Researchers analyzed data from 3865 adults and found that more than 50 percent said that they did not know that alcohol increases cancer risk (Cancer Epidemiology, Biomarkers & Prevention, Dec 1, 2022). The people who incorrectly thought that alcohol doesn’t cause cancer were the ones most likely also to think incorrectly that alcohol can help to prevent heart attacks. Another study, of 4,513,746 insured adults in Korea, found that reduced alcohol consumption was associated with reduced cancer incidence and increased alcohol consumption was associated with increased cancer incidence (JAMA Netw Open, Aug 24, 2022;5(8):e2228544).
Alcohol intake has been linked with increased heart rate, high blood pressure, weakened heart muscle and irregular heartbeats (Alcohol Clin Exp Res, Dec 2015;39(12):2334–2344), all of which can increase the risk of heart attacks and strokes. Recent data show that 65 percent of North Americans support adding warning labels and drinking guidelines on the dangers of alcohol, but only 34.4 percent support banning outdoor alcohol advertising (American Journal of Preventive Medicine, Feb 1, 2022;62(2):174-182).
Some Studies on Wine Helping to Prevent Heart Attacks Were Flawed
A review of 45 studies found that the studies that associated moderate drinking with reduced heart attack rates could all be flawed (Journal of Studies on Alcohol and Drugs, May 2017;78(3):375-386). Studies designed to show that alcohol prevents heart attacks must have a control group of nondrinkers, but many members of the control groups were former drinkers who had given up alcohol because they were alcoholics, were diabetic, had heart, liver or kidney diseases, or had some other disease or condition that forced them to give up alcohol. When these unhealthy people are removed from the non-drinking control groups, the corrected studies show that even moderate drinking can shorten your life. Alcohol causes inflammation and oxidative stress that damages cells and increases risk for disease. There may be a threshold at which alcohol causes disease, but alcohol at any dose increases cancer risk and does not help to prevent heart attacks.
Reducing Alcohol Intake to Reduce Cancer Risk
Alcohol is associated with increased risk of cancers of the breast, liver, colon, rectum, mouth, pharynx, larynx, and esophagus (Lancet Oncology, 2006;7(2):149–156). A review of many studies found that alcohol increases tumor growth, tumor spread, immune response, and death (Alcohol Res, 2015; 37(2):311–322). A report from Sweden found that regular drinkers who stopped drinking reduced their risk for liver cancer by more than six percent for every year they went without alcohol, and that it would take 23 years for a former drinker’s risk for liver cancer to equal that of a person who was never a drinker (BMC Cancer, Oct 13, 2011;11:446). The authors also studied esophageal cancers, of which more than 50 percent in men are caused by alcohol. After five years of not drinking, the risk for esophageal cancer dropped by almost 15 percent, but it took 35 years of abstinence to reduce their chances of developing esophageal cancer to the level of non-drinkers (Addiction, Jul 2012;107(7):1234-43).
How Alcohol Can Cause Cancer
Occasional exposure to alcohol has not been shown to cause cancers. However, repeated exposure to alcohol causes repeated damage to cells to markedly increase risk for several types of cancers. If your cells lived forever, they would overgrow and destroy other tissues. Normal cells are not supposed to live forever. The DNA in all cells in your body cause apoptosis in which cells self-destruct after a certain number of doublings. For example, red blood cells live up to 120 days and then die. Skin cells live only 28 days and then die. When you drink alcohol, the alcohol circulates from your intestines into your bloodstream to cells throughout your body, where it can damage DNA so the cells no longer self-destruct (apoptosis). Cells that do not die can overgrow and spread, which is the definition of cancer (Nature, Jan 3, 2018;553:171–177).
How Alcohol Can Cause Heart Attacks
As soon as alcohol comes in contact with a cell, it can cause damage. Your immune system tries to repair that cell damage by producing cells and chemicals to cause healing. These cells and chemicals are exactly the same as those that kill germs when they try to enter the cells in your body. As soon as your damaged tissue heals, your immune system is supposed to dampen down. However, if you drink regularly, you continue to damage the cells in your body and your immune system stays active all the time. This is called inflammation, and these cells and chemicals that are supposed to kill germs can start to attack your own cells. They can punch holes in your arteries to start plaques to form, and they can dislodge the plaques to cause bleeding and then clotting that completely obstruct heart arteries to cause a heart attack.
Many people have the mistaken belief that it is safe for women to take up to one drink per day and for men to take up to two drinks per day. Almost 30 percent of North Americans drink more than that. Studies of alcohol consumption have never shown that any amount of alcohol is “safe” or beneficial. Whatever you decide about your own consumption of alcohol, do not base your decision on bad information from the alcoholic beverage industry. Occasional drinking probably will not harm you, but repeated drinking increases your risk for many different cancers, heart attacks and strokes.