Alcohol remains America’s favorite drug. According to the 2019 National Survey on Drug Use and Health (NSDUH), 85.6% of people ages 18 and older reported drinking alcohol at some point in their lifetime, 69.5% reported drinking in the past year, and 54.9% reported drinking in the past month. The same study also showed an emerging trend of High-Intensity Drinking among adults.
Recently, consumption has been on the rise. Emerging evidence reveals a notable increase in alcohol consumption since the COVID-19 pandemic. Additionally, studies have shown an increase of alcohol consumption in colder months, especially in colder regions. As winter approaches, now is a good time to review the effects of alcohol on the brain and body.
Effects on the Brain
Alcohol affects the brain in several ways. Specifically, it represses an excitatory neurotransmitter, glutamate, and increases an inhibitory neurotransmitter, GABA. As a result, one’s thoughts, movements, and speech become impaired—increasingly so with further consumption. Alcohol’s repressive effect as a nervous system depressant means that it slows certain brain functions: thought, perception, attention, judgment, memory, sleep and coordination.
Alcohol also increases the release of the neurotransmitter dopamine, which plays a key role in the brain’s “reward system”. As one drinks, the alcohol signals to the brain that it’s having a good time, so one may continue drinking to chase the release of dopamine. With consistent exposure, however, the effects of dopamine begin to diminish. At this point, one is often attached to the effects of dopamine so they continue to drink with the hopes of feeling the “high”, despite not receiving it.
Alcohol can disrupt the brain’s communication channels, affecting its functions and even its shape. Alcohol interferes with the brain areas that control balance, memory, language, and judgment, increasing your chances of injury and other adverse effects. Prolonged heavy drinking causes neuronal changes such as a reduction in the size of brain cells.
The developing brain is particularly susceptible to alcohol. Alcohol abuse during adolescence and early adulthood can alter brain development and lead to long-lasting changes in brain structure and function.
Beyond a general understanding of how alcohol interacts with the brain, let’s take a more detailed look at some of the common effects of alcohol on the brain, both short and long-term.
A serious consequence of alcohol abuse is commonly known as “blackouts.” Blackouts are memory gaps for events occurring while intoxicated. These gaps occur when one drinks enough alcohol to temporarily block the transfer of memories from short-term to long-term memory (known as memory consolidation) in a region of the brain called the hippocampus.
Continuing to drink alcohol despite clear signs of serious disability can lead to excessive alcohol consumption, and possibly overdose.
Also known as “alcohol poisoning,” alcohol overdose occurs when there is an excess of alcohol in the bloodstream, and areas of the brain that control basic life-support functions such as breathing, heart rate, and temperature regulation begin to shut down.
Symptoms of alcohol overdose include confusion, difficulty maintaining consciousness, vomiting, seizures, difficulty breathing, slowed heart rate, clammy skin, lack of gag reflex, other sluggish reactions, and even extreme hypothermia. Overdose of alcohol can cause permanent brain damage or death.
While the effects of alcohol on memory remain the subject of much research, we know that drinking may have significant and lasting effects on the brain, ranging from “slips” in memory to permanent and debilitating conditions requiring life-long care. Even moderate drinking may leads to short–term impairment, as shown by extensive research on the impact of drinking on driving. Excessive use in older ages increases the risks of developing Alzheimer’s, and, coupled with malnourishment, can cause Wernicke–Korsakoff syndrome, which can cause more permanent brain damage, including dementia and amnesia.
A number of factors influence how and to what extent alcohol affects the brain, including:
Volume, frequency of use
Starting age, number of years use
Current age, gender, genetic background
General health condition
Many people with alcohol dependence also suffer from mental illness. Mental illness may increase the risk of developing alcohol dependence, just as alcohol dependence may increase the risk of developing a mental illness. While some may drink as a result of their mental illness, others may develop mental illness as a result of their alcohol dependence. Mental illness and alcohol dependence may be considered co-occurring conditions, which have a tendency to aggravate each other. When one issue is ignored, the other often worsens.
Some of these impairments may be detected after only a few drinks, and quickly resolve when drinking stops. However, a person who drinks heavily over a long period of time may have brain deficits that persist well after he or she achieves sobriety.
Effects on the Body
Typically, the body reacts to alcohol as a waste product, and so immediately works to excrete it. Even small amounts of alcohol can have an effect on the body’s systems. The following is a more detailed, but not comprehensive list of the effects of alcohol on the body, provided by the National Institute of Alcohol Abuse and Alcoholism.
Excessive drinking can weaken your immune system, making your body more vulnerable to disease. Dangerous infections, including pneumonia and tuberculosis, are more common among chronic drinkers.
Alcohol may inhibit new bone production, putting one at risk of osteoporosis and bone fractures. Additionally, alcohol makes muscles more likely to cramp and/or atrophy.
In women, alcohol may cause a cease of menstruation and infertility. It also heightens the risk of breast cancer.
One common side effect of alcohol abuse in men is erectile dysfunction. Male hormone production also may be inhibited, sometimes causing infertility.
Alcohol-related heart problems may include muscle-cell poisoning, irregular heartbeat, high blood pressure, stroke, and even heart attack.
Alcohol makes it difficult for our intestines to control bacteria and absorb nutrients that can lead to malnutrition. Alcohol is also known to cause:
Salivary gland damage
Gum disease & tooth decay
Acid reflux & heartburn
Stomach ulcers & gastritis
Excessive alcohol consumption can cause the pancreas to lose normal insulin production and create toxic substances that can lead to its destruction. An abundance of alcohol can harm the liver, which can lead to hepatitis, jaundice, and cirrhosis. Alcohol may cause kidney, bladder, and prostate inflammation.
According to the National Cancer Institute: "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 the consumption of alcoholic beverages as a known human carcinogen.
Research reveals clear correlating patterns between alcohol consumption and increased risks of certain types of cancer, including:
Head and neck cancer, (including oral cavity, pharynx, and larynx cancers)
Esophageal cancer (particularly esophageal squamous cell carcinoma)
Drinking in Moderation
Many of the long-term effects of alcohol may be avoided by practicing moderation. Current guidelines from the Centers for Disease Control and Prevention (CDC) define moderate drinking as:
1 or fewer drinks each day for women
2 or fewer drinks each day for men
While past guidance around alcohol use generally suggests that a daily drink poses little risk of negative health effects and might even offer a few health benefits, more recent research suggests there’s really no “safe” amount of alcohol, as even moderate drinking can negatively impact brain and body health.