What are the potential side effects of niacin. How does vitamin B3 affect cholesterol levels. Can niacin supplementation help with various health conditions. What is the recommended daily allowance for vitamin B3. How does niacin deficiency manifest in the body.

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, from energy production to hormone synthesis. But what exactly does this essential nutrient do for our health?

Niacin comes in three main forms:

• Niacin (nicotinic acid)
• Niacinamide (nicotinamide)
• Inositol hexanicotinate

Each form has distinct effects on the body, making it essential to understand their differences when considering supplementation or addressing specific health concerns.

Key Functions of Vitamin B3

Vitamin B3 contributes to several crucial bodily processes:

• Converting carbohydrates into glucose for energy production
• Assisting in the metabolism of fats and proteins
• Supporting liver health
• Maintaining healthy skin, hair, and eyes
• Promoting proper nervous system function
• Aiding in the production of sex and stress-related hormones
• Improving circulation
• Suppressing inflammation

Given its wide-ranging impact on health, ensuring adequate vitamin B3 intake is crucial for overall well-being.

Niacin Deficiency: Symptoms and Consequences

While rare in developed countries, niacin deficiency can occur, particularly in individuals with alcoholism. Recognizing the signs of deficiency is crucial for timely intervention. What are the symptoms of mild niacin deficiency?

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

In severe cases, niacin deficiency can lead to a condition called pellagra. This serious health issue is characterized by:

• Cracked, scaly skin
• Dementia
• Diarrhea
• Burning sensation in the mouth
• Swollen, bright red tongue

Treatment for pellagra typically involves a nutritionally balanced diet and niacin supplements under medical supervision.

Niacin and Cholesterol Management: Benefits and Risks

One of the most well-known applications of niacin is its role in managing cholesterol levels. How does niacin affect cholesterol?

Since the 1950s, niacin (but not niacinamide) has been used to:

• Lower elevated LDL (bad) cholesterol
• Reduce triglyceride (fat) levels in the blood

While these effects can be beneficial for cardiovascular health, high-dose niacin supplementation comes with potential side effects:

• Flushing of the skin
• Stomach upset (usually temporary)
• Headache
• Dizziness
• Blurred vision
• Increased risk of liver damage

Time-release formulations of niacin can help reduce flushing, but long-term use may still pose a risk of liver damage. Due to these potential complications, high-dose niacin therapy should only be undertaken under medical supervision.

Niacin’s Potential in Cardiovascular Health

Beyond its effects on cholesterol, niacin has shown promise in addressing other aspects of cardiovascular health. What does research say about niacin’s impact on heart disease?

Several studies have explored niacin’s potential benefits:

• One study found that men with existing heart disease who took niacin along with colestipol slowed the progression of atherosclerosis and experienced fewer heart attacks and deaths.
• Another study showed that people with heart disease and high cholesterol who combined niacin with simvastatin (Zocor) had a lower risk of first heart attack or stroke, as well as a reduced risk of death.
• Research on men taking niacin alone suggested a reduced risk of second heart attack, although it did not affect overall mortality rates.

These findings highlight the potential of niacin as part of a comprehensive approach to cardiovascular health management. However, more research is needed to fully understand its long-term effects and optimal usage in different patient populations.

Niacin and Diabetes: A Complex Relationship

The relationship between niacin and diabetes is multifaceted, with potential benefits and risks depending on the type of diabetes and individual circumstances. How does niacin interact with different forms of diabetes?

Type 1 Diabetes

In type 1 diabetes, niacinamide may offer some protective effects:

• It may help protect pancreatic cells that produce insulin from immune system attack, potentially slowing disease progression.
• Research has explored whether high-dose niacinamide could reduce the risk of type 1 diabetes in at-risk children, with mixed results.

Type 2 Diabetes

The impact of niacin on type 2 diabetes is more complex:

• Niacin can help lower high levels of fats and cholesterol in the blood, which are common in type 2 diabetes.
• However, niacin may also raise blood sugar levels, which can be dangerous for diabetics.

Due to these potential complications, individuals with diabetes should only take niacin under close medical supervision and with careful monitoring of blood sugar levels.

Niacin’s Potential in Other Health Conditions

Research has explored niacin’s potential benefits in various other health conditions. What are some areas where niacin shows promise?

Osteoarthritis

A preliminary study suggested that niacinamide may improve arthritis symptoms by:

• Increasing joint mobility
• Reducing the need for non-steroidal anti-inflammatory drugs (NSAIDs)

However, more research is needed to confirm these potential benefits.

Alzheimer’s Disease

Population studies have shown a correlation between higher dietary niacin intake and a lower risk of Alzheimer’s disease. However, no studies have directly evaluated the effects of niacin supplements on Alzheimer’s prevention or treatment.

Cataracts

A large population study found that individuals with higher dietary niacin intake had a lower risk of developing cataracts. This suggests a potential protective effect of niacin on eye health, but more research is needed to establish a causal relationship.

Niacin Supplementation: Dosage and Safety Considerations

While niacin is essential for health, supplementation requires careful consideration. What should individuals know about niacin dosage and safety?

• The Recommended Daily Allowance (RDA) for niacin varies by age, sex, and life stage.
• Most people can meet their niacin needs through a balanced diet.
• High-dose niacin supplementation should only be undertaken under medical supervision due to potential side effects and interactions with other medications.
• Individuals with certain health conditions, such as liver disease or diabetes, should be particularly cautious with niacin supplementation.

When considering niacin supplementation, it’s crucial to consult with a healthcare provider to determine the appropriate dosage and form based on individual health needs and circumstances.

Dietary Sources of Niacin: Meeting Your Needs Naturally

For most individuals, obtaining adequate niacin through diet is preferable to supplementation. What are some rich dietary sources of niacin?

• Meat: Beef, pork, chicken, turkey
• Fish: Tuna, salmon, sardines
• Nuts and seeds: Peanuts, sunflower seeds
• Legumes: Lentils, beans
• Whole grains: Brown rice, whole wheat
• Fortified cereals and breads

Incorporating a variety of these foods into your diet can help ensure adequate niacin intake without the need for supplements. For vegetarians and vegans, particular attention to plant-based niacin sources is important to meet nutritional needs.

Niacin in Food Processing

It’s worth noting that niacin can be lost during food processing. How does food preparation affect niacin content?

• Milling of grains can remove significant amounts of niacin.
• Boiling foods can lead to niacin leaching into cooking water.
• Some cooking methods, like grilling or roasting, may help retain niacin content.

To maximize niacin intake from food, consider incorporating a variety of cooking methods and choosing whole, minimally processed foods when possible.

The Future of Niacin Research: Emerging Areas of Interest

As our understanding of niacin’s role in health continues to evolve, researchers are exploring new potential applications and forms of the vitamin. What are some emerging areas of niacin research?

Novel Formulations

Researchers are investigating new forms of niacin that may offer the benefits of high-dose therapy with fewer side effects. For example, inositol hexanicotinate is being studied as a potential alternative to traditional niacin formulations.

Niacin and Mental Health

Given niacin’s role in nervous system function, there is growing interest in its potential impact on mental health conditions. Some areas of exploration include:

• Depression
• Anxiety disorders
• Schizophrenia

While preliminary research is promising, more studies are needed to establish the efficacy and safety of niacin in these contexts.

Niacin and Longevity

Some researchers are investigating whether niacin and its derivatives could play a role in promoting longevity and healthy aging. This research focuses on niacin’s potential effects on:

• DNA repair mechanisms
• Cellular energy production
• Oxidative stress reduction

While these areas of research are exciting, it’s important to approach emerging findings with caution and wait for robust scientific evidence before drawing conclusions about niacin’s potential new applications.

Niacin Interactions: Understanding Potential Risks

As with any nutrient or medication, niacin can interact with other substances in ways that may affect its efficacy or safety. What are some important interactions to be aware of when considering niacin supplementation or high-dose therapy?

Medication Interactions

Niacin can interact with several types of medications, including:

• Statins: While niacin is sometimes used in combination with statins for cholesterol management, this combination can increase the risk of muscle damage and should be closely monitored.
• Diabetes medications: Niacin may interfere with blood sugar control, necessitating adjustments to diabetes medication dosages.
• Blood thinners: Niacin may enhance the effects of blood-thinning medications, potentially increasing the risk of bleeding.
• Blood pressure medications: Niacin can potentiate the effects of some blood pressure medications, potentially leading to excessive blood pressure lowering.

Alcohol Interactions

Combining high-dose niacin with alcohol consumption can increase the risk of liver damage. Individuals taking niacin supplements or undergoing niacin therapy should discuss alcohol use with their healthcare provider.

Nutrient Interactions

Niacin can affect the absorption and metabolism of other nutrients:

• Zinc: High-dose niacin may decrease zinc absorption.
• Chromium: Niacin may enhance chromium absorption.
• Vitamin B6: High doses of niacin may increase the body’s requirement for vitamin B6.

These interactions underscore the importance of a balanced approach to nutrition and the need for medical supervision when using high-dose niacin supplements or therapy.

Niacin in Special Populations: Considerations for Specific Groups

The benefits and risks of niacin can vary depending on individual circumstances and health status. How should niacin be approached in different populations?

Pregnant and Breastfeeding Women

Adequate niacin intake is important during pregnancy and lactation, but high-dose supplementation should be approached with caution:

• The RDA for niacin increases slightly during pregnancy and breastfeeding.
• High-dose niacin supplements are generally not recommended during pregnancy due to potential risks to fetal development.
• Breastfeeding women should consult with a healthcare provider before taking niacin supplements, as high doses can be passed to the infant through breast milk.

Older Adults

Older adults may have unique considerations when it comes to niacin:

• Age-related changes in metabolism can affect niacin absorption and utilization.
• Older adults are more likely to be taking medications that could interact with niacin.
• The potential cardiovascular benefits of niacin may be particularly relevant for this age group, but should be weighed against potential risks.

Individuals with Liver Disease

People with liver disease require special consideration when it comes to niacin:

• The liver plays a crucial role in niacin metabolism.
• High-dose niacin can potentially exacerbate liver damage in individuals with pre-existing liver conditions.
• Close monitoring of liver function is essential if niacin therapy is deemed necessary for these individuals.

Athletes and Fitness Enthusiasts

The role of niacin in energy metabolism makes it a nutrient of interest for those engaged in regular physical activity:

• Adequate niacin intake is important for optimal energy production during exercise.
• Some athletes may be tempted to use high-dose niacin supplements for potential performance benefits, but this practice is not supported by current evidence and may carry risks.
• Meeting niacin needs through a balanced diet is generally sufficient for most athletes.

These considerations highlight the importance of individualized approaches to niacin intake and supplementation, taking into account a person’s unique health status, lifestyle, and risk factors.

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.

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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.

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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.

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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

Such a famous “nicotine” and its nootropic effect – Nooteria Labs on vc.ru

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We tell you what vitamin B3 is, in what processes it is involved and how it affects the neuroplasticity of the brain.

Welcome to the Nooteria Labs blog! We are a manufacturer of complex supplements for an active life.

Nicotinic acid has been known for a long time and even for some time was considered an obsolete substance with an incomprehensible effect. Inexpensive ampoule “nicotine” in folk recipes was suggested to be rubbed into the scalp to improve hair growth. But the beneficial effects of the vitamin do not end there. Science does not stand still and the drug is experiencing a rebirth, more and more studies are being created on its effect on nerve cells under stress, the exchange of “bad” lipids and the functioning of the heart muscle. We understand with Nooteria Labs how and when nicotinic acid benefits.

Old new nicotine

Nicotinic acid (niacin, vitamin PP, vitamin B3) is a substance that takes part in many redox processes of the body, participating in the synthesis of enzymes, the metabolism of macro- and micronutrients. It is used as a medicine and as a dietary supplement.

The term “niacin” is used for nicotinic acid and its derivatives. Nicotinamide or niacinamide is the amide of niacin, known to chemists since 1867, when it was first isolated from the oxidation of nicotine. However, its metabolic role as a vitamin was investigated later, in the 1940s, and its nutritional significance even later.

The popular name “nicotine” has taken root only in Russian-speaking countries, as it forms a stable association with nicotine and smoking, which, of course, is not the case.

Niacin is one of the most stable water-soluble vitamins. It is rapidly absorbed in the upper part of the small intestine, enters the circulatory system and enters the cells, where it is included in the composition of coenzymes. Excess niacin is excreted in the urine. About ⅔ of the vitamin absorbed by the body is synthesized in the body from tryptophan.

How hunger and poverty helped to understand the importance of B3

Corn is a thousand-year basis of the diet of the population of the Mediterranean region and countries of South America. Favorite, diverse in cooking, unpretentious in breeding plant. In conditions of poverty and a shortage of protein foods, corn saved millions of people from starvation. However, it is the only mass-consumed crop with a critically low niacin content. For the Spanish peasants there was no rare disease, which they called mal de la rosa, the extreme degree of which was a triad of symptoms: diarrhea, dermatitis, dementia (progressive mental weakness), eventually leading to death. In 1771, Frapolli first described this pathology under the term “pellagra” (Italian pelle and agra – “rough skin”).

Pellagra was originally thought to be caused by toxins from poor-quality or spoiled corn. In 1917, scientists conducted experiments with a diet that included or excluded corn, and it was assumed that the cause of the disease was a lack of some nutrient. But what? In 1937, scientists were helped by veterinarians who treated dogs for a similar disease by fortifying the diet with proteins, and they noticed the similarity of symptoms. Nicotinic acid has been shown to be effective in both black tongue in dogs and pellagra in humans.

Now the enrichment of cereal crops with niacin and the availability of vitamin complexes have led to the virtual disappearance of pellagra in the population, with the exception of the poorest countries.

Where is niacin found? Spoiler: eat coarse grains with meat

Niacin is found in small amounts in most foods, but is abundant in whole wheat, rye, legumes, meat, poultry, and peanuts. Coffee lovers can sleep peacefully – coffee contains a large amount of niacin. However, we keep in mind that with the frequent use of alcohol, a deficiency of niacin is formed, at least partially.

Up to 90% of vitamin B3 is contained in the outer shell of the grain, so it is better to use coarse grains.

Some foods, such as milk, eggs, certain vegetables and fruits, are low in niacin but do not lead to B3 deficiency. Why is that?

Not all diets low in niacin lead to pellagra

This strange discrepancy was explained back in 1945 by a group of scientists from the Wisconsin Research Group. They found that not only niacin, but also tryptophan is effective in treating pellagra; later it was found that tryptophan is a precursor of niacin. Therefore, the human body is not completely dependent on dietary sources of B3, as it can be synthesized from tryptophan.

Interesting facts:

– 1 mg niacin will be synthesized from 60 mg of tryptophan.

– The efficiency of the tryptophan → niacin transition depends on nutrition and hormonal status. So, in the III trimester of pregnancy, this transition is 3 times faster than . The same speed of processes in women taking contraceptives. This is due to the fact that estrogens stimulate the work of tryptophan oxygenase.

– With a deficiency of vitamin B6 , the synthesis of niacin is also impaired.

An unfortunate coincidence: corn is poor not only in niacin, but also in tryptophan. In South America, this problem is solved by treating corn with lime water.

But other factors also influence the formation of a lack of niacin and tryptophan:

• Treatment with serious drugs for tuberculosis and leukemia;
• Excessive consumption of leucine, which inhibits the synthesis of niacin from tryptophan;
• Genetic pathologies such as Hartnap’s disease. This is a rare disease that masquerades as pellagra, but is based on a different mechanism – a genetic defect in the absorption and metabolism of tryptophan.

What processes does niacin involve

Nicotinic acid is a component of the coenzymes NAD (nicotinamide adenine dinucleotide) and NADP (nicotinamide adenine dinucleotide

phosphate).

Therefore, the function of niacin in the body is impressive:

• Participates in energy metabolism, that is, the processes of breakdown and synthesis of carbohydrates, fats and proteins. Organs with a high energy requirement (brain) or with a high turnover rate (gut, skin) are usually the most susceptible to coenzyme deficiencies;
• Increases the sensitivity of cells to insulin, influencing the glucose tolerance factor, therefore it can be used as a prevention of diabetes and its consequences;
• Reduces the level of “bad” fats in the blood plasma in large doses and prevents the formation of cholesterol plaques, that is, it has an antihyperlipidemic effect. It lowers the levels of all atherogenic lipoproteins, increases the level of protective lipoproteins more than any other drug. The positive and negative effects in combination with statins are studied in many studies. And more recently, the discovery of a specific nicotinic acid receptor was evidence that the drug stimulates the expression of the membrane cholesterol transporter ABCA-1. This looks promising for the long term use of this acid;
• Supports the stability of carbohydrate metabolism (glycogenolysis), including in the central nervous system;
• Slows down the aging of cells of the nervous system and demyelination of nerve fibers. Niacin-mediated macrophage/microglia rejuvenation enhances remyelination (repair of myelinated fibers) of the aging central nervous system;
• Dilates intracranial vessels and constricts extracranial vessels, affecting tension headaches and migraine;
• Restores mitochondrial energy metabolism, including in the brain, which is especially important in the development of oxidative stress.

Thus, in recent years, the neuroprotective and neurorestorative role of vitamin B3 in brain injury has been extensively studied in various in vitro and in vivo experiments.

Vitamin B3 dosage forms

Niacin is non-toxic. It is a pyridine derivative with a carboxyl group (COOH) in the 3rd position.

Another form of vitamin B3 is nicotinamide. It includes the corresponding amide, where the carboxyl group is replaced by a carboxamide group (CONH 2). There are also more complex amides and esters. Nicotinic acid and nicotinamide are mutually convertible compounds. But niacin has the ability to dilate blood vessels, while nicotinamide does not, nor does it affect cholesterol levels. Therefore, it is this form that is used in dietary supplements to correct the deficiency and potentiate the nootropic effect.

The human requirement for vitamin B3 is expressed in niacin equivalents: 1 equivalent is equal to 1 mg of nicotinic acid or 60 mg of L-tryptophan.

The requirement of a healthy person for niacin is 6.5 mg per 1000 kcal (4187 kJ) of energy expenditure or 15-25 mg per day. The amount of niacin formed in the human body is small, and most of it must come from food.

The average daily intake of niacin in different countries varies and ranges from 12-40 mg. In Russia, this is about 13-15 mg. At the same time is recommended from 20 mg per day in the presence of a deficiency of , and it occurs quite quickly: with heavy physical work, pregnancy and feeding, taking certain medications (for example, sulfanilamide drugs, antibiotics).

It is easy to calculate that if animal protein contains an average of 1.4% tryptophan, and vegetable protein about 1%, then with the intake of 60 g of protein per day with food, it will provide about 600 mg of tryptophan, which is equal to 10 mg of niacin. Therefore, in order to have an adequate level of tryptophan and niacin in the body, it is necessary to maintain an extremely healthy lifestyle with a rich and varied type of diet.

Side effects of niacin occur predominantly at high doses. As you know, the main principle of medicine is Primum non nocere, that is, “First of all, do no harm.” Do not harm yourself, do not take uncontrolled and isolated active substances. Use trusted sources, medicines or supplements that have verified ingredients and dosages.

B3 for brain function

We have already found out that the work of vitamin B3 in the central nervous system and its neuroprotective role has been sufficiently studied. It and its derivatives are recognized as key mediators of neuronal development and survival.

Niacin is a team player. With his friends, the B vitamins, he works more smoothly and efficiently.

If we are talking about increasing the activity and productivity of the brain, that is, a nootropic effect, then he prefers the command support of riboflavin, thiamine, magnesium ions, nicotinic acid, carnitine, coenzyme Q10, melatonin, lipoic acid, pyridoxine, folic acid and cobalamin. Supplements may well complement a normal healthy diet, which should be tailored to individual needs.

The Nooteria Labs line includes MindBooster , a multicomponent nootropic complex that includes vitamins B3, B5, B12, as well as adaptogens and caffeine. It has chosen a combination of substances and dosages so that they become the basis for proper metabolism and maintenance of brain function. MindBooster does not spur the body on, but provides additional resources in today’s active life.

When and who needs niacin as a supplement?

Rhythm of society, unhealthy diet, fad diets contribute to the development of vitamin B deficiencies. Niacin supplements are useful:

• Athletes – to increase endurance, but not exhausted after training; during competitions to show the best result;
• People with a high mental load, when there are many important decisions to be made, and the nervous system is at its limit;
• People intensively learning new skills, especially older people;
• For young mothers experiencing serious nervous and physical stress in conditions of exhaustion of the body after pregnancy

To summarize

Thus, nicotinamide affects many intracellular systems.