Niacin (Vitamin B3)

Niacin, also known as vitamin B3 and nicotinic acid, is an organic compound with the formula C6H5NO2 and, depending on the definition used, one of the 20 to 80 essential human nutrients. Pharmaceutical and supplemental niacin are primarily used to treat hypercholesterolemia (high cholesterol) and pellagra (niacin deficiency). Insufficient niacin in the diet can cause nausea, skin and mouth lesions, anemia, headaches, and tiredness. The lack of niacin may also be observed in pandemic deficiency disease, which is caused by a lack of five crucial vitamins (niacin, vitamin C, thiamin, vitamin D, and vitamin A) and is usually found in areas of widespread poverty and malnutrition. Niacin has not been found to be useful in decreasing the risk of cardiovascular disease in those already on a statin but appears to be effective in those not taking a statin.

This colorless, water-soluble solid is a derivative of pyridine, with a carboxyl group (COOH) at the 3-position. Other forms of vitamin B3 include the corresponding amide and nicotinamide (“niacinamide”), where the carboxyl group has been replaced by a carboxamide group (CONH2), as well as more complex amides and a variety of esters. Nicotinic acid and niacinamide are convertible to each other with steady world demand rising from 8,500 tonnes per year in the 1980s to 40,000 in recent years.

Niacin cannot be directly converted to nicotinamide, but both compounds are precursors of the coenzymes nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP) in vivo. NAD converts to NADP by phosphorylation in the presence of the enzyme NAD+ kinase. NADP and NAD are coenzymes for many dehydrogenases, participating in many hydrogen transfer processes. NAD is important in catabolism of fat, carbohydrate, protein, and alcohol, as well as cell signaling and DNA repair, and NADP mostly in anabolism reactions such as fatty acid and cholesterol synthesis. High energy requirements (brain) or high turnover rate (gut, skin) organs are usually the most susceptible to their deficiency.

Niacin has a wide range of uses in the body, helping functions in the digestive system, skin and nervous system. Niacin, a name coined from nicotinic acid vitamin, comes in several forms, including niacinamide (nicotinamide) and inositol hexanicotinate. Each of these forms has various uses as well.

Food sources of niacin include yeast, meat, fish, milk, eggs, nuts, green vegetables, beans and enriched breads and cereals. The human body can also make niacin from the amino acid tryptophan.
Having enough niacin, or vitamin B3, in the body is important for general good health. As a treatment, higher amounts of niacin can improve cholesterol levels and lower cardiovascular risks.

However, niacin is only effective as a cholesterol treatment at fairly high doses. These doses could pose risks, such as liver damage, gastrointestinal problems, or glucose intolerance. So don’t treat yourself with over-the-counter niacin supplements. Instead, get advice from your health care provider, who can prescribe FDA-approved doses of niacin instead.

Niacin has other benefits. There’s good evidence that it helps reduce atherosclerosis, or hardening of the arteries in some people. For people who have already had a heart attack, niacin seems to lower the risk of a second one. In addition, niacin is an FDA-approved treatment for pellagra, a rare condition that develops from niacin deficiency.

Niacin has also been studied as a treatment for many other health problems. There’s some evidence that it might help lower the risk of Alzheimer’s disease, cataracts, osteoarthritis, and type 1 diabetes. However, more research needs to be done.

Vitamin B3, is a water-soluble B vitamin that plays a role in more than fifty different metabolic processes which help the body utilize sugars, proteins, and fatty acids to create energy. It works in conjunction with the other B vitamins to convert macronutrients into energy.

It aids in the functioning of enzymes in the body. Vitamin B3 is required for the activation of many enzymes. Enzymes are compounds that accelerate certain chemical processes in the body.

Niacin is needed for proper functioning of the digestive system – it plays a role in the production of hydrochloric acid, which is needed for good digestive function. It also acts to guard pancreas health.

Vitamin B3 promotes healthy skin and has been utilized as an acne treatment.

It is necessary for regulating the expression of genes and in maintaining genomic activities..
Niacin acts to aid the body in the elimination of of toxins and harmful chemicals.

It facilitates the production of various sex and adrenal hormones.

Vitamin B3 is helps to improve circulatory function as well as reduce blood serum cholesterol levels by inhibiting its accumulation in the arteries and in the liver. Niacin helps to increase the amount of good cholesterol (HDL) and lower the amount of bad cholesterol (LDL) in the blood. Additionaly, it may increase the effectiveness of certain medicines which are prescribed to reduce cholestorol.

Niacin, works in conjunction with chromium to help regulate and stabilize blood sugar levels by promoting proper insulin function.

The two types of vitamin B3 also have particular medical uses: Nicotinic acid is prescribed as an anti-hyperlipidemic agent, while nicotinamide is thought to act as an anti-diabetogenic.


As a member of B-complex vitamins, niacin aids in the normal functioning of the human digestive system, promoting a healthy appetite, properly functioning nerves, and a glowing skin.


People with weak muscles, digestive problems, skin irritation or pellagra may have a severe vitamin B3 deficiency. These people need to administer an increased dosage of vitamin B3 supplements into their diet.


Intake of large quantities of niacin, which would be 1100 or more milligrams in a day, has been proven to considerably reduce the levels of “bad” LDL cholesterol and raise the good HDL cholesterol, which prevents the thickening of artery walls and conditions like atherosclerosis.

Energy Production

Like the other B complex vitamins, niacin is important in energy production. Two unique forms of vitamin B3 (called nicotinamide adenine dinucleotide, or NAD, and nicotinamide adenine dinucleotide phosphate, or NADP) are essential for conversion of dietary proteins, fats, and carbohydrates into usable energy. Niacin is also used to synthesize starch that can be stored in muscles and liver for eventual use as an energy source.

Antioxidant Protection

The same niacin-containing enzymes that are involved in energy metabolism, NAD and NADP, work by quenching free radicals. This process is not only important in energy production, but in protecting your body against excessive tissue damage. While most lay person nutrition sources omit niacin from the list of dietary antioxidants, researchers are aware of this connection, and have studied it extensively, particularly in people with diabetes.

Dietary Deficiency

In industrialized countries, world, most instances of vitamin B3 deficiency appear to be related to medical conditions. By far the most likely reason to see niacin deficiency is alcoholism, a condition that can compromise not only B3 status, but the status of many other nutrients as well.

Many circumstances have combined to dramatically reduce the risk of B3 deficiency in the average U.S. diet. These circumstances include widespread consumption of animal foods—including chicken and turkey—as well as addition of B3 to grain products (like wheat flour or corn meal). The average U.S. adult (age 20 and over) consumes about 26 milligrams of B3 per day, or about 160% of our WHFoods recommended intake amount of 16 milligrams.

Even though animal foods and fish are our richest sources of B3 (with single servings often providing 25% or more of the needed daily amount), it is not difficult for a vegetarian diet to provide ample amounts of B3. Mushrooms, legumes, seeds, and fresh vegetables are often rich in B3. As an example, one serving of crimini mushrooms, one serving of peanuts, one serving sunflower seeds, one serving of sweet potato, and one serving of brown rice add up to about 825 calories and 100% of your daily B3 requirement.