Niacin is another name for vitamin B3, and HDL stands for high density lipoprotein. In the blood, a molecule known as LDL, or low density lipoprotein, carries cholesterol from the liver, where it is made, to body cells. If there is more cholesterol than the cells require, it can build up inside arteries, increasing the chance of a stroke or heart attack. HDL takes cholesterol away from the cells and returns it to the liver and, for this reason, cholesterol bound to HDL is sometimes referred to as good cholesterol, because it is associated with a decreased health risk. The connection between niacin and HDL arises from the fact that taking niacin supplements has been shown to raise HDL levels and lower LDL, making it less likely that heart attacks and strokes will occur.
A person's risk of developing disease of the heart and arteries is raised if she has high levels of cholesterol bound to LDL, sometimes known as bad cholesterol, in the blood. The risk is also greater if a person has levels of HDL which are too low. For this reason, treatment to prevent heart and artery disease usually consists of measures to boost the level of HDL as well as trying to reduce LDL.
At first, methods which do not involve medication may be tried in order to correct cholesterol levels. These include eating a healthy, low-fat diet, taking regular exercise, stopping smoking and losing weight. If these steps are not enough, then a number of drugs are available which lower cholesterol in different ways, some by reducing its production in the liver, others by preventing it from being absorbed in the intestine. Research concerning niacin and HDL has shown that, in high doses, niacin can raise HDL levels more than other treatments, increasing them by up to 35 percent.
In order to benefit from this relationship between niacin and HDL, high doses of niacin are required, much greater than those found in ordinary multivitamin pills. Sources of niacin such as meat, fish, eggs, cereals and dairy products are also unlikely to provide the levels needed. For niacin and HDL to interact effectively, high dose niacin pills should be taken under a doctor's supervision, as part of an overall treatment plan to regulate cholesterol.
Different types of niacin tablets are available, some acting more quickly than others, and there are a number of possible side effects. These include headaches, dizziness, raised blood sugar levels, stomach upsets, liver problems and facial flushing. A doctor will be able to advise on the best type of tablet and dose required to gain the beneficial effects associated with niacin and HDL while minimizing side effects.