Vitamin B3: benefits, deficiency, sources

SUMMARY :

What is Vitamin B3?
What are the benefits and indications of vitamin B3?
What are the symptoms of vitamin B3 deficiency?
Where to find vitamin B3 in food?
What are the recommended vitamin B3 intakes?
What are the risks in case of vitamin B3 overdose?

What is Vitamin B3?

Vitamin B3 is also called “vitamin PP” (pellagra preventive), “niacin” and “nicotinic acid”. It is hydrosoluble (soluble in water) and is one of the B vitaminslike vitamins B1, B2, B5, B6, B8, B9 and B12. Its amide is nicotinamide. Redox cofactor, vitamin B3 is a precursor of NAD+ (nicotinamide adenine dinucleotide) and NADP+ (nicotinamide adenine dinucleotide phosphate), coenzymes essential for metabolism. Vitamin PP participates in the transformation of nutrients into energy, in the synthesis of fatty acids and in the production of sex hormones (testosteroneestrogen, progesterone) as well as red blood cells.

What are the benefits and indications of vitamin B3?

Vitamin B3 is a cholesterol-lowering agent: it is known for its ability to reduce the concentration of cholesterol in the blood. In addition, it raises the level of HDL cholesterol (high density lipoproteins), commonly called “good cholesterol”. HDL cholesterol transports cholesterol to the liver to be broken down. Thus, it “cleans” the arteries of bad cholesterol and reduces the risk of atherosclerosis, that is to say the obstruction of the arteries by clusters of lipids and other cells.

Vitamin B3 is essential for proper functioning of the nervous system. It has benefits on brain function (memory, concentration, reasoning). A study by researchers from the École polytechnique fédérale de Lausanne, published in the journal Science in 2016, shows that vitamin B3 regenerates the cells of the skin, muscles and brain in mice. During a study on genetically modified flies, a team from the University of Leicester showed that vitamin B3 protects dopaminergic neurons from degeneration, which would make it possible to fight against Parkinson’s disease.

Vitamin B3 helps maintain normal skin. According to some sources, it would have benefits on the hair by stimulating blood circulation at the root and delaying the aging of hair cells. scalp. In addition, vitamin B3 would promote sleep by reducing stress and stabilizing mood. However, it should be noted that European health authorities do not allow niacin products to claim:

improve hair growth via microcirculation in the scalp;
improve nail growth;
be essential for healthy hair, nails, teeth, bones and skin;
maintain normal cholesterol and triglyceride levels;
help maintain normal blood circulation.

What are the symptoms of vitamin B3 deficiency?

Vitamin B3 deficiency causes pellagra. This disease is manifested by chronic diarrhea, hyperpigmentation of the skin in areas exposed to the sun, dermatological lesions and neurological disorders (dementia). Taking vitamin B3 supplements can treat pellagra, which is the origin of the name “vitamin PP”: Pellagra Preventive.

Lack of vitamin B3 can affect people with chronic bowel diseases (Crohn’s disease and celiac disease) as well as people with alcoholism and cirrhosis.

Where to find vitamin B3 in food?

Foods rich in vitamin B3 include Royal jellybaker’s yeast, rice bran, whole grains, liver, meat and fish.

What are the recommended vitamin B3 intakes?

ANSES (National Agency for Food, Environmental and Occupational Health and Safety) defines vitamin B3 requirements in milligram EN/MJ (niacin equivalent per megajoule. The average nutritional requirements (ANR) are 1.3 mg NE/MJ and the Dietary Reference for the Population (RNP) is 1.6 mg NE/MJ.

According to ANSES, the upper safety limit (LSS) is:

2 mg EN/MJ for children 1 to 3 years old;
3 mg EN/MJ for children 4 to 6 years old;
4 mg EN/MJ for children 7-10 years old;
6 mg EN/MJ for adolescents 11-14 years old;
8 mg EN/MJ for adolescents 15-17 years old;
10 mg EN/MJ for men and women 18 years and older.

Other sources specify the recommended intakes of vitamin B3 in milligrams per day: 14 mg/d for men and 11 mg/d for women.

Vitamin B3 can be provided in the form of dietary supplement in capsules or tablets, available in pharmacies and on online sales sites. Vitamin supplements contain nicotinamide, which is easier to absorb. In case of deficiency, the dosage can reach 500 to 1000 mg per day. Nicotinamide tablets are available by prescription.

What are the risks in case of vitamin B3 overdose?

The therapeutic use of vitamin B3 must imperatively be done under medical advice. Indeed, an overdose of nicotinic acid can lead to side effects : hot flushes accompanied by redness in the face, chest and neck, headaches, stomach aches, nausea, diarrhea, vomiting or itching. A Vitamin B3 overdose is also harmful for the liver and can lead to symptoms of diabetes.

On the other hand, nicotinic acid can interact with certain medications, including blood thinners, and treatments for cholesterol, high blood pressure, epilepsy, type 2 diabetes, and heart problems. It is therefore important to inform your doctor of taking vitamin B3 before starting treatment or taking another food supplement.

Taking high doses of vitamin B3 is not recommended for pregnant women and breastfeeding women. It is also contraindicated for people suffering from diabetes, liver problems, kidney stones or excess uric acid.

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