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Reduced or Increased Risk of Blood Clots Due to Drinking

Drinking alcohol in moderation is legal for adults in the United States who are at least 21 years old. According to the National Institute on Alcohol Abuse and Alcoholism (NIAAA), almost 87 percent of people in the US, ages 18 and older, drank alcohol at least once in their lives. About 70 percent of adults drank at least one alcoholic beverage in the past year, and around 56 percent report that they drank in the past month.

While moderate drinking is a normal part of daily life for most people in the country, the Centers for Disease Control and Prevention (CDC) found that excessive drinking can cause severe health problems and leads to 88,000 deaths every year. A study published in the Journal of the American Medical Association (JAMA) found that in 2001-2002 and 2012-2013, the drinking habits of Americans changed radically for the worse: There was an 11 percent increase in drinking annually, nearly 30 percent increase in high-risk drinking, and close to a 50 percent increase in alcohol use disorder (AUD), commonly called alcoholism.

As Americans increasingly drink too much in the form of binge drinking, heavy drinking, or AUD, the risks of health problems increase. This is not just alcohol poisoning or drunk driving, but chronic health problems like heart disease. Although some medical studies have found that moderate drinking can provide some positive blood thinning effects, reducing the risk of blood clots, drinking too much has the opposite effect.

Alcohol Abuse and Blood Clots

The American Society of Hematology (ASH) defines a blood clot – also called blood coagulation or a thrombosis – as the gathering of proteins in the blood along with platelets to form a solid or semisolid mass in a blood vessel. Clots form naturally all the time to heal internal and external injuries. A scab that forms after you get a cut, for example, is a type of blood clot.

However, blood clots can become dangerous when they form in a blood vessel without any obvious injury and do not naturally dissolve. Depending on whether a clot forms in an artery or vein, it may cause slightly different problems.

Deep vein thrombosis is a type of clot that forms in a major vein in a leg, arm, pelvis, or other part of the body. These clots are dangerous because they can cause a buildup of blood, leading to swelling and preventing oxygen from circulating effectively around the heart. A piece of the clot may also break off and enter the heart or lungs where it becomes wedged and may cause a heart attack or pulmonary embolism.

For people with a family history of blood clots or heart disease, drinking a moderate amount of wine or beer, especially red wine, may confer some benefits because one serving of alcohol can slightly thin the blood. Drinking more than two servings of alcohol per day, however, increases the risk of blood clots because the number of platelets in the blood increases. Before self-prescribing alcohol to prevent heart problems or blood clots, it is important to understand what a serving of alcohol is. The CDC defines one serving as:

  • 12 ounces of beer, which is about one bottle
  • 5 ounces of wine, or a small glass
  • 1.5 ounces of hard alcohol, or a single shot glass

One of these servings of alcohol per day, with at least two days per week without alcohol consumption, may benefit heart health. However, there is no such thing as completely safe drinking, so if you have any concerns about heart health, it is better to avoid drinking. This is especially true for those who have a family history of heart disease or blood disorders, or who are on any kind of prescription medication, including blood thinners.

Ways That Alcohol Abuse Increases Risk of Blood Clots and Cardiovascular Damage

Drinking too much increases blood clotting problems through several mechanisms.

  • Liver damage: Alcohol is processed through the liver, and excessive drinking damages this organ. One of the problems associated with liver damage is the reduced ability to produce proteins that regulate blood clotting. This thins the blood in moderation, which may be beneficial for some people, but could be problematic for others. At higher levels, this heightens the risk of clotting, which increases the risk of damage from clots.
  • Platelets: Too much alcohol increases platelets in the blood, so they are more likely to clot randomly. Alcohol also activates platelets, meaning they are more likely to begin forming clots. Long-term, excessive drinking causes long-term, consistent platelet activation.
  • Weight gain: Alcohol has a lot of calories, and even among those who choose to drink too much rather than eat meals, there is an elevated risk of gaining body fat. Having more body fat means there are more lipids in the blood, which increases the risk of developing blood clots.
  • Sedentary lifestyle: People who sit for a long time, especially on planes, increase their risk of blood clots in general. Adding alcohol to 12-hour flight or a sedentary job adds to the risk of blood clots.
  • Gender differences: Drinking too much increases the risk of arterial fibrillation in both men and women, but it is a more significant increased risk for men. Arterial fibrillation is a condition in which the upper chambers of the heart, or the atria, twitch or spasm irregularly rather than rhythmically; this can trigger blood clots and lead to a stroke or heart attack. However, women who take hormonal birth control and drink excessively are also at a very high risk for blood clots. Hormonal birth control by itself increases clotting factors in the blood by 170 percent while decreasing anticoagulant factors by 20 percent.
  • Strokes: Drinking more than two servings of alcohol per day increases the risk of a stroke, which can be caused by a blood clot in the brain, by 50 percent. The risk of hemorrhagic strokes also increases. These strokes are not caused by blood clots, but by fewer platelets.
  • Deep vein thrombosis (DVT): Drinking more than three ounces of liquor per week – which is two shots of hard alcohol – increases the risk of DVT by 5 percent. However, the study that discovered this correlation did not further examine personal habits, and there may be a stronger correlation between binge drinking (four or five drinks in two hours) or AUD than just the amount of liquor consumed per week.

People who already suffer from blood clots should not drink alcohol at all, especially if your doctor has prescribed any blood-thinning medication. Mixing alcohol with any prescription drug is dangerous, and mixing alcohol with blood thinners decreases the effectiveness of this drug. If you have a prescription for a blood thinner like warfarin, the risk of uncontrolled bleeding increases with moderate drinking while the risk of blood clots increases with heavy or binge drinking.

The Red Wine Myth

A chemical found in red wine, called resveratrol, is associated with lower cholesterol levels, especially “bad cholesterol,” or high-density lipoprotein (HDL) cholesterol. While the mechanism behind this link is not well understood, publications immediately issued articles about the finding. Unfortunately, the popular press around wine’s potential benefits for heart health may have contributed to an increase in excessive drinking.

While the scientific research found that one serving of red wine, which is only five ounces, can benefit heart health, the study did not consider other harmful effects of wine, like more calories, risk of stomach damage, risk of liver damage, and increased sugars. Since many people do not know how much an appropriate serving is, the result for too many was dangerous consumption of alcohol, which did not incur any benefit to heart health and may have increased the risk of blood clots and other issues for many Americans.

Preventing Blood Clots by Overcoming Alcohol Abuse

The American Heart Association (AHA) does not recommend drinking alcohol because of its risk of heart damage, including increased risk of blood clots. While moderate drinking is less dangerous than excessive drinking, it is important to avoid drinking alcohol at all if you have concerns about your cardiovascular health or concerns about blood clots. You should also speak to your doctor about weight management, healthy eating, and exercise to change cholesterol, blood pressure, and heart health more effectively than you can with red wine or any other serving of alcohol.

If you drink too much or are concerned about how much you drink, you should speak to a physician about lowering your alcohol intake or getting treatment through a rehabilitation program. Working with an addiction specialist to safely detox from alcohol and then get behavioral treatment through rehab is the best process for ending AUD and other forms of problem drinking. Fortunately, there are many evidence-based programs available, which specialize in treating alcohol use disorder.

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