Niacin is amongst the medications used to lower the levels of cholesterol in the blood, and is well-known by doctors and patients who use it for the uncomfortable side effects niacin can cause.
There is some controversy over an alternative form of this drug, known as ‘flush-free’ niacin and what it can do for your cholesterol, and this article will discuss this in detail.
Niacin is also known as vitamin B3.
Niacin is a chemical that the body needs in the diet, although it can make a little for itself from an amino acid called tryptophan.
The body uses niacin to help get energy out of food, and in the processes that turn carbohydrates into fat.
But I don’t want to turn carbohydrates into fat, you might think. And there’s a lot of pressure in the media to avoid getting fat, but that’s not quite what I mean here - your body needs to be able to store carbohydrates as an energy source for later use, even in a slim individual, and it needs vitamin B3 to be able to do that efficiently.
Niacin is an important part of the pathway used to help the body break carbohydrates down in the first place, and it’s also part of the pathway in the liver that breaks down alcohol, so it’s got an important part to play in your diet.
It has been discovered that, due to these effects niacin has on the way your body gets and stores energy from food, that niacin can be used to boost energy levels and that niacin helps to lower the levels of cholesterol in the blood.
Niacin does the first action by the effect it has on the chemical pathways your body uses to break up carbohydrates - niacin acts as a co-enzyme, working alongside the body’s enzymes to enhance their action.
Niacin reduces cholesterol by helping break down some of the proteins that the body uses to carry fats in the bloodstream, low-density lipoproteins (LDLs) and triglycerides.
Because fat isn’t soluble in water, the body uses these LDLs and triglycerides to act as carrying agents.
Fat binds or sticks to them, and they are soluble in water and can carry the fat with them when they enter the blood.
Cholesterol is one kind of fat that is carried this way. If you break down the LDLs and triglycerides, there are less around for the body to carry fat in the blood with, so the total amount of fats in the bloodstream is reduced.
Niacin also acts as a vasodilator, a drug that makes blood vessels wider and promotes a larger blood supply to parts of the body. And niacin reduces levels of free radicals, which are a by-product of various chemical processes that can produce damage to cell tissues and DNA, so niacin is a very useful vitamin to have around, and is used in the treatment of quite a wide range of symptoms.
As well as niacin's use in decreasing blood cholesterol, niacin's been used to treat blood sugar levels in hypoglycaemia, improve fatigue, help the body handle stress, problems of teeth and gums, the treatment of acne, alcoholism, several mental illnesses including schizophrenia, and to improve your sex drive. Quite the wonder drug!
But that’s also a measure of how important vitamins are in your diet - they have a huge effect on all kinds of processes in the body.
The disease Pellagra is caused by a lack of niacin, and the symptoms of that include skin lesions, bowel disruption and eventual dementia, which also underlines how much you need your vitamins.
You can buy vitamin supplements containing B vitamins over the counter in many pharmacies, health food stores and even supermarkets. But in a normal diet, you only need to take about 20 milligrams a day, and your body is very capable of extracting that from a balanced diet.
You can get a good source of niacin from several common foods, including white meats like chicken, tuna, brown rice, peanuts, broccoli and figs, although the body can (as I said above) make its own if you aren’t eating any. But if you’re also short on some of the other B vitamins, B1, 2 and 6, then you can’t make your own either.
For the cholesterol-lowering effects, though, you need much higher doses of niacin, and these are prescribed drugs that you should get through your doctor.
If you are taking more than 1g of niacin in a day, it should be under medical supervision - vitamins are generally very good for you, but you can have too much of a good thing, so always check the amounts you are taking against the recommended daily allowance (RDA).
They are nicotinic acid (or just niacin), nicotinamide and inositol hexaniacinate (which is the chemist’s way of describing a chemical composed of one molecule with six niacin molecules stuck to it). This last one is also referred to as ‘flush-free’ niacin.
Of these three forms, niacinamide is the form in which the drug is active as a co-enzyme; the other two have to be broken down into niacinamide before they can be used by the body.
Nicotinic acid is the only form that helps reduces cholesterol.
In the UK, it isn’t used as a first line treatment, and is usually reserved until drugs like statins haven’t worked.
This is mostly because of the side effects related to the high doses of niacin you need to take.
Niacin is an important part of the diet, and can be used to improve your general health in all kinds of ways. But it does have side effects, like any active chemical that you take.
Chief amongst these is that you have to take niacin in quite a high dose before it works to reduce cholesterol, and that when taken in these doses, it produces a skin flush.
Remember that I mentioned it is a vasodilator? That means it acts on blood vessels, causing them to widen and transport more blood.
Niacin does this by making cells in the skin release a chemical called histamine. If you have allergies, you may know a bit about histamine - it’s the chemical that anti-histamines (the kind you take to control hayfever) work against, and it causes hot, itchy flushes in the skin.
That's exactly the same kind of effect that a big dose of niacin produces, and although some people find it rather invigorating and harmless (especially as it only lasts for ten to twenty minutes) many people dislike it enough to stop taking their niacin.
Niacin can also cause headaches and stomach aches, and, in large enough doses over a long period of time, has been shown to cause changes in liver structure.
Niacin may also make gout, diabetes, certain heart palpitations and stomach ulcers worse, so you should avoid its use if you suffer from any of these.
Inositol hexaniacinate, this drug where six molecules of niacin are stuck to a molecule of inositol, is quite a big, bulky molecule.
It’s expensive to manufacture, but because the body has to break the six niacin pieces away before it can use them, it takes a while before it becomes active in the body.
The theory is that due to this slow release, you end up getting the same dose of niacin but without the big rush that causes the histamine release and the flushes - hence ‘flush-free nicacin’. Which sounds ideal, as you’d be getting all the benefits of taking niacin without the unpleasant side effects.
Unfortunately, there is mounting evidence to show that although you don’t get the side effects, you don’t really get the cholesterol reduction either.
This is because the flush-free niacin gets broken down to nicotinamide, and that doesn’t have the effect on cholesterol than nicotinic acid does.
As some brands of inositol pills are available as over-the-counter vitamin supplements, and as these brands are much more expensive than the other kinds of niacin pills, there is real concern that some patients will end up paying far more than they need to for something that doesn’t actually lower their cholesterol.
Inostitol is used in the treatment of certain diseases like Raynaud’s disease - it still helps with energy levels and is a vasodilator. It is certainly a useful drug in its place and is unlikely to cause any ill effects. But it doesn’t help reduce cholesterol like the other forms of niacin do, so you should avoid using it if that’s the result you are trying to achieve.
In a sense, you are doing yourself harm if you are taking it to reduce cholesterol - it’s a waste of time and money that you could spend on something beneficial.
If you are interested in managing your cholesterol levels, you are probably already well aware of the importance of a well-managed diet.
Vitamin B3, aka niacin, will have an important place in that diet, or in the diet of anyone who wants to stay healthy.
Niacin is a naturally occurring chemical that the body needs to maintain good health. It can also be used as a drug, helping to reduce your cholesterol.
But drugs should be treated with respect. Unfortunately there are plenty of companies who will be happy to sell you expensive drug supplements - niacin comes in several forms that don’t act in the same ways or have the same effects. Be sure you understand what you are taking and why!
Remember, flush-free niacin (or inositol hexaniacinate) does not reduce cholesterol in the body.
Main write by Dr. James D. Hogg, (BSc Oxon, MBBS & BA Hons), medical doctor, and minor rewrite by D S Urquhart.