Vitamin B3 (Niacin)

Vitamin B3, also known as niacin, is a water-soluble nutrient that plays a vital role in over 400 biochemical reactions in the body, including converting food into energy, repairing DNA, and producing essential hormones such as sex hormones (estrogen, testosterone), stress hormones (cortisol), and thyroid hormones. It comes in two forms: nicotinic acid and niacinamide, each offering unique health benefits. Nicotinic acid is well-known for helping lower cholesterol and supporting heart health, while niacinamide is widely used for improving skin health, reducing inflammation, and supporting brain function. According to the study “Niacin: The Real Story,” supported by the National Institutes of Health, niacin plays a proven role in cardiovascular health, energy metabolism, and skin protection.

What is Vitamin B3 (Niacin)?

Vitamin B3 is part of the vitamin B-complex family. It is water-soluble, which means the body does not store it in large amounts, so regular intake from food or supplements is important. The body can make small amounts of niacin from the amino acid tryptophan (an essential amino acid used to make proteins, serotonin, and melatonin), found in protein-rich foods. However, most niacin needs come from the diet.

Health Benefits of Vitamin B3

The health benefits of vitamin B3 include improved energy production, better heart and brain health, glowing skin, and reduced inflammation, making it an essential nutrient for overall wellness. 

Supports Energy Production

Niacin helps produce nicotinamide adenine dinucleotide (NAD) and nicotinamide adenine dinucleotide phosphate (NADP), two coenzymes essential for converting carbohydrates, fats, and proteins into energy. Without niacin, your body’s energy production slows down.

Promotes Heart Health

Nicotinic acid can lower low-density lipoprotein (LDL), bad cholesterol, and triglycerides (a type of fat lipid found in your blood that stores energy). while raising high-density lipoprotein (HDL), good cholesterol, reducing the risk of heart disease. It’s sometimes prescribed in high doses for cholesterol management.

Boosts Brain Function

Niacin supports brain health by aiding nerve signaling and protecting brain cells. Deficiency can cause confusion, memory loss, and even dementia (as in pellagra).

Improves Skin Health

Vitamin B3 for skin reduces redness, inflammation, and sun damage. Niacinamide is often used in skincare products to treat acne, fine lines, and skin discoloration.

Reduces Inflammation and Supports Immunity

Niacin helps regulate inflammatory responses and strengthens immune defenses, which is essential for fighting infections.

Improve Sexual Health

Some studies, including “Niacin Therapy Improves Erectile Function in Men with Dyslipidemia” published in The Journal of Sexual Medicine, suggest that niacin benefits sexually by improving blood flow. The research found that daily niacin supplementation improved erectile function in men with moderate to severe erectile dysfunction related to poor circulation

Vitamin B3 Foods 

Getting enough niacin from your diet is the safest and most effective way to maintain healthy levels. Vitamin B3 foods are widely available and can be easily added to your daily meals. These foods not only support energy production but also help keep your skin, heart, and brain in good condition. 

Below is a list of some of the richest natural sources of vitamin B3: 

Food Source	Niacin Content (mg per 100g)
Chicken breast	14.8 mg
Tuna	18.8 mg
Turkey	11.8 mg
Beef liver	16.5 mg
Salmon	8.5 mg
Peanuts	12.1 mg
Whole grains	5–8 mg
Fortified cereals	15–20 mg
Legumes	2–3 mg

Recommended Dietary Allowances (RDA) for Vitamin B3 (Niacin)

The vitamin B3 dosage for adults depends on age, gender, and life stage. According to the National Institutes of Health (NIH) Office of Dietary Supplements, the Recommended Dietary Allowance (RDA) ensures you get enough niacin to support energy production, brain health, and overall body functions.

Life Stage	Recommended Amount	Description
Birth to 6 months	2 mg	Supports rapid growth and brain development in newborns.
Infants 7–12 months	4 mg NE	Helps in energy production and healthy digestion during infancy.
Children 1–3 years	6 mg NE	Supports physical and cognitive development in toddlers.
Children 4–8 years	8 mg NE	Aids energy metabolism and strong immune function in early school years.
Children 9–13 years	12 mg NE	Important for active growth, learning, and energy needs.
Teen boys 14–18 years	16 mg NE	Meets higher energy demands during puberty and muscle development.
Teen girls 14–18 years	14 mg NE	Supports hormonal changes and reproductive health.
Adult men 19+years	16 mg NE	Maintains metabolism, heart health, and brain function.
Adult women19+ years	14 mg NE	Supports daily energy needs, skin health, and nervous system.
Pregnant teens and women	18 mg NE	Essential for fetal growth and healthy pregnancy.
Breastfeeding teens and women	17 mg NE	Supports milk production and maternal recovery.

NE = Niacin equivalents, which include niacin from food and tryptophan conversion. 

For therapeutic uses such as cholesterol management, much higher doses (500–2000 mg/day) may be prescribed by a doctor. These therapeutic doses are supported by research, including “Niacin in Cardiovascular Disease Prevention: Current State of Affairs,” published in Current Atherosclerosis Reports. However, such high doses should only be taken under medical supervision due to possible side effects like liver damage and blood sugar changes.

Tolerable Upper Intake Levels (ULs) for Vitamin B3 (Niacin) 

The UL is the maximum daily amount unlikely to cause harmful side effects for most people. It applies to supplemental niacin (nicotinic acid) and fortified foods, not naturally occurring niacin in whole foods. 

Ages	Upper Limit	Description
Birth to 12 months	Not established	Safety levels not determined for this age group.
Children 1–3 years	10 mg	Exceeding this may cause flushing and discomfort.
Children 4–8 years	15 mg	High doses may cause stomach irritation.
Children 9–13 years	20 mg	Avoid long-term excess to prevent side effects.
Teens 14–18 years	30 mg	Large amounts may lead to skin flushing and liver strain.
Adults 19+ years	35 mg	Higher doses should be under medical supervision only.

Vitamin B3 Tablets and Supplements

If your diet does not provide enough niacin, a vitamin B3 supplement can help you meet your daily needs. These supplements are available in different forms and strengths to support various health goals, such as improving cholesterol, boosting energy, or enhancing skin health.

Popular vitamin B3 tablet name options include:

• Niacin 500 mg (Extended Release) – Often prescribed for cholesterol management under medical supervision.
• Niacinamide 500 mg – Commonly used for skin health, reducing inflammation, and supporting joint health.
• Vitamin B-Complex (with B3 included) – Provides a balanced mix of all B vitamins for overall energy and nervous system support.

Tip: Always check the supplement label to see whether it contains nicotinic acid (best for cholesterol support) or niacinamide (better for skin and anti-inflammatory benefits).

Nicotinic Acid vs Niacinamide – Which Should You Choose? 

When taking a vitamin B3 supplement, it’s important to know that it comes in two main forms: nicotinic acid and niacinamide (nicotinamide). While both provide the same essential vitamin, they work differently in the body and are suited for different health goals. 

Below is a quick comparison to help you choose the right type for your needs: 

Feature	Nicotinic Acid	Niacinamide (Nicotinamide)
Main Benefit	Lowers LDL cholesterol and triglycerides, raises HDL cholesterol	Improves skin health, reduces inflammation, supports joint health
Common Uses	Cholesterol managementheart health	Skincareanti-inflammatory supportarthritis relief
Flushing Side Effect	Yes, can cause flushing and warmth	No flushing effect
Best For	People with high cholesterol (under doctor’s care)	People with skin issues or those sensitive to flushing
Food Sources	MeatFishPoultryFortified cereals	MeatFishPoultryLegumesNuts
Supplement Forms	Extended-release tabletsImmediate-release tablets	TabletsCapsulesTopical creams

Tip: Choose nicotinic acid if you need cholesterol improvement (with medical guidance) and niacinamide if your focus is on skin health or inflammation reduction. 

Vitamin B3 Deficiency and Pellagra

A lack of vitamin B3 in the diet can lead to pellagra, a serious disease caused by a deficiency of niacin (vitamin B3) and, in some cases, tryptophan—an amino acid the body can convert into niacin. It is more common in areas where diets are poor in protein or rely heavily on corn, which contains very little niacin. Pellagra is recognized by the “4 Ds”:

1. Dermatitis – A skin rash that worsens in sunlight, usually appearing on exposed areas like the hands, face, and neck. The skin may become rough, dark, and scaly.
2. Diarrhea – Digestive issues such as ongoing diarrhea, abdominal pain, and poor nutrient absorption.
3. Dementia – Mental changes including confusion, memory loss, mood swings, and in severe cases, hallucinations or complete mental decline.
4. Death – If left untreated, pellagra can be fatal.

If left untreated, pellagra can be fatal. Early treatment with a vitamin B3 supplement or increasing vitamin B3 foods such as poultry, fish, nuts, and whole grains usually leads to full recovery.

Faqs

Are niacin and B3 the same thing?

Yes, niacin is another name for vitamin B3, which includes nicotinic acid and niacinamide.

Is it Safe to Take 500mg of Niacin a Day?

While vitamin B3 supplements at 500 mg/day can be effective for certain medical conditions, such high doses carry risks such as flushing, liver toxicity, and glucose intolerance. It is only safe under professional guidance.

Why is niacin no longer recommended?

In some cholesterol guidelines, niacin is less recommended because newer drugs have fewer side effects. However, it is still useful in certain cases.

What are the neurological symptoms of pellagra?

Neurological symptoms of pellagra can include

• Depression
• Apathy
• Headaches
• Fatigue

In more severe cases, it can cause memory loss that may progress to aggressive, paranoid, or suicidal behaviors, as well as auditory and visual hallucinations.

How is pellagra treated?

According to the World Health Organization (WHO), pellagra is treated with 300 mg/day of nicotinamide, divided into smaller doses over 3–4 weeks. A B-complex vitamin supplement or yeast product is also recommended to correct possible deficiencies in other B vitamins.

How much vitamin B3 is recommended daily?

The daily recommended amount of vitamin B3 varies by age, gender, and life stage. For most healthy adults, including

• Men: 16 mg per day
• Women: 14 mg per day
• Pregnant women: 18 mg per day
• Breastfeeding women: 17 mg per day

Is Vitamin B3 safe?

Yes, when taken within the daily recommended amount (16 mg for men, 14 mg for women).

Is it safe to take 500mg of niacin a day?

No, A 500 mg daily dose of niacin is much higher than the recommended amount and should only be taken under medical supervision. While it may be prescribed for conditions like high cholesterol, it can cause side effects such as skin flushing, liver damage, and increased blood sugar.