What are the potential side effects of niacin. How does vitamin B3 affect cholesterol levels. Can niacin supplements help prevent heart disease. Is niacin beneficial for diabetes management. Does niacin play a role in osteoarthritis treatment. How does niacin impact skin health.

The Essentials of Vitamin B3: Niacin’s Role in Body Functions

Vitamin B3, commonly known as niacin, is a crucial component of the B-vitamin complex. It plays a vital role in various bodily functions, from energy production to hormone synthesis. Niacin exists in three forms: nicotinic acid, niacinamide (nicotinamide), and inositol hexanicotinate, each with distinct effects on the body.

As part of the B-complex family, niacin assists in:

• Converting carbohydrates into glucose for energy production
• Facilitating the utilization of fats and proteins
• Supporting liver health
• Maintaining healthy skin, hair, and eyes
• Ensuring proper nervous system function

Additionally, niacin contributes to the production of sex and stress-related hormones in the adrenal glands and other body parts. It also aids in improving circulation and has demonstrated anti-inflammatory properties.

Niacin Deficiency: Symptoms and Consequences

While niacin deficiency is rare in developed countries, it can occur, particularly in individuals with alcoholism. Mild deficiency symptoms include:

• Indigestion
• Fatigue
• Canker sores
• Vomiting
• Poor circulation
• Depression

Severe deficiency can lead to pellagra, a condition characterized by cracked, scaly skin, dementia, and diarrhea. Treatment typically involves a balanced diet and niacin supplementation.

Niacin’s Impact on Cholesterol Management

Since the 1950s, niacin has been utilized to address high cholesterol levels. How effective is niacin in managing cholesterol? Studies have shown that niacin can lower elevated LDL (bad) cholesterol and triglyceride levels in the blood. However, its use comes with potential side effects, some of which can be significant.

Side Effects of High-Dose Niacin

When taken in high doses, niacin can cause:

• Skin flushing
• Stomach upset (usually temporary)
• Headache
• Dizziness
• Blurred vision
• Increased risk of liver damage

Time-release formulations of niacin can reduce flushing, but long-term use may be associated with liver damage. Due to these risks, high-dose niacin should only be taken under medical supervision.

Niacin’s Potential in Cardiovascular Health

Research has explored niacin’s role in cardiovascular health, particularly in relation to atherosclerosis and heart disease. Can niacin help prevent heart attacks? Some studies suggest promising results:

• Men with existing heart disease who took niacin along with colestipol showed slower progression of atherosclerosis and experienced fewer heart attacks and deaths.
• Individuals with heart disease and high cholesterol taking niacin with simvastatin demonstrated a lower risk of first heart attack or stroke, as well as reduced mortality risk.
• Men taking niacin alone appeared to have a lower risk of experiencing a second heart attack, although it did not reduce the overall risk of death.

These findings indicate potential benefits of niacin in cardiovascular health management, but further research is needed to fully understand its efficacy and optimal use.

Niacin and Diabetes: A Complex Relationship

The relationship between niacin and diabetes is multifaceted and varies depending on the type of diabetes. How does niacin affect different types of diabetes?

Type 1 Diabetes

In type 1 diabetes, niacinamide may offer some protection to insulin-producing pancreatic cells, potentially slowing disease progression. However, research results have been mixed:

• One study found that high-dose niacinamide reduced the risk of type 1 diabetes in at-risk children.
• A larger study failed to demonstrate protective effects against developing type 1 diabetes.

More research is needed to clarify niacinamide’s role in type 1 diabetes prevention and management.

Type 2 Diabetes

Niacin’s effect on type 2 diabetes is more complex. While it can help lower high levels of fats and cholesterol often associated with type 2 diabetes, it may also raise blood sugar levels. This dual action presents a challenge in diabetes management. Individuals with diabetes should only take niacin under close medical supervision to monitor blood sugar levels carefully.

Exploring Niacin’s Potential in Osteoarthritis Treatment

Preliminary research has suggested that niacinamide may offer benefits for individuals with osteoarthritis. How might niacin help with arthritis symptoms? A study indicated potential improvements in:

• Joint mobility
• Reduction in the need for non-steroidal anti-inflammatory drugs (NSAIDs)

While these initial findings are promising, more extensive research is required to confirm niacinamide’s efficacy in osteoarthritis treatment and to establish optimal dosing and long-term safety profiles.

Niacin’s Potential Role in Neurological and Ocular Health

Research has explored niacin’s potential benefits in neurological and ocular health, particularly in relation to Alzheimer’s disease and cataracts. What do population studies reveal about niacin intake and these conditions?

Alzheimer’s Disease

Population studies have shown a correlation between higher dietary niacin intake and a lower risk of Alzheimer’s disease. However, it’s important to note that these studies focused on dietary niacin rather than supplementation. Further research is needed to determine if niacin supplements could offer similar protective effects against Alzheimer’s disease.

Cataracts

A large population study found that individuals with higher niacin intake in their diets had a reduced risk of developing cataracts. This suggests a potential protective role of niacin in ocular health, but more research is needed to establish causality and explore the potential benefits of niacin supplementation for cataract prevention.

Niacin and Skin Health: Potential Benefits and Considerations

Niacin plays a crucial role in maintaining healthy skin. How does niacin contribute to skin health? Its benefits include:

• Supporting skin cell growth and repair
• Enhancing skin barrier function
• Improving skin hydration
• Potentially reducing inflammation in skin conditions

While niacin is essential for skin health, it’s important to note that high doses of niacin supplements can cause skin flushing, a common side effect. This temporary redness and warmth, while generally harmless, can be uncomfortable for some individuals.

Topical Niacin Applications

Niacinamide, a form of niacin, is often used in topical skincare products. It has shown potential benefits in:

• Reducing fine lines and wrinkles
• Improving skin elasticity
• Reducing hyperpigmentation
• Helping manage acne

These topical applications typically don’t cause the flushing associated with oral niacin supplements, making them a popular choice in skincare routines.

Safety Considerations and Recommended Intake of Niacin

While niacin is an essential nutrient, it’s crucial to understand appropriate intake levels and potential risks associated with high doses. What are the recommended daily allowances for niacin?

Recommended Daily Allowance (RDA) for Niacin

The RDA for niacin varies by age and gender:

• Adults (19+ years): 14-16 mg for men, 14 mg for women
• Pregnant women: 18 mg
• Breastfeeding women: 17 mg

These amounts can typically be obtained through a balanced diet. Foods rich in niacin include:

• Poultry
• Fish
• Peanuts
• Fortified cereals
• Legumes

High-Dose Niacin Precautions

High doses of niacin, often used for therapeutic purposes, should only be taken under medical supervision due to potential side effects and interactions. What are the risks associated with high-dose niacin? Potential concerns include:

• Liver damage
• Increased blood sugar levels
• Interactions with other medications, particularly those used for cholesterol management
• Gastrointestinal distress
• Skin flushing and itching

Individuals with certain health conditions, such as liver disease, peptic ulcers, or diabetes, should exercise particular caution with niacin supplementation and consult their healthcare provider before use.

Niacin Interactions with Medications

Niacin can interact with various medications, potentially affecting their efficacy or increasing the risk of side effects. What medications might interact with niacin? Some examples include:

• Statins (cholesterol-lowering drugs)
• Diabetes medications
• Blood thinners
• Certain blood pressure medications

It’s crucial to inform your healthcare provider about all medications and supplements you’re taking to avoid potential interactions and ensure safe use of niacin.

Future Directions in Niacin Research

As our understanding of niacin’s role in health and disease continues to evolve, several areas of research show promise for future applications. What are some emerging areas of niacin research?

Niacin and Longevity

Recent studies have explored the potential role of niacin in promoting longevity and healthy aging. Researchers are investigating how niacin might influence cellular processes related to aging, such as DNA repair and mitochondrial function.

Niacin and Mental Health

Preliminary research suggests potential benefits of niacin in certain mental health conditions. Studies are exploring its role in:

• Depression
• Schizophrenia
• Anxiety disorders

While early results are intriguing, more research is needed to establish efficacy and safety in these applications.

Novel Niacin Formulations

Researchers are working on developing new niacin formulations that could provide the benefits of high-dose niacin with reduced side effects. These include:

• Extended-release formulations with improved safety profiles
• Combination therapies that leverage niacin’s effects with other compounds
• Targeted delivery systems for specific health applications

These advancements could potentially expand the therapeutic use of niacin while minimizing risks associated with high doses.

Niacin and Immune Function

Emerging research is exploring niacin’s role in immune function and its potential applications in managing inflammatory conditions. Studies are investigating how niacin might influence:

• Immune cell function
• Inflammatory pathways
• Autoimmune disorders

This research could open new avenues for using niacin in immune-related health conditions.

As research in these areas progresses, our understanding of niacin’s diverse roles in health and disease will continue to expand, potentially leading to new therapeutic applications and improved strategies for harnessing its benefits while minimizing risks.

Vitamin B3 (Niacin) Information | Mount Sinai

Inositol hexaniacinate; Niacin; Niacinamide; Nicotinamide; Nicotinic acid

Vitamin B3 is one of 8 B vitamins. It is also known as niacin (nicotinic acid) and has 2 other forms, niacinamide (nicotinamide) and inositol hexanicotinate, which have different effects from niacin.

All B vitamins help the body convert food (carbohydrates) into fuel (glucose), which the body uses to produce energy. These B vitamins, often referred to as B-complex vitamins, also help the body use fats and protein. B-complex vitamins are needed for a healthy liver, healthy skin, hair, and eyes, and to help the nervous system function properly.

Niacin also helps the body make various sex and stress-related hormones in the adrenal glands and other parts of the body. Niacin helps improve circulation, and it has been shown to suppress inflammation.

All the B vitamins are water-soluble, meaning that the body does not store them.

You can meet all of your body’s needs for B3 through diet. It is rare for anyone in the developed world to have a B3 deficiency. In the U.S., alcoholism is the main cause of vitamin B3 deficiency.

Symptoms of mild B3 deficiency include:

• Indigestion
• Fatigue
• Canker sores
• Vomiting
• Poor circulation
• Depression

Severe deficiency can cause a condition known as pellagra. Pellagra is characterized by cracked, scaly skin, dementia, and diarrhea. It is generally treated with a nutritionally balanced diet and niacin supplements. Niacin deficiency also causes burning in the mouth and a swollen, bright red tongue.

Very high doses of B3, available by prescription, have been studied to prevent or improve symptoms of the following conditions. However, at high doses niacin can be toxic. You should not take doses higher than the Recommended Daily Allowance (RDA) except under your doctor’s supervision. Researchers are trying to determine if inositol hexanicotinate has similar benefits without serious side effects. But results are inconclusive.

High cholesterol

Niacin, but not niacinamide, has been used since the 1950s to lower elevated LDL (bad) cholesterol and triglyceride (fat) levels in the blood. However, side effects can be unpleasant and even dangerous. High doses of niacin cause:

• Flushing of the skin
• Stomach upset (which usually subsides within a few weeks)
• Headache
• Dizziness
• Blurred vision
• An increased risk of liver damage

A time-release form of niacin reduces flushing. But long-term use is associated with liver damage. In addition, niacin can interact with other cholesterol-lowering medicines. You should not take niacin at high doses without your doctor’s supervision.

Atherosclerosis and heart disease

In one study, men with existing heart disease slowed down the progression of atherosclerosis by taking niacin along with colestipol. They experienced fewer heart attacks and deaths, as well.

In another study, people with heart disease and high cholesterol who took niacin along with simvastatin (Zocor) had a lower risk of having a first heart attack or stroke. Their risk of death was also lower. In another study, men who took niacin alone seemed to reduce the risk of having a second heart attack, although it did not reduce the risk of death.

Diabetes

In type 1 diabetes, the body’s immune system mistakenly attacks the cells in the pancreas that make insulin, eventually destroying them. Niacinamide may help protect those cells for a time. More research is needed.

Researchers have also looked at whether high-dose niacinamide might reduce the risk of type 1 diabetes in children at risk for the disease. One study found that it did. But another, larger study found it did not protect against developing type 1 diabetes. More research is needed.

The effect of niacin on type 2 diabetes is more complicated. People with type 2 diabetes often have high levels of fats and cholesterol in the blood. Niacin, often along with other medications, can lower those levels. However, niacin may also raise blood sugar levels, which is particularly dangerous for someone with diabetes. For that reason, if you have diabetes, you should take niacin only under the direction of your doctor, and you should be carefully monitored for high blood sugar.

Osteoarthritis

One preliminary study suggested that niacinamide may improve arthritis symptoms, including increasing joint mobility and reducing the amount of non-steroidal anti-inflammatory drugs (NSAIDs) needed. More research is needed.

Other

Alzheimer disease: Population studies show that people who get higher levels of niacin in their diet have a lower risk of Alzheimer disease. No studies have evaluated niacin supplements, however.

Cataracts: One large population study found that people who got a lot of niacin in their diets had a lower risk of developing cataracts.

Skin conditions: Researchers are studying topical forms of niacin as treatments for rosacea, aging, and prevention of skin cancer, although it is too early to know whether it is effective.

Although there is no evidence that it helps treat any of these conditions, researchers are also studying the use of vitamin B3 in treating:

• ADHD
• Migraines
• Dizziness
• Depression
• Motion sickness
• Alcohol dependence

Dietary Sources

The best food sources of vitamin B3 are:

• Beets
• Brewer’s yeast
• Beef liver
• Beef kidney
• Fish
• Salmon
• Swordfish
• Tuna
• Sunflower seeds
• Peanuts

Bread and cereals are usually fortified with niacin. In addition, foods that contain tryptophan, an amino acid the body coverts into niacin, include poultry, red meat, eggs, and dairy products.

Available Forms

Vitamin B3 is available in several different supplement forms:

• Niacinamide
• Niacin
• Inositol hexaniacinate.

Niacin is available as a tablet or capsule in both regular and timed-release forms. The timed-release tablets and capsules may have fewer side effects than regular niacin. However, the timed-release versions are more likely to cause liver damage. Regardless of which form of niacin you are using, doctors recommend periodic liver function tests when using high doses (above 100 mg per day) of niacin.

How to Take It

Generally, high doses of niacin are used to control specific diseases. Such high doses must be prescribed by a doctor who will increase the amount of niacin slowly, over the course of 4 to 6 weeks. Take niacin with meals to avoid stomach irritation.

Daily recommendations for niacin in the diet of healthy individuals are:

Pediatric

• Infants, birth to 6 months: 2 mg (adequate intake)
• Infants, 7 months to 1 year: 4 mg (adequate intake)
• Children, 1 to 3 years: 6 mg (RDA)
• Children, 4 to 8 years: 8 mg (RDA)
• Children, 9 to 13 years: 12 mg (RDA)
• Boys, 14 to 18 years: 16 mg (RDA)
• Girls, 14 to 18 years: 14 mg (RDA)

Adult

• Men, 19 years and older: 16 mg (RDA)
• Women, 19 years and older: 14 mg (RDA)
• Pregnant women: 18 mg (RDA)
• Breastfeeding women: 17 mg (RDA)

Precautions

Because of the potential for side effects and interactions with medications, you should take dietary supplements only under the supervision of a knowledgeable health care provider. Side effects may include diarrhea, headache, stomach discomfort, and bloating.

High doses (50 mg or more) of niacin can cause side effects. The most common side effect is called “niacin flush,” which is a burning, tingling sensation in the face and chest, and red or flushed skin. Taking an aspirin 30 minutes prior to the niacin may help reduce this symptom.

At very high doses, used to lower cholesterol and treat other conditions, liver damage and stomach ulcers can occur. Your doctor will regularly check your liver function through a blood test.

People with a history of liver disease, kidney disease, or stomach ulcers should not take niacin supplements. Those with diabetes or gallbladder disease should do so only under the close supervision of their doctors.

Stop taking niacin or niacinamide at least 2 weeks before a scheduled surgery.

Niacin and niacinamide may make allergies worse by increasing histamine.

People with low blood pressure should not take niacin or niacinamide because they may cause a dangerous drop in blood pressure. DO NOT take niacin if you have a history of gout.

People with coronary artery disease or unstable angina should not take niacin without their doctor’s supervision, as large doses can raise the risk of heart rhythm problems.

Taking any one of the B vitamins for a long period of time can result in an imbalance of other important B vitamins. For this reason, you may want to take a B-complex vitamin, which includes all the B vitamins.

Possible Interactions

Because of its impact on the liver, vitamin B3 can interact with several medications. If you are currently taking medications, or regularly drink alcohol, you should not use niacin without talking to your health care provider first. Below is a partial list of medications that may interact with vitamin B3.

Antibiotics, tetracycline: Niacin should not be taken at the same time as the antibiotic tetracycline because it interferes with the absorption and effectiveness of this medication. All vitamin B complex supplements act in this way and should be taken at different times from tetracycline.

Aspirin: Taking aspirin before taking niacin may reduce flushing from niacin. But take it only under your doctor’s supervision.

Anti-seizure medications: Phenytoin (Dilantin) and valproic acid (Depakote) may cause niacin deficiency in some people. Taking niacin with carbamazepine (Tegretol) or mysoline (Primidone) may increase levels of these medications in the body.

Anticoagulants (blood thinners): Niacin may make the effects of these medications stronger, increasing the risk of bleeding.

Blood pressure medications, alpha-blockers: Niacin can make the effects of medications taken to lower blood pressure stronger, leading to the risk of low blood pressure.

Cholesterol-lowering medications: Niacin binds the cholesterol-lowering medications known as bile-acid sequestrants and may make them less effective. For this reason, niacin and these medications should be taken at different times of the day. Bile-acid sequestrants include colestipol (Colestid), colesevelam (Welchol), and cholestyramine (Questran).

Statins: Some scientific evidence suggests that taking niacin with simvastatin (Zocor) appears to slow the progression of heart disease. However, the combination may also increase the likelihood for serious side effects, such as muscle inflammation or liver damage.

Diabetes medications: Niacin may increase blood sugar levels. People taking insulin, metformin (Glucophage), glyburide (Dibeta, Micronase), glipizide (Glucotrol), or other medications used to treat high blood glucose levels should monitor their blood sugar levels closely when taking niacin supplements.

Isoniazid (INH): INH, a medication used to treat tuberculosis, may cause a niacin deficiency.

Nicotine patches: Using nicotine patches with niacin may worsen or increase the risk of flushing associated with niacin.

These medications may lower levels of niacin in the body:

• Azathioprine (Imuran)
• Chloramphenicol (Chloromycetin)
• Cycloserine (Seromycin)
• Fluorouracil
• Levodopa and carbidopa
• Mercaptopurine (Purinethol)

Supporting Research

AIM-HIGH Investigators. The role of niacin in raising high-density lipoprotein cholesterol to reduce cardiovascular events in patients with atherosclerotic cardiovascular disease and optimally treated low-density lipoprotein cholesterol Rationale and study design. The Atherothrombosis Intervention in Metabolic syndrome with low HDL/high triglycerides: Impact on Global Health outcomes (AIM-HIGH). Am Heart J. 2011 Mar;161(3):471-477.e2.

Bissett DL, Oblong JE, Berge CA, et al. Niacinamide: A B vitamin that improves aging facial skin appearance. Dermatol Surg. 2005;31:860-865; discussion 865.

Boden WE, Sidhu MS. Toth PP. The therapeutic role of niacin in dyslipidemia management. J Cardiovasc Pharmacol Ther. 2014;19(2):141-58.

Brown BG, Zhao XQ, Chalt A, et al. Simvastatin and niacin, antioxidant vitamins, or the combination for the prevention of coronary disease. N Engl J Med. 2001;345(22):1583-1592.

Cumming RG, Mitchell P, Smith W. Diet and cataract: the Blue Mountains Eye Study. Ophthalmology. 2000;107(3):450-456.

Draelos ZD, Ertel K, Berge C, et al. Niacinamide-containing facial moisturizer improves skin barrier and benefits subjects with rosacea. Cutis. 2005;76:135-141.

Elam M, Hunninghake DB, Davis KB, et al. Effects of niacin on lipid and lipoprotein levels and glycemic control in patients with diabetes and peripheral arterial disease: the ADMIT study: a randomized trial. Arterial Disease Multiple Intervention Trial. JAMA. 2000;284:1263-1270.

Garcia-Closas R. et al. Food, nutrient and heterocyclic amine intake and the risk of bladder cancer. Eur J Cancer. 2007;43(11):1731-1740.

Ginsberg HN, reyes-Soffer G. Niacin: a long history, but a questionable future. Curr Opin Lipidol. 2013;24(6):475-9.

Goldberg A, Alagona P, Capuzzi DM, et al. Multiple-dose efficacy and safety of an extended-release form of niacin in management of hyperlipidemia. Am J Cardiol. 2000;85:1100-1105.

Guyton JR. Niacin in cardiovascular prevention: mechanisms, efficacy, and safety. Curr Opin Lipidol. 2007 Aug;18(4):415-420.

Jacques PF, Chylack LT Jr, Hankinson SE, et al. Long-term nutrient intake and early age related nuclear lens opacities. Arch Ophthalmol. 2001;119(7):1009-1019.

Jones KW. Do patients on statins also need niacin? JAAPA. 2013;26(7):9-10.

Kuzniarz M, Mitchell P, Cumming RG, Flood VM. Use of vitamin supplements and cataract: the Blue Mountains Eye Study. Am J Ophthalmol. 2001;132(1):19-26.

Mittal MK, Florin T, Perrone J, Delgado JH, Osterhoudt KC. Toxicity from the use of niacin to beat urine drug screening. Ann Emerg Med. 2007;50(5):587-590.

Nutrients and Nutritional Agents. In: Kastrup EK, Hines Burnham T, Short RM, et al, eds. Drug Facts and Comparisons. St. Louis, MO: 2000;4-5.

Raja R, Thomas JM, Greenhill-Hopper M, Ley SV, Almeida Paz FA. Facile, one-step production of niacin (vitamin B3) and other nitrogen-containing pharmaceutical chemicals with a single-site heterogeneous catalyst. Chemistry. 2008;14(8):2340-2348.

Sahebkar A. effect of niacin on endothelial function: a systematic review and meta-analysis of randomized controlled trials. Vasc Med. 2014;19(1):54-66.

Sanyal S, Karas RH, Kuvin JT. Present-day uses of niacin: effects on lipid and non-lipid parameters. Expert Opin Pharmacother. 2007 Aug;8(11):1711-17.

Song WL, FitzGerald GA. Niacin, an old drug with a new twist. J Lipid Res. 2013;54(10):2486-94.

Surjana D. Damian DL. Nicotinamide in dermatology and photoprotection. Skinmed. 2011;9(6):360-365.

Torkos S. Drug-nutrient interactions: a focus on cholesterol-lowering agents. Int J Integrative Med. 2000;2(3):9-13.

Villines TC, Kim AS, Gore RS, Taylor AJ. Niacin: the evidence, clinical use, and future directions. Curr Atheroscler Rep. 2012;14(1):49-59.

Wolerton: Comprehensive Dermatalogic Drug Therapy. 2nd ed. Philadelphia, PA: Elsevier Saunders; 2007.

Zhang XM, Jing YP, Jia MY, Zhang L. Negative transcriptional regulation of inflammatory genes by group B3 vitamin nicotinamide. Mol Biol Rep. 2012;39(12):1036-1071.

Zhao H, Yang X, Zhou R, Yang Y. Study on vitamin B1, vitamin B2 retention factors in vegetables. Wei Sheng Yan Jiu. 2008;37(1):92-96.

Niacin (Vitamin B3) : Benefits, Dosage, Sources, Risks

Written by R. Morgan Griffin

In this Article

• Why do people take niacin?
• How much niacin should you take?
• Can you get niacin naturally from foods?
• What are the risks of taking niacin?

Having enough niacin, or vitamin B3, in the body is important for general good health. As a treatment, higher amounts of niacin can improve cholesterol levels.

As a cholesterol treatment, there are good studies showing that niacin can boost levels of good HDL cholesterol and lower triglycerides. Niacin also modestly lowers bad LDL cholesterol. It’s sometimes prescribed in combination with statins for cholesterol control, such as rosuvastatin (Crestor, Ezallor), simvastatin (Flolipid, Zocor), fluvastatin (Lescol), atorvastatin (Lipitor) and pravastatin (Pravachol).

However, niacin is only effective as a cholesterol treatment at fairly high doses. These doses could pose risks, such as liver damage, gastrointestinal problems, or glucose intolerance. So don’t treat yourself with over-the-counter niacin supplements. Instead, get advice from your health care provider, who can prescribe FDA-approved doses of niacin instead if recommended.

In addition, niacin is an FDA-approved treatment for pellagra, a rare condition that develops from niacin deficiency.

Since niacin can be used in different ways, talk to your health care provider about the best dosage for you.

Everyone needs a certain amount of niacin — from food or supplements — for the body to function normally. This amount is called the dietary reference intake (DRI), a term that is replacing the older and more familiar RDA (recommended daily allowance). For niacin, the DRIs vary with age and other factors and are given in milligrams of niacin equivalents: 

• Children: between 2-16 milligrams daily, depending on age
• Men: 16 milligrams daily
• Women: 14 milligrams daily
• Women (pregnant): 18 milligrams daily
• Women (breastfeeding): 17 milligrams daily
• Maximum daily intake for adults of all ages: 35 milligrams daily

Most people can get the amount of niacin they need by eating a healthy diet.

If your doctor prescribes niacin, you might want to take it with food. This can prevent upset stomach. To reduce flushing — a harmless but uncomfortable side effect of niacin that describes redness and warmth in the face and neck — your health care provider might recommend taking niacin along with aspirin and avoiding alcohol and spicy foods.

Niacin occurs naturally in many foods, including greens, meat, poultry, fish, and eggs, although in a fraction of the dose shown to achieve changes in cholesterol. Many products are also fortified with niacin during manufacturing.

• Side effects. Niacin can cause flushing, especially when you first begin taking it. Your health care provider will probably suggest increasing the dose slowly to reduce this problem. They might also offer a time-release prescription formulation to control flushing. Niacin can cause upset stomach and diarrhea. However, all of these side effects tend to fade over time.
• Risks. Niacin does have risks. It can cause liver problems, stomach ulcers, changes to glucose levels, muscle damage, low blood pressure, heart rhythm changes, and other issues. People with any health condition including liver or kidney disease, diabetes, high blood pressure, or cardiovascular problems need to talk to a doctor before using niacin supplements. Do not treat high cholesterol on your own with over-the-counter niacin supplements.
• Interactions. If you take any medicines or supplements regularly, talk to your doctor before you start using niacin supplements. They could interact with medicines like diabetes drugs, blood thinners, anticonvulsants, blood pressure medicines, thyroid hormones, and antibiotics as well as supplements like ginkgo biloba and some antioxidants. Alcohol might increase the risk of liver problems. Though niacin is often used along with statins for high cholesterol, this combination may increase the risk for side effects. Get advice from your healthcare provider.

At the low DRI doses, niacin is safe for everyone. However, at the higher amounts used to treat medical conditions, it can have risks. For that reason, children and women who are pregnant or breastfeeding should not take niacin supplements in excess of the DRI unless it’s recommended by a doctor. 

People with uncontrolled gout should also not take niacin supplements.

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uses, side effects, warnings on use, health benefits and harms

Nicotinic acid (niacin) is a water-soluble vitamin, belongs to the family of B vitamins, which is found in many tissues of animals and plants, has antihyperlipidemic activity. Niacin is converted to its active form, niacinamide, which is a component of the coenzymes nicotinamide adenine dinucleotide (NAD) and its phosphate form, NADP. These coenzymes play an important role in tissue respiration and the metabolism of glycogen, lipids, amino acids, proteins, and purine. Although the exact mechanism of action by which nicotinic acid lowers cholesterol levels is not well understood, this substance may act by inhibiting very low density lipoprotein (VLDL) synthesis, inhibiting the release of free fatty acids from adipose tissue, increasing lipoprotein lipase activity, and decreasing hepatic synthesis. VLDL-C and LDL-C.

Niacin, also known as nicotinic acid and vitamin B3, is a water-soluble, essential B vitamin that, when given in high doses, is effective in lowering low-density lipoprotein (LDL) cholesterol and increasing high-density lipoprotein (HDL) cholesterol, due to which this remedy acquires unique values ​​in the treatment of dyslipidemia. Niacin can cause mild to moderate elevations in serum aminotransferase levels, and high doses of certain forms of niacin are associated with clinically apparent, acute liver injury that can be both severe and fatal.

Niacin (nicotinic acid) is used to prevent and treat niacin deficiency (pellagra). Niacin deficiency can result from certain medical conditions (eg, alcohol abuse, malabsorption syndrome, Hartnup’s disease), poor diet, or long-term use of certain medications (eg, isoniazid).

Products containing vitamin B3

• avocado
• broccoli
• tomatoes
• mushrooms
• asparagus
• carrots
• rice
• legumes
• spinach
• sweet potato

Niacin deficiency can cause diarrhea, confusion (dementia), redness/swelling of the tongue, and scaling of hard red skin. Nicotinic acid helps support the body’s ability to produce and break down natural compounds (metabolism) needed for good health. Niacinamide (nicotinamide) is another form of vitamin B3, but it does not work in the same way as niacin.

Side effects of niacin use

Face and neck irritation, headache, itching, burning, sweating, chills or tingling may occur within 20 minutes to 4 hours after taking this drug. Irritation may continue for several hours. These effects should fade or fade as your body adjusts to the medication. Indigestion, heartburn, nausea, vomiting, and diarrhea may also occur. If any of these effects persist or worsen, tell your doctor or pharmacist immediately.

Veterinary Niacin

Like most animals, dogs can synthesize a certain amount of niacin from the essential amino acid tryptophan. The tryptophan metabolite can be formed in one of two ways: it can be formed by picolinic carboxylase, or it can be used to produce nicotinamide. Cats, unlike dogs, are not able to synthesize significant amounts of niacin from tryptophan because they have a very high activity of the enzyme picolinic carboxylase, which leads to the rapid catabolism of tryptophan. Thus, cats require a diet of pre-prepared niacin.

Dietary sources of nicotinic acid

Niacin occurs naturally in meat and legumes. Dietary niacin is commonly found in the form of nicotinic acid in plant materials, and as NAD or NADP in animal materials. Some wholegrain cereals, such as corn and sorghum, have a relatively high niacin content, but in these products, niacin is concentrated in the seed and germ layers and has poor bioavailability (i.e., bound within the cell), making the feed a poor source of dietary niacin. Niacin is also sensitive to heat breakdown and commercial feed additives are needed to keep it stable.

Diagnosis of niacin deficiency

Diagnosis of niacin deficiency can be made using the nicotinamide test, which measures urinary excretion of niacin metabolites, the test itself takes place in veterinary control laboratories. Diagnosis is also made by clinical signs, appropriate deficiency and dietary assessment.

The role of nicotinic acid in the animal body

Vitamin B3 – nicotinamide, plasma (Vitamin PP, niacin, Vitamin B3 – Nicotinamide, Niacinamide, plasma)

Method of determination
HPLC-MS (High Performance Liquid Chromatography with Mass Selective Detection).

Test material
Blood plasma (EDTA)

Synonyms: Nicotinic acid; Vitamin PP; Antipellagric factor; 3-pyridinecarboxylic acid.

Niacin; Vitamin B3; Nicotinicacid; Vitamin PP; Pyridine-3-carboxylicacid; 3-pyridinecarboxylicacid; Apelagrin; Pellagrin.

Brief description of the analyte Vitamin B3 – nicotinamide

Vitamin B3 includes two main forms – nicotinamide and nicotinic acid. During metabolic processes in the body, they are converted into nicotinamide adenine dinucleotide (NAD, nicotinamide adenine dinucleotide – NAD) and nicotinamide adenine dinucleotide phosphate (NADP, nicotinamide adenine dinucleotide phosphate – NADP) – coenzymes of many redox reactions that are vital for cellular metabolism.

Nicotinamide is important for the development and functioning of the central nervous system (CNS). Nicotinamide is believed to play an important role in protecting neurons from traumatic injury, ischemia, and stroke, and may be involved in the pathogenesis of the three most common neurodegenerative conditions: Alzheimer’s, Parkinson’s, and Huntington’s diseases. The key factor here is the bioavailability of nicotinamide, a low concentration of which can lead to neurological deficits and dementia, and a high concentration can lead to potential neurotoxicity. B3 deficiency in its classical form is manifested by pellagra, and one of the common names for this vitamin “PP” comes from pellagra prevention – preventing pellagra. Clinical manifestations of this disease include bilateral symmetrical dermatitis on areas of the skin exposed to sunlight; extensive inflammation of the mucous membranes, manifested by diarrhea, achlorhydria, glossitis, stomatitis, vaginitis; mental manifestations, including fatigue, insomnia, apathy, in severe cases, encephalopathy with disorientation, hallucinations, memory loss, psychosis and dementia.

The main dietary sources of vitamin B3 are foods containing yeast, lean meats, liver, and poultry. Smaller amounts of this vitamin (but sufficient to avoid deficiency) are found in milk, various green leafy vegetables, and canned salmon. In some plant foods, especially in cereals (corn, wheat), niacin is associated with peptides and sugars and is less available for absorption. Up to two-thirds of the required amount of vitamin B3 in adults can be formed in the body itself through the metabolism of tryptophan.

Nutritional deficiency of B3 is associated with a lack of protein food and is rare in developed countries, it can more often occur with a predominance of corn (maize) in the diet, which is poor in both niacin and tryptophan. Pellagra can sometimes be a secondary manifestation of the carcinoid syndrome, in which up to 60% of tryptophan is catabolized into 5-OH-tryptophan and serotonin; and Hartnup’s disease, a genetic disorder associated with malabsorption of amino acids, including tryptophan.

Vitamin deficiency can be caused by alcoholism, the action of certain drugs. A complicating factor may be a deficiency of vitamins B2, B6 and iron, which are involved in the conversion of tryptophan to niacin.

What is the purpose of determining the level of vitamin B3 in the blood?

The test is used to assess the status of vitamin B3 in the body.

Vitamin B3 preparations are used in medical practice, including nicotinamide, in the treatment of pellagra, carcinoid syndrome, Hartnup’s disease, nicotinic acid – in lipid-lowering therapy, using the range of its effects on lipid metabolism.