What Is Vitamin B3?

Inositol hexaniacinate (IHN) is a molecule made up of one inositol and six niacin (vitamin B-3) molecules. Inositol is a hexagonal ring structure, and in the IHN molecule, one niacin is chemically bound to each point of the hexagon. It is often sold as "flush-free" or "no-flush" niacin in commercial supplements, and it is a useful supplement for those who cannot tolerate the flush response caused by plain niacin.

Health Benefits of Vitamin B-3

Much like plain niacin, IHN can act to supplement niacin levels in the body. This means that it can impact metabolism and offer benefits to the nervous system and mental health. It was initially believed that IHN provided all of the benefits of niacin supplementation without the flushing side effects. Recent research has shown that this is not necessarily the case, with supplemental IHN showing 0% free nicotinic acid (niacin) present.

Vitamin B-3 Effects On Metabolism

Niacin is involved in several metabolic processes in the body, and it also plays a role in the production of stomach acid and bile, which facilitates the initial digestion of food. Niacin affects blood sugar by acting as a component of the glucose tolerance factor, one of the blood-sugar regulatory molecules in the body. In this way, it is said to act as a potential therapeutic supplement for diabetes. It also helps with the digestion of fats, carbohydrates, and protein because niacin is converted to NADH in the body. NADH increases the rate of chemical reactions in the body and helps to repair damaged DNA.

Nervous System and Mental Health

Niacin is an important vitamin for the proper functioning of the nervous system and has been well researched for its ability to improve the outcomes of mental illness, such as schizophrenia. It has also been used to help treat depression and anxiety.

Vitamin B-3 Niacin Deficiency

Niacin deficiency is known as "pellagra", which often appears with symptoms of diarrhea, dementia, dermatitis, and eventually results in death ("the 4 D's"). It can also cause a swollen tongue, an enlarged heart, and extreme sensitivity to sunlight.

IHN Vs Niacin

Interestingly, recent research has shown that IHN does not have the same cardiovascular health benefits that can be attributed to niacin alone. Several research trials have demonstrated no change to HDL cholesterol levels in those people supplementing with IHN. The lack of a "flush" response further reduces the benefit to the cardiovascular system and also prevents the anti-histamine effects that plain niacin can produce when supplemented.

How Should I Take IHN?

In general, it is always a good idea to take B vitamins in a B complex, as they all work together in the body. Often, IHN is found alone under the label "no-flush niacin", or in combination formulas for lipid or cholesterol regulation based on old research that hadn't yet established its inability to alter cholesterol levels. 

If you are looking to alter your cholesterol levels, it would be a better idea to supplement with plain niacin as its beneficial effects are established in research. Supplemental IHN can also be found in B complex formulas as a non-flushing alternative for health benefits such as improved mental health and increased metabolism. It is useful for supplementation in individuals who cannot tolerate the flush response of regular niacin. 

The dosage recommendations for niacin vary widely depending on the application. Daily supplementation for general health is usually suggested at between 100 and 500mg of IHN per day. 

When attempting to achieve cardiovascular benefits, most studies use between 1,000 and 4,000mg per day, although the results in this area are not promising. It is important to note that higher dosages can be associated with toxicity. Because of this, it is recommended that people taking higher doses of niacin to modify their cholesterol levels should be monitored by their physician using blood tests to monitor liver function.

Niacin Toxicity

Immediate toxicity of niacin appears as nausea, dizziness, itching, vomiting, and dermatological conditions such as extreme flushing and rashes. It is important to note that high doses of niacin have also been associated with indigestion, high blood sugar, heart arrhythmias, and even liver damage. It is a good idea to be monitored by your healthcare practitioner while taking higher doses of niacin regularly.

Important Information

The elderly and those with impaired digestion are particularly prone to deficiency of B vitamins in general, so it is often a good idea to supplement with a B complex in these individuals. Even though IHN is marketed as non-flush niacin, it may still cause a small amount of harmless flushing. Despite previous belief, current research has not found benefit for IHN as a treatment for high cholesterol and dyslipidemia. Use regular niacin instead for these conditions. Time-release forms of B3 may increase the risk of liver toxicity. Do not crush or break tablets. Caution should be used when supplementing IHN if you have a stomach ulcer, active bleeding, or liver or kidney disease. Vitamin B3 should not be used by pregnant or nursing mothers as it may cause harm to the baby. Vitamin B3 can interact with: blood thinners, blood pressure, and heart medications, sleeping pills, estrogen, alcohol and sulfonamide antibiotics.