Using Niacin to Reduce Cholesterol

The B vitamin niacin, also called nicotinic acid, is an essential part of a healthy diet. But at very high daily doses—1,500–4,500 mg—crystalline nicotinic acid acts as a drug instead of a vitamin. It can reduce total cholesterol levels up to 25 percent, lowering LDL and raising HDL, and can rapidly lower the blood level of triglycerides.

It does so by cutting the liver’s production of very low-density lipoprotein, which is ordinarily converted into LDL. Because niacin has been around since the 1950s, it is well studied. You might be wondering why niacin isn’t on top of the cholesterol- lowering hill, instead of statins.

There are two main reasons: its side effects and confusion over the different types of niacin out there. The original niacin preparations used for lowering cholesterol were pure crystalline nicotinic acid, which enters the bloodstream quickly. Appropriately, it is called fast-acting or immediate-release niacin.

The quick spike in niacin triggers a “niacin flush” in almost everyone who isn’t used to this drug. This uncomfortable feeling of heat, itching, tingling, or redness in the skin starts within a few minutes of taking niacin and subsides within an hour or so.

Less common side effects are gastrointestinal upset (such as queasiness, heartburn, or gas) and dizziness or light-headedness, especially when rising from bed or a chair. To minimize flushing and other side effects, several companies have developed extended-release formulations of niacin.

Like timed-release cold capsules, these deliver a steady stream of niacin over several hours. By avoiding a surge in nicotinic acid in the bloodstream, these lessen—but don’t eliminate—flushing. There’s a downside, though.

Because blood levels of niacin stay high all day long, the liver never gets a break from processing niacin, as it does with immediate-release niacin that quickly leaves the body. This can overwhelm the liver and has led to numerous cases of liver problems, including liver failure requiring a transplant.

An intermediate-release form that’s available only by prescription seems to offer the best of both worlds. This drug, sold as Niaspan, delivers niacin slower than the original fast-acting types but faster than the extended-release versions.

This, and the fact that it’s taken once a day at bedtime, helps minimize flushing, or at least the experience of it. Because it is washed out of the body in a few hours, it is easier on the liver than extended-release niacin. Several brands of “no-flush” niacin are also on the market.

In theory, one of its components, inositol hexanicotinate, is absorbed into the bloodstream, and its niacin components are gradually released. In reality, it barely elevates niacin levels in the blood and barely changes cholesterol levels. If you have chronic liver disease or certain other conditions, including diabetes, gout, and peptic ulcer, be sure to mention them to your doctor.

Niacin might exacerbate them. Everyone on niacin should have their liver function checked occasionally, especially after starting on niacin or changing your dose. People with diabetes should monitor their blood sugar even more carefully when they’re on niacin. Here are some other tips for taking niacins:

  • Choosing a niacin. If you have patience, it’s worth trying immediate-release niacin, especially if you have to pay for your medications yourself. Otherwise, Niaspan is a good, though expensive, alternative. I don’t recommend no-flush niacin because it doesn’t elevate niacin levels in the blood enough to have an effect on cholesterol.
  • Start slowly. When beginning immediate-release niacin therapy, take 100 mg right after dinner for a week. The next week, take 100 mg after breakfast and dinner. The following week add 100 mg after lunch. Each week after that, double the dose at one meal until you reach your daily target.
  • Aspirin helps. If you can take a full-strength or even lowdose aspirin, or already do, take it each day about thirty minutes before your first dose of niacin. This can dramatically reduce the niacin flush.
  • Eat up. Taking niacin with or soon after a meal helps prevent digestive irritation. If you plan on having something spicy, take your niacin later, with a less fiery snack.
  • Don’t make changes before talking to your doctor. A switch from immediate-release niacin to extendedrelease, or vice versa, requires changing the daily dose. Merely changing types can lead to hepatitis or liver failure. Don’t increase your dose or take any kind of high-dose niacin, even those sold over the counter, without talking to your doctor.
  • Stop taking the drug if you have the flu or other illness that can tax the liver. Once you are well, start up again at a lower dose than you had been taking.