What is High-density lipoprotein and how does Niacin relate to it?
There is a great deal of interest in tinkering with high-density lipoprotein (HDL) cholesterol levels. HDL is the "good" cholesterol particle that sops up excess cholesterol from the atherosclerotic plaque in arteries and disposes of it in the liver. Persons with higher HDL levels have lower rates of heart disease, and that seems to be true even after low-density lipoprotein (LDL) levels are lowered by statins. The current guidelines say most of us should be aiming for a level of 60 mg/dL or more for HDL. An HDL level below 40 mg/dL is considered a risk factor for heart attack or stroke.
Niacin, a B vitamin (also known as vitamin B3), has long been used to increase high-density lipoprotein (HDL) cholesterol — the "good" cholesterol that helps remove low-density lipoprotein (LDL), the "bad" cholesterol from our bloodstream. Niacin (nicotinic acid) is a B vitamin that's used by our body to turn food into energy. Niacin also helps keep our nervous system, digestive system and skin healthy.
When it is used as a treatment to increase our HDL cholesterol or correct a vitamin deficiency, niacin is sold in higher doses usually prescribed by the doctor. High-dose niacin can cause stomach upset and make the skin flush or itch. Side effects are a problem when niacin is taken in such large doses. Niacin can increase blood sugar levels and lead to liver damage. Doctors usually advise people who have had gout to stay away from the pharmacological doses because they can increase uric acid levels.
But the most common side effect is flushing, a sensation of prickly heat in the skin that usually affects the head, face, and neck. People also turn red, and a few get itchy and suffer nausea. Flushing occurs because niacin in large amounts causes the release of prostaglandins that open blood vessels in and near the skin. Flushing tends to ease up after people have been taking niacin awhile, but flushing is uncomfortable and one of the main reasons people stop taking niacin.
More importantly, niacin can increase the risk of high blood sugar levels or type 2 diabetes, infection, liver damage and bleeding.
In the past, it was thought that HDL levels would increase even more if niacin was added to cholesterol medications called statins, such as atorvastatin (Lipitor) and simvastatin (Zocor). But recent studies indicate that niacin provides little additional benefit when compared with statins alone, and may increase the risks of serious side effects.
Most doctors no longer recommend niacin for first-line cholesterol control — except for people who can't tolerate statins. In those people, the benefits of niacin may outweigh the risk of potentially serious side effects.
Fatty fish and lifestyle changes
The omega-3 fats in fatty fish provide major benefits to heart health, including a reduction in inflammation and better functioning of the cells that line your arteries. There’s some research showing that eating fatty fish or taking fish oil may also help raise low levels of HDL cholesterol. In a study of 33 heart disease patients, participants that consumed fatty fish four times per week experienced an increase in HDL cholesterol levels. The particle size of their HDL also increased. In another study, overweight men who consumed herring five days a week for six weeks had a 5% increase in HDL cholesterol, compared with their levels after eating lean pork and chicken five days a week.
However, there are a few studies that found no increase in HDL cholesterol in response to increased fish or omega-3 supplement intake.
In addition to herring, other types of fatty fish that may help raise HDL cholesterol include salmon, sardines, mackerel and anchovies.
Eating fatty fish several times per week may help increase HDL cholesterol levels and provide other benefits to heart health.
Lifestyle changes are helpful in boosting HDL:
• Stop smoking if you're a smoker.
• Eat a healthy diet.
• Start an exercise program, with your doctor's permission.
Activities like brisk walking boost HDL levels, but aerobic exercise — the kind that really increases your heart rate — seems to have the added bonus of encouraging HDL's anti-inflammatory activity, even if the levels don't go up much. Losing weight, whether it be from diet or exercise, increases HDL. Smokers have lower HDL levels than nonsmokers. Levels bounce back up once people quit.
