Vitamin B3 (Niacin): Benefits, side effects, dosage, food, deficiency

Have you ever considered the impact of essential nutrients on your health and well-being? One such nutrient, Vitamin B3 or Niacin, is essential in several bodily functions, including transforming food into energy, maintaining skin health, and supporting the nervous system. 

Despite its significance, many people are unaware of how to optimize their intake of this vital nutrient. 

This guide will explore the benefits of Vitamin B3, its potential side effects, recommended dosages, natural food sources, and what happens when you’re deficient. 

With a focus on practical advice, you’ll gain the knowledge to make informed decisions about adding Vitamin B3 to your diet for optimal health.

What is Vitamin B3 or niacin?

Vitamin B3 is an important nutrient your body requires for proper functioning, but it cannot produce it independently.

It comes in three primary forms: nicotinic acid, niacinamide, and nicotinamide riboside. Each form has its benefits and roles within the body, from aiding metabolism to repairing DNA.

The discovery of Vitamin B3 dates back to the early 20th century when scientists were searching for a cure for pellagra, a disease prevalent in the southern United States [1]. 

Scientists discovered that a diet lacking certain nutrients, later known as niacin, was the root cause. 

This breakthrough highlighted the vital role of nutrients in preventing disease and maintaining overall health.

Vitamin B3 helps convert food into energy for cell function. Beyond its metabolic benefits, Vitamin B3 is essential for DNA repair and works to keep your skin and nervous system healthy. 

Its impact extends to lowering cholesterol levels, potentially reducing the risk of cardiovascular diseases.

What is the best form of vitamin B3 to take?

Vitamin B3 comes in three main forms: niacin (also known as nicotinic acid), nicotinamide, and nicotinamide riboside. 

Each form has unique benefits and uses, making it important to understand their differences to choose the right one for your health goals and needs.

Niacin (Nicotinic Acid)

Niacin is well-known to improve cholesterol levels by increasing HDL (good) cholesterol and reducing LDL (bad) cholesterol and triglycerides. It’s often used under medical supervision to help prevent cardiovascular disease [2]. 

However, niacin can cause “niacin flush,” a temporary but uncomfortable redness and warmth of the skin [2]. 

While generally harmless, this effect can be a consideration for those sensitive to or concerned about these symptoms.

Nicotinamide or niacinamide

Nicotinamide, another form of Vitamin B3, does not cause the flushing associated with niacin, making it a preferable option for those looking to avoid this side effect. 

This form is primarily used for its skin benefits, including reducing inflammation and improving conditions like acne [3]. It is also involved in DNA repair and supports the health of the nervous system.

Nicotinamide riboside (NR)

NR is a newer focus of research and is considered a promising supplement for boosting NAD+ (nicotinamide adenine dinucleotide) levels, a coenzyme involved in many metabolic processes [4]. 

Higher NAD+ levels have been linked to anti-aging effects, improved energy metabolism, and brain health. 

Due to its potential to increase NAD+ more effectively than other forms, nicotinamide riboside is gaining attention for its role in healthy aging and longevity.

Which Vitamin B3 should you take?

The choice between these forms of Vitamin B3 depends on your specific health goals, conditions, and how your body responds to each form. 

Niacin might be the preferred choice for improving cholesterol levels under the guidance of a healthcare professional. 

Nicotinamide could be better suited for those focusing on skin health and avoiding the flush. Nicotinamide riboside may be worth considering if you want anti-aging and cognitive benefits.

Before deciding on a form of Vitamin B3, it’s crucial to consult with your healthcare provider. They can offer personalized advice based on your health history, current conditions, and nutritional needs. 

Additionally, monitor your body’s response to the chosen form of Vitamin B3, as individual reactions can vary. 

With the proper guidance and careful consideration, you can effectively incorporate the most suitable form of Vitamin B3 into your health regimen.

Photograph: Nadiastep/Envato

What are the benefits of taking Vitamin B3?

Vitamin B3 is a key nutrient in promoting overall health and preventing chronic diseases. Adequate intake and a balanced diet can lead to significant health improvements, from enhanced heart and brain health to better skin and reduced arthritis symptoms.

1. Improves cholesterol levels

One of the most celebrated benefits of Vitamin B3, particularly in its nicotinic acid form, is its ability to improve cholesterol levels

It has been shown to increase HDL (high-density lipoprotein) cholesterol, also known as “good” cholesterol, which helps remove bad cholesterol from your bloodstream, reducing the risk of heart disease. 

Studies have found that nicotinic acid can significantly lower LDL (low-density lipoprotein) cholesterol and triglycerides, making it a valuable tool in managing cholesterol levels and preventing cardiovascular disease [5].

2. Contributes to brain health and function

Vitamin B3 also profoundly impacts brain health. It produces neurotransmitters essential for brain function, potentially improving cognitive abilities and reducing the risk of neurodegenerative diseases. 

There is growing evidence that niacin plays a role in protecting against Alzheimer’s disease and age-related cognitive decline [6], making adequate intake of this vitamin crucial for maintaining mental acuity.

3. Enhances skin health

For those seeking youthful, radiant skin, Vitamin B3 is a go-to nutrient. Niacinamide, a form of Vitamin B3, is widely recognized for its skin benefits, including reducing inflammation, redness, and hyperpigmentation [7]. 

It also helps to improve the skin’s barrier function, retaining moisture and protecting against pollutants and irritants. Regular intake of niacinamide can lead to visibly improved skin texture and tone.

4. Supports cardiovascular health

Beyond its cholesterol-lowering effects, Vitamin B3 supports cardiovascular health by aiding in the reduction of atherosclerosis and the buildup of plaque in the arteries, which can lead to heart disease [8]. 

Its vasodilating effects improve blood flow, reducing the risk of heart attacks and strokes.

5. Reduces symptoms of arthritis

People with arthritis may find relief with Vitamin B3 supplementation. Niacinamide has been shown to reduce inflammation and pain associated with arthritis, improving joint mobility [9]. While not a cure, it can be a valuable component of a comprehensive approach to managing arthritis symptoms.

Which food has the most vitamin B3?

Vitamin B3 can be obtained from various animal and plant-based foods. 

Animal sources of Vitamin B3

  • Chicken breast – One of the richest sources, chicken breasts provide a substantial amount of your daily niacin needs in a single serving.
  • Turkey – Especially lean cuts, are high in protein and a great source of Vitamin B3.
  • Beef – Particularly liver, which is packed with niacin as well as other vital nutrients.
  • Fish – Tuna and salmon are excellent choices, offering significant amounts of Vitamin B3 and omega-3 fatty acids for heart health.

Plant sources of Vitamin B3

  • Mushrooms – Particularly portobello and crimini, which are among the richest plant-based sources.
  • Green peas – A cup of fresh green peas provides a good portion of your daily niacin requirement.
  • Avocados – Not only a source of healthy fats but also a good way to add niacin to your diet.
  • Whole grains – Such as brown rice and barley, contain more niacin than their refined counterparts.

Comparison of niacin content

The niacin content can vary significantly among foods. For example, a 3-ounce serving of chicken breast offers about 11.4 mg of niacin, while the same amount of salmon provides around 8.5 mg. 

Comparatively, a cup of cooked brown rice has about 5.2 mg. This variability underscores the importance of a diverse diet to meet your nutritional needs.

How do you incorporate Vitamin B3 foods into your diet?

  1. Diversify your protein sources. Rotate between animal and plant sources to cover your niacin needs while keeping your meals interesting.
  2. Choose whole grains. Swap refined grains for whole grains in your meals for an added niacin boost.
  3. Snack on niacin-rich foods. To increase your daily intake, you can incorporate avocados and mushrooms into your snacks or meals.
  4. Be mindful of cooking methods. Some niacin can be lost in water when boiling foods. Opt for grilling, baking, or steaming to retain nutrients.

How much niacin should you take per day?

The RDAs vary based on age, gender, and life stage, reflecting the different needs of our bodies as we grow and change.

  • Infants – Up to 6 months, an adequate intake (AI) is set at 2 mg of niacin equivalents per day, reflecting the average intake in healthy, breastfed infants.
  • Children – As they grow, the requirement increases: 6 mg/day for ages 1-3, 8 mg/day for ages 4-8, and 12 mg/day for ages 9-13.
  • Adults – Men aged 14 and over should aim for 16 mg/day, while women aged 14 and up should aim for 14 mg/day.
  • Pregnant and breastfeeding women – The demands of pregnancy and breastfeeding increase the need for Vitamin B3 to 18 mg/day and 17 mg/day, respectively [2].

Maximum safe dosages

While Vitamin B3 is essential, there’s a threshold beyond which it can cause adverse effects, known as the Upper Intake Level (UL). 

For adults, the UL is set at 35 mg/day of nicotinic acid when taken as a supplement on an empty stomach, primarily to prevent the “niacin flush” — a temporary heat, itching, or redness of the skin [2]. 

Niacinamide, another form of Vitamin B3, does not cause this flushing but still adheres to the same UL due to potential liver damage at high intakes.

When and how to take Vitamin B3 supplements


If you’re taking Vitamin B3 supplements, consider doing so with meals to reduce the risk of stomach irritation and mitigate the flushing effect associated with nicotinic acid.


Choose between nicotinic acid and niacinamide based on your health goals and tolerance for potential side effects, under the guidance of a healthcare provider.


Always consult with a healthcare professional before starting any supplement regimen, especially if you are pregnant, breastfeeding, or managing health conditions. They can provide personalized advice based on your health status and nutritional needs.

What happens if Vitamin B3 is low?

Vitamin B3 is pivotal for maintaining optimal health due to its role in converting food into energy, DNA repair, and supporting the nervous system. 

However, not getting enough Vitamin B3 can lead to specific symptoms and signs, underscoring the importance of recognizing these early indicators to prevent more severe health issues.

Symptoms and signs of Vitamin B3 deficiency

The deficiency of Vitamin B3 can initially present as fatigue, headaches, and irritability, which could easily be overlooked or attributed to other common causes. As the deficiency progresses, more specific symptoms emerge, including:

  • Skin issues – Dermatitis, particularly in areas exposed to sunlight, can occur and is characterized by red, swollen, and cracked skin.
  • Digestive problems: Symptoms may include a bright red tongue, nausea, vomiting, constipation, or diarrhea, reflecting the impact of niacin deficiency on digestive health.
  • Mental health issues: Depression, apathy, and memory loss, indicating the crucial role of niacin in brain function.

These symptoms are early warnings, leading to more severe conditions like pellagra if the deficiency remains unaddressed. 

Pellagra is marked by the hallmark trio of dermatitis, diarrhea, and dementia, and in severe cases, can be life-threatening [2].

What causes Vitamin B3 deficiency?

Niacin deficiency can arise from various sources, fundamentally linked to inadequate intake or absorption of the vitamin:

  • Dietary insufficiency -: Limited access to niacin-rich foods, such as lean meats, fish, peanuts, and whole grains, primarily due to socioeconomic factors or dietary restrictions, can lead to deficiency.
  • Alcohol abuse – Excessive alcohol consumption impairs the absorption of niacin and other essential nutrients, significantly increasing the risk of deficiency.
  • Medical conditions – Certain health issues, including gastrointestinal disorders and some genetic conditions, can hinder niacin absorption or increase the body’s requirements for this nutrient.

Who is at risk of Vitamin B3 deficiency?

Despite the availability of niacin in various foods, certain groups are more susceptible to this deficiency due to dietary, lifestyle, and health-related factors.

Individuals with limited dietary diversity

Those who consume a diet with insufficient variety, especially diets lacking in fresh meats, fish, fortified grains, and vegetables, face a higher risk of niacin deficiency. 

This includes people with economic constraints, those following strict dietary restrictions without adequate nutritional planning, and individuals in regions where food diversity is limited.

People struggling with alcoholism

Alcohol abuse is a significant risk factor for niacin deficiency. Alcohol interferes with the absorption of niacin and other vital nutrients and increases the body’s nutritional needs, making it challenging for individuals struggling with alcoholism to maintain adequate levels of niacin.

Those with gastrointestinal disorders

Conditions that affect the absorption of nutrients, such as Crohn’s disease, ulcerative colitis, and celiac disease, can lead to a deficiency in niacin. These conditions impair the body’s ability to absorb niacin from food, increasing the risk of deficiency.

Individuals with certain genetic metabolic disorders

Rare genetic conditions, such as Hartnup disease, affect the body’s ability to absorb tryptophan, a precursor to niacin. People with these disorders are at a heightened risk of developing niacin deficiency.

People struggling with alcoholism

How do you prevent and manage Vitamin B3 deficiency?

Managing and preventing Vitamin B3 (niacin) deficiency involves strategic dietary planning and, in some cases, supplementation, ensuring that individuals receive adequate amounts of this crucial nutrient. 

By understanding the sources of niacin and the daily recommended intake, you can effectively guard against deficiency and its associated health risks.

1. Incorporate niacin-rich foods

Emphasize a diet that includes a variety of niacin-rich foods. Lean meats, poultry, fish, whole grains, legumes, nuts, seeds, and green vegetables are excellent sources. Diversifying your diet not only helps prevent niacin deficiency but also supports overall health.

2. Plan meals mindfully

Careful meal planning becomes essential for individuals with dietary restrictions or those following vegetarian or vegan diets. 

Plant-based sources of niacin, such as mushrooms, avocados, and peanuts, should be regularly included in meals to meet nutritional needs.

3. Understand bioavailability

The bioavailability of niacin varies between food sources. For example, niacin in animal products is more readily absorbed than in plant sources. Knowing this can help in planning meals that optimize niacin intake.

4. When necessary, consider supplements

In cases where dietary intake may not be sufficient due to lifestyle, health conditions, or alcohol dependency, niacin supplements can be an effective way to prevent deficiency. 

However, it’s important to consult with a healthcare provider before starting any supplementation to determine the appropriate dosage and to avoid the risk of over-supplementation.

5. Consume alcohol moderately

Since excessive alcohol intake can interfere with niacin absorption, moderating alcohol consumption is crucial for preventing niacin deficiency.

6. Address absorption issues

For those with health conditions that affect nutrient absorption, work with healthcare providers to manage your underlying condition. This may involve specific treatments or dietary adjustments to ensure adequate niacin intake.

7. Monitor regularly

Regular check-ups with a healthcare provider can help monitor niacin levels, especially for those at higher risk of deficiency. Be proactive about your health to allow for timely adjustments to diet or supplementation as needed.

What are the side effects of too much Vitamin B3?

While Vitamin B3 is essential for good health, it’s important to be aware that excessive intake can lead to side effects. 

Understanding these side effects and taking appropriate precautions can help you maintain the balance needed to reap the benefits of niacin without experiencing negative consequences.

Niacin flush

One of the most well-known side effects of high doses of niacin (particularly from supplements) is “niacin flush.” 

This condition is characterized by redness, warmth, itching, or tingling in the skin. The flush is usually harmless and temporary but can be uncomfortable for many individuals.

Liver toxicity

High doses of niacin have been associated with liver damage. This is more common with long-term use of high-dose niacin supplements. Symptoms of liver toxicity include jaundice, nausea, and elevated liver enzymes [10].

Gastrointestinal distress

Overconsumption of niacin can lead to gastrointestinal issues such as nausea, vomiting, and diarrhea. It can also cause abdominal pain and bloating.

Elevated blood sugar levels

Niacin can affect blood sugar levels, making it particularly important for individuals with diabetes to monitor their intake carefully [11]. High doses of niacin may increase blood sugar levels, potentially interfering with diabetes management.


Excessive niacin intake can lead to elevated levels of uric acid in the blood, potentially triggering gout attacks in susceptible individuals [12].

How do you prevent Vitamin B3 side effects?

Consult healthcare providers

Before adding a niacin supplement to your regimen, it’s crucial to consult with a healthcare provider. They can provide guidance on the appropriate dosage based on your health status and needs.

Following the recommended dietary allowances (RDAs) for niacin and not exceeding the upper intake levels (ULs) can help prevent adverse effects. The RDAs vary by age, gender, and physiological status.

Monitor for side effects

If you’re taking niacin supplements, especially in high doses, be vigilant about monitoring for any side effects. Reporting these to your healthcare provider can help manage your intake and mitigate risks.

Closing thoughts

Navigating the world of vitamins and nutrients can sometimes feel overwhelming, but understanding the significance of Vitamin B3 and its various forms brings us closer to optimizing our health. 

From supporting metabolism and enhancing skin health to potentially offering a pathway to longevity through nicotinamide riboside, the benefits of Vitamin B3 are wide-ranging. 

Consult your healthcare provider to tailor your intake, whether through diet or supplementation, and ensure you harness these benefits effectively. 

Remember, the goal is not just to prevent deficiencies but to thrive with vitality and well-being.


Vitamin B3 improves cholesterol levels, supports skin health, and enhances brain function. It plays a crucial role in converting food into energy and repairing DNA, contributing to overall health and well-being.

Is it safe to take B3 everyday?

It is safe to take Vitamin B3 daily within the recommended dietary allowances to support metabolic, skin health, and neurological functions. However, exceeding the recommended amounts without medical supervision can lead to adverse effects.

Who needs to take vitamin B3?

Vitamin B3 may be necessary for individuals with niacin deficiency, high cholesterol, or those seeking to improve skin health and cognitive function. It also benefits people at risk of deficiency due to dietary restrictions or certain medical conditions.

Can I take vitamin B3 with vitamin D?

Yes, you can take Vitamin B3 with Vitamin D, as they serve different bodily functions and do not interfere with each other’s absorption. Combining them can support overall health, including metabolic, bone, and immune system health.

Photograph: LightFieldStudios/Envato


The information included in this article is for informational purposes only. The purpose of this webpage is to promote broad consumer understanding and knowledge of various health topics. It is not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of your physician or other qualified health care provider with any questions you may have regarding a medical condition or treatment and before undertaking a new health care regimen, and never disregard professional medical advice or delay in seeking it because of something you have read on this website.