dependency on painkillers and arthritis medicines. Niacin is prescribed in high doses to treat osteoarthritis and bone and joint pain due to its anti-inflammatory properties. By reducing inflammation, arthritis symptoms may be diminished and joint cartilage can be rebuilt to improve joint mobility and strength.

Impotence or erectile Dysfunction

Niacin is a vasodilator that helps to increase blood flow throughout the body helping to prevent erectile dysfunction by acting as a vasodilator and helping to increase blood flow.

It has been discovered that the nutrient niacin improves the quality of life for men who suffer from mild to severe erectile dysfunction, and dyslipidemia. This was discovered in a 2011 study by researchers at the Chinese University of Hong Kong. A study shows that 1,500 milligrams of niacin per day is an effective treatment for impotence in men suffering from the problem.

0 to 6 months2 mg2 mg
7 to 12 months4 mg4 mg
1 to 3 years6 mg6 mg
4 to 8 years8 mg8 mg
9 to 13 years12 mg12 mg
14 to 18 years16 mg14 mg
19+ years16 mg14 mg
The Recommended Dietary Allowances or RDA for Vitamin B3 from the NIH


In developed countries with low malnutrition rates, niacin deficiency is uncommon. Alcohol abuse, malnutrition, and digestive disorders, as well as medications that interfere with absorption, are some of the most common causes of deficiency.

When you don’t consume enough niacin or tryptophan as part of your diet you can develop a niacin deficiency. There is a condition known as pellagra that occurs when there is a severe niacin deficiency. In developed countries, pellagra is considered an uncommon health condition. Pellagra leads to loss of appetite and death in its final stages.


The main cause of a Vitamin B3 deficiency is the same as the cause of a Vitamin B2 deficiency, which is an insufficient nutritional intake. Niacin deficiency can be brought on by a variety of factors, such as things that may increase the excretion of this vitamin from the body. In some cases, a deficiency may also result from the body’s inability to absorb the vitamin.

The following is a list of some of the factors that may contribute to having a deficiency:

  • Alcoholism
  • Digestive disorders
  • Malnutrition
  • Medications that interfere with absorption of the vitamin
  • Medications that increase excretion of the vitamin
  • deficiency of the amino acid Tryptophan



In developed countries, alcoholism is one of the most common causes of Niacin deficiency. The reason for this is because often alcoholics will forgo nutritional intake in favor of alcohol intake. This invariably leads to malnutrition and a deficiency.

Eating Disorders

In developed countries, eating disorders such as anorexia cause a high rate of Niacin deficiency because of the link they have to malnutrition. An anorexic consumes super low amounts of food and calories in a day and as a result becomes malnourished very quickly resulting in deficiencies in many nutrients including Niacin, along with the amino acid L-Tryptophan which is essential for Vitamin B3.

Inflammatory bowel disease

People with inflammatory bowel disease (IBD) such as ulcerative colitis or Crohn disease can be at risk for a B3 deficiency because they may have difficulty absorbing key nutrients and amino acids.

Carcinoid Syndrome

Carcinoid syndrome is a condition characterized by the growth of slow-growing tumors in the GI tract. During the growth of these tumors, serotonin and other chemicals are released into the body. The symptoms of this disorder are facial flushing, diarrhea, and other symptoms. It has been determined that people with carcinoid syndrome are more likely to oxidize tryptophan into serotonin than niacin. Therefore, a lesser amount of tryptophan is available for conversion into niacin, leading to a deficiency.

Hartnup Disease

Hartnup disease is a rare genetic disorder affecting the transport of amino acids, including tryptophan, through the kidneys, the digestive tract, and the cellular membrane. As a result of the disease, tryptophan is not absorbed from the small intestine and is instead lost to urine through the kidneys. This results in less tryptophan available for conversion to niacin in the body.


Niacin deficiency is characterized by 4 key clinical symptoms, which are usually called the 4 D’s of Niacin deficiency. Dermatitis, diarrhea, dementia, and death. Digestion problems, such as constipation, diarrhea, nausea, and vomiting, are the most common signs and symptoms of Niacin deficiency. Other signs can include swelling of the tongue and mouth, dermatitis (skin irritation), thickening of the skin, and changes in skin color. Severe B3 deficiencies can cause in some cases amnesia, delirium, depression, and psychoses.

The most common result of a Niacin deficiency is the condition known as Pellagra.


The symptoms of pellagra include a brown rash or discoloration of the skin exposed to sunlight. A rough and irritated appearance also manifests on the skin. Furthermore, pellagra can cause your tongue to turn a bright red color and can also cause abnormalities in your digestive tract, which may result in vomiting, constipation, or diarrhea.

There are several neurological symptoms that are associated with pellagra, including fatigue, depression, apathy, headaches, and memory loss that may develop into aggression, paranoia, and suicidal behavior; as well as visual and auditory hallucinations. Eventually, the individual suffering from pellagra will develop anorexia and die.


Toxicity affects the body in several ways including nausea, vomiting, diarrhea, flushing, palpitations, and dizziness. In order to treat toxicity, supportive measures such as gastric lavage should be taken. Naturally occurring niacin exists in foods in a form that has not been associated with any adverse effects. However, too much vitamin B3 (niacin) supplementation can have adverse effects. Niacin is water-soluble, just like the other B vitamins.

Therefore, excess amounts of niacin are excreted through the urine in order to prevent niacin toxicity and overdose. This is why consuming a lot of foods high in vitamin B3 is not likely to cause adverse side effects. Because of this it is considered a safe way to ensure you get the recommended daily allowance. The risk of side effects and toxicity is only present when people take an excessive amount of B3 in supplement form.

Even though the risk of toxicity is very low, there are still side effects or adverse reactions that can occur with Niacin, especially with Niacin supplements. Below are some of the side effects that can be caused by too much Niacin.

Niacin Flush

Through prostaglandin D2, niacin vasodilates the small vessels in the subcutaneous tissues. The dilating of the small blood vessels results in a flushing of the skin, accompanied by the unpleasant sensation of pruritus and warmth. If the flushing is severe, hypotension and dizziness may result.


In diabetics, glucose tolerance may be reduced and hyperglycemia may result. After moderately sized doses of Niacin, insulin resistance is thought to occur due to free fatty acid rebound.

Peptic Ulcer Disease

Peptic ulcer disease may be aggravated by niacin supplementation. Therefore, it is important to use niacin cautiously if one has gastrointestinal disorders that are active or chronic.


Hepatotoxicity is by and large the most serious side effect of niacin. It is common for transaminase levels to rise up to double the normal range.


Niacin causes a condition known as hyperuricemia, which occurs when the body accumulates too much Uric Acid. Hence, niacin should not be taken by people who have gout or those who have a history of gout.


There is a wide range of food sources that contain vitamin B3. In addition to being included in processed foods and fortified foods, B3 can also be found in energy drinks. Most people living in North America will not have to worry about getting enough Vitamin B3 as their normal diet will provide them with adequate amounts of this nutrient. Furthermore, they will easily meet their recommended daily allowance.


  • Rice
  • Peanuts
  • Bread
  • Potatoes
  • Breakfast Cereals
  • Sunflower Seeds
  • Pumpkin Seeds
  • Soymilk
  • Lentils
  • Banana
  • Raisins
  • Tomatoes
  • Broccoli
  • Cashews
  • Apples


  • Beef
  • Chicken
  • Fish
  • Pork
  • Yogurt
  • Milk
  • Eggs