Heavy drinking can cause the number of oxygen-carrying red blood cells to be abnormally low. This condition, known as anemia, can trigger a host of symptoms, including fatigue, shortness of breath, and lightheadedness
2. Cancer
"Habitual drinking increases the risk of cancer," says Jurgen Rehm, PhD, chairman of the University of Toronto's department of addiction policy and a senior scientist at the Centre for Addiction and Mental Health, also in Toronto. Scientists believe the increased risk comes when the body converts alcohol into acetaldehyde, a potent carcinogen. Cancer sites linked to alcohol use include the mouth, pharynx (throat), larynx (voice box), esophagus, liver, breast, and colorectal region. Cancer risk rises even higher in heavy drinkers who also use tobacco.
3. Cardiovascular Disease
Heavy drinking, especially bingeing, makes platelets more likely to clump together into blood clots, which can lead to heart attack or stroke. In a landmark study published in 2005, Harvard researchers found that binge drinking doubled the risk of death among people who initially survived a heart attack.
Heavy drinking can also cause cardiomyopathy, a potentially deadly condition in which the heart muscle weakens and eventually fails, as well as the heart-rhythm abnormalities atrial and ventricular fibrillation. Atrial fibrillation, in which the heart's upper chambers (atria) twitch chaotically rather than constrict rhythmically, can cause blood clots that can trigger a stroke. Ventricular fibrillation causes chaotic twitching in the heart's main pumping chambers (ventricles). It causes rapid loss of consciousness and, in the absence of immediate treatment, sudden death.
4. Cirrhosis
Alcohol is toxic to liver cells, and many heavy drinkers develop cirrhosis, a sometimes-lethal condition in which the liver is so heavily scarred that it is unable to function. But it's hard to predict which drinkers will develop cirrhosis. For some unknown reason, women seem to be especially vulnerable.
5. Dementia
As people age, their brains shrink, on average, at a rate of about 1.9% per decade. That's considered normal. But heavy drinking speeds the shrinkage of certain key regions in the brain, resulting in memory loss and other symptoms of dementia.
Heavy drinking can also lead to subtle but potentially debilitating deficits in the ability to plan, make judgments, solve problems, and other aspects of "executive function," which are "the higher-order abilities that allow us to maximize our function as human beings," says James C. Garbutt, MD, professor of psychiatry at the University of North Carolina at Chapel Hill School of Medicine.
In addition to the "nonspecific" dementia that stems from brain atrophy, heavy drinking can cause nutritional deficiencies so severe that they trigger other forms of dementia.
6. Depression
It's long been known that heavy drinking often goes hand in hand with depression, but there has been debate about which came first -- the drinking or the depression. One theory is that depressed people turned to alcohol in an attempt to "self-medicate" to ease their emotional pain. But in 2010, a large study from New Zealand showed that it was probably the other way around -- that is, heavy drinking led to depression.
7. Seizures
Heavy drinking can be a cause of epilepsy and can trigger seizures even in people who don't have epilepsy. It can also interfere with the action of the medications used to treat the disorder.
8. Gout
A painful condition, gout is caused by the formation of uric-acid crystals in the joints. Although some cases are largely hereditary, alcohol and other dietary factors seem to play a role. Alcohol also seems to aggravate existing cases of gout.
9. High Blood Pressure
Alcohol can disrupt the sympathetic nervous system, which, among other things, controls the constriction and dilation of blood vessels in response to stress, temperature, exertion, etc. Heavy drinking -- and bingeing, in particular -- can cause blood pressure to rise. Over time, this effect can become chronic. High blood pressure can lead to many other health problems, including kidney disease, heart disease, and stroke.
10. Infectious Diseases
Heavy drinking suppresses the immune system, providing a toehold for infections, including tuberculosis, pneumonia, HIV/AIDS, and other sexually transmitted diseases (including some that cause infertility). People who drink heavily also are more likely to engage in risky sex. "Heavy drinking is associated with a threefold increase in the risk of contracting a sexually transmitted disease," Rehm says.
11. Nerve Damage
Heavy drinking can cause a form of nerve damage known as alcoholic neuropathy, which can produce a painful pins-and-needles feeling in the extremities, as well as muscle weakness, incontinence, constipation, erectile dysfunction, and other problems. Alcoholic neuropathy may arise because alcohol is toxic to nerve cells or because nutritional deficiencies attributable to heavy drinking compromise nerve function.
12. Pancreatitis
In addition to causing stomach irritation (gastritis), drinking can inflame the pancreas. Chronic pancreatitis interferes with the digestive process, causing abdominal pain and persistent diarrhea. Some cases of chronic pancreatitis are triggered by gallstones, but up to 60% stem from alcohol consumption.
