Vitamin B3: functions, food sources and consequences of its deficit

Niacin or vitamin B3 is vital for the functioning of the body. We tell you how you can include it in your diet to make the most of it and not suffer from its deficiency.

Last update: 06 September, 2021

Vitamins are organic substances that the body needs for metabolic processes, such as promoting growth, forming hormones, blood cells, and chemicals. Among them is niacin or vitamin B3.

This vitamin is part of the B complex. The B complex is a group of 8 vitamins with functions related to cellular metabolism. In this article we tell you where you can get it and what happens if it is deficient.

Functions of vitamin B3

Vitamin B3 is important to maintain the body. It can be consumed as nicotinic acid or as niacinamide or nicotinamide. As an acid, it helps regulate cholesterol and heart problems. In contrast, niacinamide does not have that ability.

Together, they help the nervous, digestive and skin systems function. Together with other vitamins, such as riboflavin and pyridoxine, they generate metabolic energy, synthesize sex hormones and growth hormones. They also help take advantage of calcium, carbohydrates, fats, and proteins.

Studies with mice affirm that nicotinamide or vitamin B3 it could be used to fight infections caused by antibiotic resistant staph. In the laboratory, vitamin B3 was shown to increase the immune system's ability to kill bacteria by up to 1,000 times.

Foods rich in vitamin B3

The body can also make vitamin B3 from tryptophan. It is an amino acid released when proteins are digested.

60 milligrams of tryptophan obtained from the diet can replace 1 milligram of niacin. The recommended daily dose is between 12 and 18 milligrams, but it all depends on factors such as gender and age.


Anchovies, tuna and swordfish are the fish that contain the most vitamin B3. In the case of anchovies, they provide about 19 milligrams of niacin per serving of 100 grams of product. It is a little more than recommended per day. On tuna, it provides 18 milligrams and swordfish, 10 milligrams.

Various fish are a source of vitamin B3. Among them, anchovies stand out.


Lamb liver provides, per 100 gram serving, 13.7 milligrams of niacin. The pork provides 11.8 milligrams and the beef about 13.2.


The chicken, specifically its breast, it is also a good source of niacin. For every 100 grams it provides 12.4 milligrams of vitamin B3.


Paprika, which is a common ingredient in cooking, apart from being high in minerals like potassium, phosphorus and magnesium, is also high in niacin. Every 100 grams provides 6.4 milligrams of this vitamin.


Turkey contains 8 milligrams of niacin in its serving. But in addition, it has large amounts of tryptophan, which works for the body to create more vitamin B3 on its own.


Peanuts are a legume that contains 15.9 milligrams of niacin per 100 grams. In addition, it provides minerals, such as 744 milligrams of potassium, 388 of phosphorus and 188 milligrams of magnesium.

Ground beef

Ground beef is common in the diet. Every 100 grams contains 4.82 milligrams of niacin.

Other relevant nutrients that it has are 19.4 grams of protein, 12 grams of fat and 14.2 of selenium. Among the most relevant minerals is potassium, with 289 grams per serving, and phosphorus with 175 grams.

Rice bran

Rice bran is the outer covering of rice grains. It is something that is usually eliminated in the refining process. It contains 34 milligrams of niacin.

In addition, it is a great source of carbohydrates, providing 49.7 milligrams of these, and 21 milligrams of fiber. Protein provides 13.4 milligrams.

As for minerals, it has 57 milligrams of calcium, 18.5 milligrams of iron, 781 of magnesium, 1,680 of phosphorus and 1,480 milligrams of potassium.

Wheat bran

Just as rice has a layer that covers it, so does wheat. That is what is known as wheat bran and is removed during refining.

Nevertheless, that bran is nutritious. It contains 13.6 milligrams of niacin and large amounts of phosphorus, potassium, and magnesium, with 1010, 1180, and 611 milligrams, respectively.

Wheat bran is increasingly used for baking.

Vitamin B3 deficiency

Vitamin B3 deficiency is known as pellagra. Symptoms of this disease include delusions, diarrhea, weakness, loss of appetite, abdominal pain, and skin ulcers in areas exposed to the sun. It also occurs when there is a lack of tryptophan or some other vitamin belonging to the B complex.

The causes are usually anorexia, gastrointestinal malabsorption diseases, alcoholism and the use of some medications. Its treatment involves increasing niacin in the body with supplements. If the problem is not addressed, the person can be left with consequences in the nervous system.

Can you make excess niacin?

The recommended amount of niacin per day is 16 milligrams in men. In non-pregnant adult women the value is 14 milligrams daily. Consuming too much vitamin B3 can cause hot flashes, itchy body, dizziness, fainting, diarrhea, and stomach problems.

Including this vitamin in the diet is important to maintain the proper functioning of the body. Therefore, you can incorporate whole grains that include bran. This way you will enjoy the benefits.