Vitamin B3: A Key Nutrient for Your Health

What is Vitamin B3 and Why is it Important?

Vitamin B3 (incl. niacin) is one of the essential nutrients that plays a fundamental role in the proper functioning of the human body. It belongs to the group of B vitamins, which are water-soluble , which means that the body does not store them in significant amounts and it is necessary to supplement them daily through diet. In addition to the name niacin, vitamin B3 also occurs under two main chemical forms: nicotinic acid and nicotinamide . These different forms, although closely related, may have slightly different effects in the body.

One of the key functions of vitamin B3 is its participation in the process of converting consumed food into energy , which is necessary for all life processes. Niacin is also extremely important for the proper development and functioning of our body cells, influencing many metabolic pathways. To take into account the fact that the human body can also produce niacin from tryptophan , an amino acid present in proteins, a unit called niacin equivalent (NE) was introduced. One milligram of NE corresponds to one milligram of niacin or 60 milligrams of tryptophan, which allows for a precise determination of the need for this vitamin, taking into account both its dietary intake and endogenous synthesis.

The fact that the body can synthesize niacin from tryptophan underscores the importance of consuming sufficient dietary protein to maintain adequate vitamin B3 levels. Tryptophan deficiency, even with some niacin intake, can lead to suboptimal vitamin B3 status . Furthermore, the existence of two major forms of vitamin B3, nicotinic acid and nicotinamide, which have different biological effects, suggests that the type of vitamin B3 consumed may be important in achieving specific health benefits.

How does vitamin B3 work in your body?

Vitamin B3 as a coenzyme

Vitamin B3 acts as a coenzyme in the body, participating in over 400 enzymatic reactions . This broad involvement underscores its fundamental importance in maintaining healthy cellular function and overall health. The key coenzymes that niacin is a part of are nicotinamide adenine dinucleotide (NAD+) and nicotinamide adenine dinucleotide phosphate (NADP+) and their reduced forms (NADH and NADPH) . These molecules are essential for many basic metabolic processes in the body.

Energy production from carbohydrates, fats and proteins

Niacin plays a key role in the production of energy from dietary nutrients such as carbohydrates, fats and proteins. It is also involved in the processes of creating and repairing DNA , which is crucial for maintaining the genetic integrity of cells. In addition, vitamin B3 is involved in the synthesis of cholesterol and fatty acids, which are essential for the construction of cell membranes and the production of hormones. Its role in cell signaling, the process of communication between cells, which is necessary for coordinating various body functions, cannot be overlooked. Additionally, niacin has an antioxidant effect , helping to protect cells from damage caused by free radicals. It is also worth mentioning its importance for the nervous system, where it participates in neuroprotective processes.

The versatile role of niacin in the body

The vast number of enzymes (over 400) that are dependent on niacin underscore its central role in maintaining cellular function and overall health. This broad involvement suggests that niacin deficiency may have far-reaching consequences for various body systems. Furthermore, niacin's involvement in both energy production and DNA repair suggests a potential link between energy metabolism and genetic stability. Adequate niacin intake may therefore be crucial for maintaining the integrity of our genetic material , particularly in tissues with high energy requirements.

Vitamin B3 Supplementation and Health Benefits

The beneficial effect of vitamin B3 on blood cholesterol levels

Vitamin B3 is known for its many health benefits, and adequate intake is essential for maintaining well-being. One well-documented benefit is its effect on managing blood cholesterol levels . Nicotinic acid, a prescription form of niacin, can effectively lower “bad” LDL cholesterol, raise “good” HDL cholesterol, and reduce triglycerides. However, these effects are usually seen at doses much higher than the recommended daily allowance (RDA). Niacin’s mechanisms of action in this regard include inhibiting the release of lipids from fat cells and influencing the production of lipoproteins in the liver. There is ongoing research and some debate about the effect of niacin on cardiovascular events, especially when taken in combination with statins.

Niacin and the cognitive functions of the body

Niacin also has potential benefits for cognitive function . Studies suggest it is linked to better memory and brain health in older adults. There is also some evidence that it may protect against Alzheimer's disease and cognitive decline , although research in this area is still ongoing. In addition, niacin may play a role in treating some types of schizophrenia.
Another important aspect is the beneficial effects of niacin on skin health . It helps maintain healthy skin and may protect skin cells from sun damage, as well as potentially reducing the risk of some types of skin cancer (especially in the form of nicotinamide). Nicotinamide is also a popular ingredient in skin care products for its soothing, moisturizing, and brightening properties.

Where to Find Vitamin B3? Natural Sources in Your Diet

Vitamin B3 in animal products

To ensure adequate vitamin B3 intake, it is worth including a variety of foods rich in this nutrient in your diet. Good animal sources include:

• Poultry (chicken breast, turkey) - it is worth noting that chicken breast contains more niacin than thighs.
• Beef , especially lean meat, is also a good source, as is lean pork.
• Fish , such as tuna, salmon and anchovies, are another valuable source of niacin.
• Organ meats - such as liver and kidney, with liver being one of the richest natural sources of niacin. Eggs and dairy products, such as milk, also provide some of the vitamin.

Sources of vitamin B3 in plant foods

Plant foods rich in niacin include:

• Nuts - e.g. peanuts, sunflower seeds.
• Legumes - e.g. peas, lentils, soybeans.
• Grain products - whole grains, wheat flour, wheat germ, oats, brown rice, although it is worth remembering that the niacin in brown rice may be less bioavailable.
• Fruits , such as bananas and oranges, also contain niacin.
• Vegetables – beets, mushrooms, avocado, broccoli, Brussels sprouts, green leafy vegetables.
• Nutritional yeast - is an exceptionally rich source of this vitamin.
• Fortified foods - such as bread, breakfast cereals and milk, which are often fortified with niacin.

The wide range of both animal and plant sources of niacin suggests that people with different dietary patterns can meet their vitamin B3 requirements through informed dietary choices. However, it is important to be aware of potential differences in bioavailability , for example with brown rice. The fortification of popular foods such as bread and cereals with niacin has probably played a significant role in reducing the incidence of niacin deficiency in developed countries.

That can be helpful: Vitamins and minerals for daily supplementation

What are the symptoms of vitamin B3 deficiency?

Pellagra Symptoms 3D

Severe vitamin B3 deficiency leads to the development of pellagra , a disease that, although rare in developed countries due to food fortification, can still occur. The classic symptoms of pellagra are the so-called "3Ds":

1. Dermatitis (inflammation of the skin) - involves rough skin that turns red or brown in the sun (photosensitivity). A rash appears on areas of the body exposed to the sun, such as the face (butterfly-shaped), neck (Casal's necklace), hands (glove-like), and feet and calves (shoe-like). A bright red tongue is also characteristic.
2. Diarrhea (diarrhea) - may include vomiting, constipation, or diarrhea, which in some cases may be bloody. Sore mouth (stomatitis, glossitis) is also common.
3. Dementia - includes depression, headaches, and extreme fatigue. Aggressive, paranoid, or suicidal behavior may also occur, as well as hallucinations, apathy, memory loss, confusion, and delirium.  
   Less specific early symptoms of niacin deficiency include loss of appetite, restlessness, irritability and feeling constantly tired.
4. Some sources also list death as the fourth "D" if the disease is left untreated.

Risk factors for niacin deficiency

There are many risk factors for niacin deficiency, including:

• Alcohol abuse
• Malnutrition and poverty
• Problems with absorption of nutrients - inflammatory bowel disease, liver cirrhosis, anorexia
• A diet low in iron, riboflavin or vitamin B6 - necessary for the conversion of tryptophan to niacin
• Genetic diseases - such as Hartnup disease and carcinoid syndrome.
• Certain medications , such as isoniazid, can also contribute to niacin deficiency.

The symptoms of pellagra, such as dermatitis, diarrhea, and dementia, represent the systemic effect of severe niacin deficiency in tissues with high energy requirements and rapid cell turnover . The historical prevalence of pellagra in populations relying primarily on corn underscores the importance of dietary diversity and appropriate food processing techniques to ensure the availability of essential nutrients. The overlap of early symptoms of niacin deficiency with those of other medical conditions and less severe vitamin deficiencies suggests that mild niacin deficiency may be underdiagnosed.

See also: Vitamin B1

What happens if we overdose on vitamin B3?

Although naturally occurring niacin in foods is generally safe, consuming high doses of it from dietary supplements can lead to side effects. One of the most common symptoms is the so-called niacin "flush," which is a sudden redness, warmth, itching, and tingling of the face, arms, and chest. While it can be uncomfortable, it is usually harmless and goes away on its own within a few hours. There are strategies that can help reduce the severity of this effect, such as taking aspirin half an hour before taking a niacin supplement and avoiding alcohol and hot beverages.

However, taking very high doses of niacin can lead to more serious side effects. Liver problems, such as elevated liver enzymes, hepatitis , and even liver failure , can occur. It is thought that extended-release forms of niacin may be associated with a higher risk of hepatotoxicity. Other potential side effects include gastrointestinal problems, such as nausea, vomiting, diarrhea, and indigestion , increased blood sugar (especially with nicotinic acid), which is important for people with diabetes, low blood pressure and dizziness, visual disturbances, and gout, caused by increased uric acid levels in the blood. Recent studies also suggest that taking high doses of niacin long-term may potentially increase the risk of cardiovascular events , but these findings require further study. There are also specific upper limits for niacin intake from dietary supplements for different age groups.

Nicotinamide generally causes fewer side effects than nicotinic acid at similar doses, suggesting that it may be the preferred form of supplementation in cases of deficiency when cholesterol management is not necessary. However, nicotinamide does not have the same cholesterol-lowering effects as nicotinic acid.

A recent study linking the metabolite niacin excess (4PY) to increased cardiovascular risk raises concerns about the long-term safety of high-dose niacin supplementation, even for cholesterol management. Interactions of niacin supplements with various medications underscore the importance of consulting a doctor before starting supplementation , especially in people with existing conditions or taking other medications.

How Much Vitamin B3 Do You Need Every Day? Recommended Doses

The recommended daily allowance (RDA) for niacin varies by age, gender, and life stage. The table below shows the recommended doses based on data from the National Institutes of Health (NIH):

AI - Adequate Intake

The Tolerable Upper Intake Level (UL) for adults is 35 mg/day from dietary supplements. It is important to remember that this is for supplements and that niacin intake from food alone is generally safe. Individual needs may vary and the best way to ensure adequate niacin intake is to eat a balanced diet.

The recommended daily intake of niacin varies considerably by life stage, reflecting the body's changing metabolic needs. The establishment of an upper limit for niacin intake from supplements, but not from food, suggests that the risk of adverse effects is primarily related to the concentrated doses found in supplements.

Summary: Vitamin B3 for health and well-being

Vitamin B3, or niacin, is an incredibly important nutrient that plays a key role in many metabolic processes in the body. Adequate intake contributes to maintaining healthy energy levels, a healthy nervous system, skin, and gastrointestinal tract. Niacin also shows promising benefits in managing cholesterol levels, improving cognitive function, and supporting skin health.

To ensure you get enough vitamin B3, you should eat a balanced diet rich in a variety of sources of this ingredient, both animal and plant origin. If you are considering high-dose niacin supplementation, especially for the treatment of hypercholesterolemia, you should consult a doctor who will assess your individual needs and potential risks. Remember that vitamin B3 is essential for our health and well-being, and consciously taking care of its adequate supply is an investment in a long and healthy life.