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Over the past 20 to 30 years, a number of studies have indicated that drinking one or two glasses of wine or alcohol a day may decrease blood pressure and lead to fewer heart attacks and less heart disease. Scientists are still trying to determine if this is really true, or if people who drink moderately have lower blood pressure because they are healthier in other ways.

Positive Effects of Alcohol

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Alcohol may increase the levels of high-density lipoprotein (HDL) cholesterol in the blood. This is the so-called "good" cholesterol, and those with high levels of HDL cholesterol usually have less low-density lipoprotein (LDL), or "bad" cholesterol, in their blood. High levels of LDL can cause heart disease and high blood pressure. Regular exercise, consuming a healthy diet and taking vitamins and nutrients such as niacin can also raise the levels of HDL cholesterol and reduce blood pressure.

Negative Effects of Alcohol

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Researchers and doctors agree that more than one or two servings of alcohol a day for men and more than one a day for women can raise the level of fats called triglycerides in the blood and may lead to high blood pressure, heart failure, obesity, diabetes and stroke. A serving of alcohol is defined as one 12 oz. beer, 4 oz. of wine, 1.5 oz. of 80-proof spirits, or 1 oz. of 100-proof spirits. People who drink to excess may also suffer from cirrhosis, cancer, pancreatitis and cardiomyopathy, a condition in which the heart muscle is too weak to pump blood.

Is Red Wine Better for You?

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Some research has shown that red wine is better than other types of alcohol at preventing heart disease and high blood pressure. Chemicals in red wine, such as flavonoids and antioxidants, may help reduce blood pressure and LDL, although these are also found in foods such as grapes. People who drink one or two glasses of red wine a day may also be healthier because they eat more fruits and vegetables and exercise more.

What Do Doctors Recommend?

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The American Heart Association recommends that men do not drink more than two servings of alcohol a day, and women do not drink more than one. People who do not drink should not start, and people who have high blood pressure should use diet, exercise and medication, instead of alcohol, to lower their blood pressure. Anyone who wants to prevent high blood pressure should quit smoking, get plenty of exercise and eat right instead of drinking alcohol.

About the Author

Lisa Magloff

Since graduating with a degree in biology, Lisa Magloff has worked in many countries. Accordingly, she specializes in writing about science and travel and has written for publications as diverse as the "Snowmass Sun" and "Caterer Middle East." With numerous published books and newspaper and magazine articles to her credit, Magloff has an eclectic knowledge of everything from cooking to nuclear reactor maintenance.