What are the potential side effects of niacin. How does vitamin B3 affect cholesterol levels. Can niacin supplementation benefit heart health. Is niacin effective for managing diabetes. How does vitamin B3 impact skin conditions.

The Essentials of Vitamin B3: Functions and Forms

Vitamin B3, also known as niacin, is a crucial member of the B-complex vitamin family. It plays a vital role in various bodily functions, including energy production, hormone synthesis, and maintaining healthy skin, hair, and eyes. Niacin exists in three primary forms: nicotinic acid, niacinamide (nicotinamide), and inositol hexanicotinate. Each form has distinct effects on the body, making it essential to understand their differences when considering supplementation or medical use.

Are all forms of vitamin B3 created equal? While they share the same core nutrient, their impacts on the body can vary significantly:

• Nicotinic acid: Known for its cholesterol-lowering effects
• Niacinamide: Often used in skincare and for its potential benefits in diabetes management
• Inositol hexanicotinate: A form that may offer similar benefits to nicotinic acid with potentially fewer side effects

Niacin’s Role in Metabolism and Overall Health

Niacin is integral to the body’s metabolic processes, particularly in converting food into usable energy. It assists in the breakdown of carbohydrates, fats, and proteins, ensuring optimal nutrient utilization. Beyond its metabolic functions, niacin contributes to the production of stress-related hormones in the adrenal glands and supports proper nervous system function.

Does niacin affect circulation? Indeed, one of niacin’s notable benefits is its ability to improve circulation. This improvement is partly due to its vasodilating properties, which can lead to the infamous “niacin flush” – a temporary reddening and warming of the skin that some people experience when taking high doses of nicotinic acid.

Anti-inflammatory Properties of Niacin

Research has shown that niacin possesses anti-inflammatory properties. This characteristic makes it a subject of interest in studies related to various inflammatory conditions. The mechanism behind niacin’s anti-inflammatory effects involves its ability to modulate certain inflammatory pathways in the body, potentially offering therapeutic benefits for conditions associated with chronic inflammation.

Recognizing Niacin Deficiency: Symptoms and Causes

While niacin deficiency is rare in developed countries, it can occur, particularly in individuals with certain risk factors. Alcoholism remains the primary cause of vitamin B3 deficiency in the United States. Understanding the symptoms of mild to severe niacin deficiency is crucial for early detection and treatment.

How can you identify a mild niacin deficiency? Look for these common signs:

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

In severe cases, niacin deficiency can lead to a condition called pellagra, characterized by the “3 Ds”: dermatitis, diarrhea, and dementia. Pellagra also often presents with a swollen, bright red tongue and a burning sensation in the mouth. Treatment typically involves a balanced diet rich in niacin and supplementation under medical supervision.

Niacin and Cholesterol Management: Benefits and Risks

Since the 1950s, niacin has been used as a treatment for high cholesterol levels. Specifically, nicotinic acid has shown effectiveness in lowering LDL (bad) cholesterol and triglycerides while raising HDL (good) cholesterol. However, the use of high-dose niacin for cholesterol management comes with potential side effects and risks that need careful consideration.

What are the common side effects of high-dose niacin therapy? Patients may experience:

• Flushing of the skin (often intense and uncomfortable)
• Stomach upset
• Headache
• Dizziness
• Blurred vision

More concerning is the increased risk of liver damage associated with long-term use of high-dose niacin. Time-release formulations were developed to reduce flushing, but these may carry an even higher risk of liver damage. Due to these potential risks, niacin therapy for cholesterol management should only be undertaken under close medical supervision and in conjunction with regular liver function monitoring.

Niacin’s Potential in Cardiovascular Health

Beyond its cholesterol-lowering effects, niacin has been studied for its potential benefits in overall cardiovascular health. Several studies have explored its impact on atherosclerosis progression and cardiovascular events in individuals with existing heart disease.

Can niacin supplementation reduce the risk of heart attacks? Some research suggests it might. In one study, men with heart disease who took niacin along with colestipol experienced a slower progression of atherosclerosis and fewer heart attacks and deaths. Another study found that combining niacin with simvastatin (a common cholesterol-lowering medication) reduced the risk of first heart attacks and strokes in people with heart disease and high cholesterol.

These findings highlight the potential of niacin as part of a comprehensive approach to managing cardiovascular health. However, it’s crucial to note that niacin therapy, especially at high doses, should only be initiated under medical supervision due to potential side effects and interactions with other medications.

Niacin and Diabetes: A Complex Relationship

The relationship between niacin and diabetes is multifaceted and requires careful consideration. Research has explored the potential benefits of niacinamide in both type 1 and type 2 diabetes, but the results have been mixed and sometimes contradictory.

In type 1 diabetes, some studies have investigated whether niacinamide could help protect pancreatic cells from the autoimmune attack characteristic of the disease. While one study showed promise in reducing the risk of type 1 diabetes in at-risk children, a larger subsequent study failed to confirm this protective effect.

For type 2 diabetes, the situation is more complex. Niacin’s ability to lower cholesterol and triglyceride levels could be beneficial for many people with type 2 diabetes, who often struggle with lipid management. However, niacin can also raise blood sugar levels, which is particularly problematic for individuals with diabetes.

Should people with diabetes avoid niacin supplements? Not necessarily, but caution is warranted. If you have diabetes and are considering niacin supplementation, it’s crucial to do so only under the close supervision of a healthcare provider. Regular monitoring of blood sugar levels is essential to ensure that the potential benefits of niacin therapy outweigh the risks of blood sugar dysregulation.

Niacin’s Potential in Other Health Conditions

Research into niacin’s effects extends beyond cardiovascular health and diabetes. Several studies have explored its potential benefits in various other health conditions, though many of these areas require further investigation to draw definitive conclusions.

Osteoarthritis

Can niacinamide improve arthritis symptoms? A preliminary study suggested that niacinamide supplementation might benefit individuals with osteoarthritis. Participants reported improved joint mobility and a reduced need for non-steroidal anti-inflammatory drugs (NSAIDs). However, more extensive research is necessary to confirm these findings and establish optimal dosing guidelines.

Alzheimer’s Disease

Population studies have indicated a potential link between higher dietary niacin intake and a reduced risk of Alzheimer’s disease. While these observational findings are intriguing, no clinical trials have yet evaluated the effects of niacin supplementation on Alzheimer’s prevention or progression. This area remains a promising avenue for future research.

Cataracts

Does niacin intake affect cataract risk? One large population study found an association between higher dietary niacin levels and a lower risk of cataract development. This finding suggests a potential protective effect of niacin on eye health, but more research is needed to establish a causal relationship and determine if supplementation could offer similar benefits.

Skin Health

Niacinamide, in particular, has gained attention in the dermatology field for its potential benefits in various skin conditions. It has been studied for its effects on acne, rosacea, and signs of aging. Some research suggests that niacinamide may help improve skin barrier function, reduce inflammation, and even out skin tone.

How does niacinamide benefit the skin? It works through several mechanisms:

• Strengthening the skin barrier
• Reducing transepidermal water loss
• Improving skin elasticity
• Potentially reducing hyperpigmentation

These properties have made niacinamide a popular ingredient in many skincare products, from serums to moisturizers.

Safety Considerations and Potential Side Effects of Niacin

While niacin is an essential nutrient with numerous potential health benefits, it’s crucial to understand the safety considerations and potential side effects, especially when taken in high doses or as a supplement.

Common Side Effects

What are the most common side effects of niacin supplementation? The following are frequently reported, especially with high doses of nicotinic acid:

• Flushing (redness, warmth, and tingling of the skin)
• Itching
• Gastrointestinal discomfort (nausea, vomiting, diarrhea)
• Headache
• Dizziness

The flushing reaction, while harmless, can be intense and uncomfortable for some individuals. It typically subsides with continued use, and strategies such as taking the supplement with food or using extended-release formulations can help mitigate this effect.

Serious Side Effects and Risks

At very high doses, niacin can cause more serious side effects. These include:

• Liver damage
• Increased blood sugar levels
• Gout flare-ups
• Ulcers
• Irregular heartbeat

The risk of liver damage is particularly concerning with sustained high-dose niacin therapy. Regular liver function tests are essential for individuals taking high-dose niacin supplements or medications.

Interactions with Medications

Niacin can interact with various medications, potentially altering their effectiveness or increasing the risk of side effects. Some notable interactions include:

• Statins: Combining niacin with statins may increase the risk of muscle damage
• Diabetes medications: Niacin can interfere with blood sugar control
• Blood thinners: Niacin may enhance the effects of these medications
• Blood pressure medications: Niacin could potentiate their effects, leading to excessive blood pressure lowering

Due to these potential interactions, it’s crucial to consult with a healthcare provider before starting niacin supplementation, especially if you’re taking other medications.

Dietary Sources and Recommended Intake of Niacin

Meeting your niacin needs through diet is generally preferable to supplementation for most people. Niacin is widely available in various foods, making it relatively easy to obtain adequate amounts through a balanced diet.

Rich Dietary Sources of Niacin

What foods are high in niacin? Some excellent sources include:

• Poultry (chicken, turkey)
• Fish (tuna, salmon)
• Beef
• Peanuts and peanut butter
• Legumes
• Whole grains
• Fortified cereals

Additionally, the body can produce small amounts of niacin from the amino acid tryptophan, found in protein-rich foods like eggs and dairy products.

Recommended Daily Allowance (RDA)

The RDA for niacin varies by age and gender. For adults, the recommendations are:

• Men (19+ years): 16 mg/day
• Women (19+ years): 14 mg/day
• Pregnant women: 18 mg/day
• Breastfeeding women: 17 mg/day

These amounts are easily achievable through a balanced diet for most people. However, certain populations, such as vegetarians or individuals with specific health conditions, may need to pay extra attention to their niacin intake.

Supplementation Considerations

While dietary sources are generally sufficient, niacin supplements may be recommended in certain situations, such as for treating specific medical conditions or addressing severe deficiencies. However, it’s crucial to approach supplementation cautiously:

• Always consult with a healthcare provider before starting niacin supplementation
• Start with low doses and gradually increase if necessary
• Be aware of potential side effects and interactions with medications
• Regular monitoring may be necessary, especially for high-dose supplementation

Remember, more is not always better when it comes to vitamins and minerals. Excessive niacin intake, particularly from supplements, can lead to adverse effects and potential toxicity.

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.

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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.