Drinking too much – on a single occasion or over time – can take a serious toll on your health.  Here’s how alcohol can affect your body:

Brain:
Alcohol interferes with the brain’s communication pathways, and can affect the way the brain looks and works. These disruptions can change mood and behavior, and make it harder to think clearly and move with coordination.  

Heart:
Drinking a lot over a long time or too much on a single occasion can damage the heart, causing problems including:

• Cardiomyopathy – Stretching and drooping of heart muscle
• Arrhythmias – Irregular heart beat
• Stroke
• High blood pressure  

Liver:
Heavy drinking takes a toll on the liver, and can lead to a variety of problems and liver inflammations including:

• Steatosis, or fatty liver
• Alcoholic hepatitis
• Fibrosis
• Cirrhosis

Pancreas:
Alcohol causes the pancreas to produce toxic substances that can eventually lead to pancreatitis, a dangerous inflammation in the pancreas that causes its swelling and pain (which may spread) and impairs its ability to make enzymes and hormones for proper digestion. 

Cancer:
According to the National Cancer Institute (NCI): "There is a strong scientific consensus that alcohol drinking can cause several types of cancer. In its Report on Carcinogens, the National Toxicology Program of the US Department of Health and Human Services lists consumption of alcoholic beverages as a known human carcinogen.

"The evidence indicates that the more alcohol a person drinks–particularly the more alcohol a person drinks regularly over time–the higher his or her risk of developing an alcohol-associated cancer. Even those who have no more than one drink per day and people who binge drink (those who consume 4 or more drinks for women and 5 or more drinks for men in one sitting) have a modestly increased risk of some cancers. Based on data from 2009, an estimated 3.5% of cancer deaths in the United States (about 19,500 deaths) were alcohol related."

Clear patterns have emerged between alcohol consumption and increased risks of certain types of cancer:

• Head and neck cancer, including oral cavity, pharynx, and larynx cancers.

• Esophageal cancer, particularly esophageal squamous cell carcinoma. In addition, people who inherit a deficiency in an enzyme that metabolizes alcohol have been found to have substantially increased risks of esophageal squamous cell carcinoma if they consume alcohol.

• Liver cancer.

• Breast cancer: Research has shown an important association between alcohol consumption and breast cancer—even one drink per day can increase a woman's risk for breast cancer by 5% to 15% compared to women who do not drink at all.

• Colorectal cancer.

For more information about alcohol and cancer, please visit the National Cancer Institute's webpage "Alcohol and Cancer Risk" (last accessed June 6, 2024).

Immune System:
Drinking too much can weaken your immune system, making your body a much easier target for disease.  Chronic drinkers are more liable to contract diseases like pneumonia and tuberculosis than people who do not drink too much.  Drinking a lot on a single occasion slows your body’s ability to ward off infections – even up to 24 hours after getting drunk.

For more information about alcohol's effects on the body, please visit the Interactive Body feature on NIAAA's College Drinking Prevention website.