Antioxidant Helps People with Low HDL Cholesterol
Doctors often talk about ways to raise people's high-density lipoprotein (HDL) cholesterol levels, because this "good" cholesterol is associated with a reduced risk of cardiovascular disease. Unfortunately, the advice frequently includes taking statin drugs. Now researchers have discovered an antioxidant that helps people who have low HDL cholesterol.
This antioxidant can benefit the heart
The beneficial antioxidant researchers at the University of Minnesota Medical School (UMMS) and the School of Public Health have discovered is actually an enzyme called glutathione peroxidase, or GPx3. This enzyme has several critical roles in the body, including the synthesis and repair of DNA, metabolism of cancer-causing substances, prevention of fat oxidation, and enhancement of the immune system.
In the study, the investigators evaluated three major risk factors for cardiovascular disease: smoking, high cholesterol, and high blood pressure. They examined 130 stored samples from individuals who had participated in the Minnesota Heart Survey and died of cardiovascular disease after 5 to 12 years of follow-up and compared them with 240 control samples.
The investigators found that GPx3 did not make a significant difference in people who had high levels of HDL cholesterol, but among those with low HDL, having high amounts of GPx3 had real potential.
In fact, "we found that people with high levels of the GPx3 enzyme and low levels of good cholesterol were six times less likely to develop cardiovascular disease than people with low levels of both," according to Jordon L. Holtzman, MD, PhD, the study's lead author and professor of pharmacology and medicine at UMMS.
Natural ways to improve HDL cholesterol
Besides statins and other drugs that are prescribed to help improve HDL levels, there are natural lifestyle changes you can make to improve good cholesterol. They include
- Achieve and maintain a healthy weight. Losing excess weight may reduce your HDL levels
- Exercise more. If you are more physically active, you can better achieve a healthy weight and improve your HDL. A recent study from Texas A&M University reported that exercise training in overweight and obese adults results in improvement in HDL and other lipid levels.
- Quit smoking. If you stop smoking, you may raise your HDL cholesterol by up to 10 percent.
- Select healthy fats. Foods that contain monounsaturated and polyunsaturated fats can improve the ability of HDL cholesterol to fight inflammation while unhealthy fats (e.g., trans fat, saturated fat) raise LDL cholesterol and damage blood vessels
- Imbibe in moderation. Studies show that moderate intake (1 drink for women, 2 drinks for men per day) can raise HDL cholesterol.
- Astaxanthin. At least one study suggests the antioxidant astaxanthin, which is derived from algae, may improve HDL cholesterol levels.
The authors point out that an estimated 50 million people in the United States have low HDL and low GPx3, a combination that can result in strokes and lethal heart attacks. The results of this latest study suggest GPx3 is an important enzyme to keep an eye on for this population.
Holtzman and his co-authors hope that with more research, taking a measure of GPx3 will be part of the routine blood test for identifying people at risk for cardiovascular disease. Soon there may be a way to help people with low HDL cholesterol through use of an antioxidant.
Buijsse B et al. Low serum glutathione peroxidase activity is associated with increased cardiovascular mortality in individuals with low HDLc. PLoS ONE 2012; 7(6): E38901
Greene NP et al. Acute exercise and training alter blood lipid and lipoprotein profiles differently in overweight and obese men and women. Obesity (Silver Spring) 2012 Mar 16
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