Vitamin B3
What is it? Overview Usage Side Effects and Warnings

What is Vitamin B3?

Vitamin B 3 is required for the proper function of more than 50 enzymes. Without it, your body would not be able to release energy or make fats from carbohydrates. Vitamin B 3 is also used to make sex hormones and other important chemical signal molecules.

Vitamin B 3 comes in two principal forms: niacin (nicotinic acid) and niacinamide (nicotinamide). When taken in low doses for nutritional purposes, these two forms of the vitamin are essentially identical. However, each has its own particular effects when taken in high doses. Additionally, a special form of niacin called inositol hexaniacinate has shown some promise as a treatment with special properties of its own.

There is no question that niacin (but not niacinamide) can significantly improve cholesterol profile, reducing levels of total and LDL ("bad") cholesterol and raising HDL ("good") cholesterol. 1 2 3 4 5 6 7 However, unpleasant flushing reactions as well as a risk of liver inflammation and dangerous interactions with other cholesterol-lowering drugs have kept niacin from being widely used (see Safety Issues ).

Niacinamide may improve blood sugar control in both children and adults who already have diabetes. 8 In addition, some evidence had suggested that regular use of niacinamide (but not niacin) might help preventdiabetes in children at special risk of developing it; 9 unfortunately, subsequent studies indicate that it probably does not work. 10...

Safety Issues

When taken at a dosage of more than 100 mg daily, niacin frequently causes annoying skin flushing, especially in the face, as well as stomach distress, itching, and headache.65 In studies, as many as 43% of individuals taking niacin quit because of unpleasant side effects.44

A more dangerous effect of niacin is liver inflammation. Although some reports suggest that it occurs most commonly with slow-release niacin, it can occur with any type of niacin when taken at a daily dose of more than 500 mg (usually 3 g or more). Regular blood tests to evaluate liver function are, therefore, mandatory when using high-dose niacin (or niacinamide or inositol hexaniacinate). This reaction almost always goes away when niacin is stopped. Note: Contrary to claims on some...