Does Alcohol Kill Brain Cells?

Does Alcohol Kill Brain Cells?

There are several ways alcohol can impact brain cells, including nutritional deficiency, acetaldehyde neurotoxicity, and inflammation. While occasional drinking is unlikely to kill brain cells, heavy drinking and binge drinking can damage cells, inflame surrounding tissue, and lead to functional impairments.

Alcohol’s Impact on Cognitive Function & Memory

Alcohol affects several brain areas, but in particular, it can interfere with the prefrontal cortex, which is the brain’s command center. The prefrontal cortex receives information from numerous brain areas, like the limbic system, which is involved in memory, learning, and emotion. Alcohol interferes with memory function and emotion, which also impacts the performance of your command center.

Such changes can be seen transiently with intoxication, but they can become more persistent and severe with heavy or chronic alcohol use. Eventually, heavy alcohol use can lead to irreversible damage, as is seen in wet brain syndrome.

Factors Influencing Alcohol’s Impact on the Brain

The impact of alcohol will vary depending on several factors, including weight, age, metabolism, health conditions, and frequency of use. Some individuals have particularly low levels of the enzyme that breaks down alcohol’s byproduct, acetaldehyde, which increases its toxicity. Additionally, older individuals (60 to 69 years) and women are generally more susceptible to alcohol’s toxic effects.²

How Frequency of Alcohol Use Impacts the Brain

The frequency at which an individual drinks directly impacts the likelihood of brain damage. Individuals classified as heavy and binge drinkers are at greater risk. Drinking classifications vary across organizations (e.g., NIAAA, SAMHSA, CDC), but they have similar parameters for what is considered light, moderate, and heavy drinking.^{6, 7}

Drinking is usually classified as:

• Infrequent drinking: Consuming less than 12 drinks in the past year.
• Light drinking: Consuming less than 4 drinks per week, but at least 12 drinks in the past year, on average.
• Moderate drinking: Consuming no more than 1 drink per day for women or 2 drinks per day for men.
• Heavy drinking: Consuming 8 or more drinks per week for women and 15 or more drinks per week for men.
• Binge drinking: Consuming alcohol at a rate fast enough to raise one’s blood alcohol concentration (BAC) to .08% or higher. Usually, this equates to around 4-5 drinks in 2 hours for the average adult.⁷

One drink can be 12 ounces of a 5% ABV beer, 8 ounces of 7% ABV malt liquor, 5 ounces of 12% ABV wine, or 1.5 ounces of 40% ABV (80-proof) liquor like vodka, whiskey or rum.⁵

Short-Term Effects of Alcohol

Alcohol (ethanol) is a sedative and mild anesthetic that produces several short-term effects, which are amplified with increasing dosage. Cognitive functions (e.g., alertness, concentration, and decision-making) decline with alcohol consumption. Perhaps the biggest danger is that self-perception is also impacted; one may feel sharper, smarter, and more capable when drinking, leading to a decision to drive or engage in other activities that could result in injury or death.

Behaviorally, alcohol reduces one’s inhibitory capacity, thus leading drinkers to be more impulsive. Emotionally, alcohol similarly releases control of certain emotions, like anger or sadness, potentially leading to aggressive or depressive behavior. Sometimes, alcohol is used to numb uncomfortable emotions. Excessive or binge drinking has more severe short-term effects, like cardiovascular, respiratory, and neurological changes, with the extreme being alcohol poisoning, seizure, coma, and death.

Short-term effects of alcohol include:

• Feeling relaxed
• Slower reflexes
• Slower cognition
• Slurred speech
• Clumsiness
• Imbalance
• Decreased alertness
• Reduced concentration
• Increased impulsivity
• Inhibition
• Mood changes (e.g., happy, sad, angry)
• Reduced anxiety
• Energy changes (more in the first hour, less thereafter)
• Sleepiness or fatigue
• Increased need to urinate
• Drop in body temperature
• Gastrointestinal symptoms (e.g., nausea)
• Facial flushing

Long-Term Effects of Alcohol Misuse

An occasional drink is unlikely to have long-lasting effects on the brain when consumed responsibly; however, chronic drinking can have longer-lasting effects. There have been suggestions that low to moderate consumption has cardiovascular benefits, although recently, others have purported that even light to moderate drinking (1-6 drinks per week) can lead to brain cell loss and holds no protective effect over abstinence.^{3, 8, 9, 10}

Even if one consumes alcohol in moderation, tolerance will build, and gradually larger amounts will be required to achieve the same effect or buzz. This slippery slope can cause chemical and physical changes to brain cells over time that can lead to chronic problems with decision-making, learning, memory, and motivation for engaging in healthy daily activities. In adults, the brain ages faster with chronic (daily) alcohol consumption than with occasional drinking or abstinence.²⁴

Long-term effects of alcohol include:

Brain Atrophy

Deterioration of the brain, or brain atrophy, occurs in a few different ways. With ongoing, heavy alcohol use, there are changes in white matter (i.e., the part of a neuron along which the electrical signal is sent)¹¹ and loss of gray matter (receiving part of the neuron).^{12, 13} As the gray matter deteriorates, the ventricles (cavities containing cerebrospinal fluid) enlarge, and the sulci – the space between the gyri (worm-like folds on the brain surface) – widen.^{14, 3}

These structural changes to the brain result in poor communication between brain regions (e.g., prefrontal, insular, and cingulate cortex, striatum) and impairments to pathways involved in reward processing, impulse control, and emotional regulation. Some individuals may have impairments in these functions that predispose them to alcohol misuse or dependence.

Thiamine Deficiency

Chronic alcohol use can lead to several nutritional deficiencies, including thiamine, magnesium, calcium, iron, and electrolytes.¹⁵ Thiamine, or Vitamin B1, in particular, is crucial for proper nerve function. The human body can’t produce it, and so we need to get thiamine through diet. Alcohol can cause a thiamine deficiency and resulting nerve damage (neurotoxicity) in a few ways.

First, alcohol can lead to vomiting or diarrhea, which reduces the absorption of thiamine from any food eaten prior. Second, alcohol reduces the enzyme thiamine pyrophosphokinase, which is needed to break down thiamine. Lastly, alcohol damages the gastrointestinal wall, reducing the amount of thiamine that gets absorbed.³

Chronic thiamine deficiency reduces essential enzymes and mitochondrial function that are necessary for healthy cell function. Without thiamine, brain cells are damaged and eventually die. So, yes, alcohol can cause brain cells to die. As groups of brain cells deteriorate, Wernicke’s Encephalopathy and Korsakoff’s Syndrome can ensue.

Wernicke-Korsakoff Syndrome

Wernicke-Korsakoff Syndrome refers to two closely related neurological conditions – Wernicke’s encephalopathy and Korsakoff syndrome –  that result from thiamine deficiency. While alcohol is often the cause of thiamine deficiency, other conditions can lead to this malnutrition, too (e.g., eating disorders, cancer, AIDS, chronic infection).

Wernicke’s Encephalopathy is the acute form of this syndrome, characterized by confusion, motor impairments (e.g., balance, coordination), and involuntary eye movements. In many cases, it is reversible with proper treatment. However, when left untreated (an estimated 80% of cases remain undiagnosed)¹⁶, it can lead to further brain damage and Korsakoff Syndrome.

Korsakoff syndrome (also called Korsakoff psychosis or alcohol-induced persisting amnestic disorder) is a mostly irreversible neurological condition characterized by severe memory impairment (akin to that seen in Alzheimer’s Disease), confusion, imbalance, and other vital processes (cardiovascular, body temperature regulation). At the point where Korsakoff syndrome is diagnosed, permanent brain damage has occurred. Only about 25% of individuals with Korsakoff syndrome are able to stop the progression with abstinence from alcohol and maintain remaining function.¹⁷

Neuroinflammation

Just as inflammation of the leg can prevent smooth walking, inflammation in the brain can interfere with normal function. Alcohol can lead to inflammation of the brain (neuroinflammation) in several ways.

First, ethanol can irritate the gut (e.g., stomach and intestines), leading to an inflammatory response that extends across the blood-brain barrier, affecting the brain as well.¹⁸ Alcohol can also be inflammatory by increasing the neurotransmitter glutamate and corticotropin-releasing hormone, resulting in potential damage to brain cells. Lastly, alcohol can cause the microglia (maintenance cells that protect against pathogens and clean injured or dying cells) to overreact, leading to further neuroinflammation.³

Acetaldehyde Neurotoxicity

When you ingest alcohol, it is converted to acetaldehyde, a toxic byproduct that causes many of alcohol’s side effects, like dry mouth, nausea, headache, and facial flushing. It also damages DNA and triggers an immune response that leads to further cell damage in the body and brain and increases the risk of cancer.¹⁹

Functional impairments can arise when damage accumulates to brain cells over time. While one brain cell won’t significantly affect function, damage to groups of neurons or inflammation of surrounding tissue can. Such impairments may include problems with memory and concentration, confusion, emotional lability, and behavioral changes, to name a few.

Neurogenesis Issues

Neurogenesis refers to the creation of new neurons in the brain that occur even in adulthood. The hippocampus is a brain area involved in learning and memory, and it’s normally graced with new neurons throughout life. Alcohol consumption impedes this process of neurogenesis and the learning and memory functions that depend on it.

Neurochemical Dysfunction

Normal daily functioning depends on effective communication between neurons and different areas of the brain. Neurotransmitters are the chemicals transmitted between neurons that carry the message across each synapse (the space between neurons). Alcohol affects several neurotransmitter systems, including GABA, dopamine, endocannabinoids, and glutamate, among others.

Changes to these neurotransmitter levels lead to reduced activity in prefrontal brain areas that are normally involved in executive functions like decision-making, inhibition, and problem-solving. With these functions compromised, one is more likely to behave impulsively and make poor decisions. Other affected regions include limbic areas (e.g., hippocampus, amygdala) that are involved in memory and emotion, and the cerebellum and midbrain areas involved in balance and coordination.

Reward Processing Deficits

The reward circuit of the brain incorporates areas involved in decision-making and inhibitory control (prefrontal cortex), emotion (amygdala, hippocampus), and anticipation (striatum). People who have an impaired reward circuit are at greater risk for addiction to alcohol or other addictive substances or behaviors (e.g., gambling). However, consuming alcohol further disrupts the brain’s reward circuitry, leading to increased craving for the addictive substance and blunted desire for other beneficial, rewarding things.²⁰

Impulse Control Problems

Impulsivity is the tendency to respond to a feeling (e.g., craving, desire, anger), thought, or stimulus (e.g., an alcoholic beverage) quickly without considering the negative consequences of each response. Alcohol and impulse control dysfunction have a bi-directional relationship: alcohol decreases the brain’s ability to control impulses, and people with impulse control problems are more likely to drink.⁴ Subsequently, people are more likely to engage in risky behaviors under the influence of alcohol.

Inhibition difficulties, together with reduced ability to make sound decisions, can lead both to increased alcohol consumption as well as to risky behaviors that can cause harm or death to oneself or others. This is why you should never count on yourself to be the evaluator of whether you can drive after drinking and why you should make other arrangements before you take your first sip of alcohol.

Emotional Dysregulation

Some people may use alcohol to cope with their feelings of distress or anxiety. While light to moderate drinking can transiently reduce anxiety, heavy drinking can actually increase anxiety and impair one’s ability to process emotion.

Those with alcohol use disorder tend to have difficulty perceiving the emotions of others and of themselves (referred to as alexithymia). Alexithymia can interfere with social relationships, and while this difficulty may predate alcohol use, it may also result from heavy alcohol use and worsen with it. As alcohol dependence develops, so does the tendency to misperceive anger in faces that are actually expressing disgust or sadness.^{21, 22}

Sleep Disturbance

Alcohol and sleep are reciprocally tied, as alcohol is often used as an aid for sleep and relaxation, yet in moderate amounts, alcohol can actually disrupt sleep and exacerbate several medical conditions, including sleep disorders like insomnia and sleep apnea. With moderate to high use, alcohol interferes with normal sleep patterns and may induce a vicious cycle of unhealthy habits (e.g., excess daily caffeine use alternating with nightly sedatives) that increases both alcohol consumption and sleep disturbances.

Alcohol can have a substantial impact on one’s quality and quantity of sleep, affecting the time it takes to fall and stay asleep. It affects daily functioning, with alertness and cognition being most impacted. Consumption of alcohol, even up to 6 hours before bed (“happy hour drinking”), can interfere with the natural sleep cycle, with excessive doses and frequent use having the most substantial effects on sleep, daytime functioning, and overall physical and mental health.

Non-Neurological Medical Consequences

Long-term alcohol use can lead to cardiovascular conditions, like high blood pressure, heart disease, and stroke, as well as digestive conditions, like liver disease and gastrointestinal dysfunction. Damage to the gastrointestinal lining and chronic exposure to alcohol’s toxic byproduct, acetaldehyde, can also increase the risk for various forms of cancer. Alcohol also reduces nutritional absorption and weakens the immune system, increasing the likelihood that you will get sick.²³

How Alcohol Exposure in Utero Impacts the Brain

Alcohol consumed by expectant mothers does pass through to the fetus. Prenatal exposure to alcohol can result in a host of fetal alcohol spectrum disorders (FASD), characterized by a range of mild to severe structural abnormalities (e.g., growth retardation, brain malformation, craniofacial dysmorphism) and functional impairments (e.g., cognitive and behavioral disorders).^{25, 3}

Common signs and symptoms of FASDs include:

• Learning disabilities
• Concentration difficulty
• Speech and language delay
• Hyperactivity
• Impulsivity
• Social difficulty
• Behavioral problems
• Vision problems
• Hearing impairment
• Poor coordination
• Low body weight
• Shorter than average height
• Heart condition
• Kidney problems
• Orthopedic problems

How Alcohol Exposure as a Minor Impacts the Brain

Typically, neural development during the teen years is characterized by a reduction of gray matter as the brain prunes superfluous neural connections.  At the same time, white matter (i.e., the myelin sheathing around each neuron’s axons or extensions) expands as the brain strengthens its remaining connections (the “keepers”). However, when adolescents engage in consistently heavy drinking during this critical developmental period, there is a larger-than-normal pruning of gray matter and less-than-expected white matter growth (i.e., the connections that the brain maintains into adulthood are not as well protected).

Some teens with a family history of alcohol use disorder, or who tend to be more impulsive, may be more prone to underage drinking, and early intervention during this critical period is particularly important.

How to Reduce the Risks of Alcohol Killing Brain Cells

Abstinence is the best way to avoid the dangers of alcohol, but if one is going to drink, there are practices to reduce the risk of brain damage. First, moderation is key; avoid binge drinking. Set an intention for yourself before you start drinking, focus on mindful drinking, and ask a sober friend not to let you exceed a certain number of drinks.

Try to keep consumption to once or twice a week at most. This gives your body and brain a chance to recover and reduces the buildup of tolerance to the desired effects of alcohol. Drink a full glass of water after each alcoholic beverage, and try not to drink on an empty stomach. Eat food (carbohydrates are particularly good) prior to your first drink.

Some people are at greater risk for alcohol use disorder (e.g., family history, genetic predisposition, trauma, or other mental health disorders), and any exposure to alcohol can cue the vicious cycle of addiction. Abstinence and lifestyle change (to avoid cues that would trigger craving and use) is the only way to stay sober and healthy. Unfortunately, addiction is a lifelong disease, and most people (70%) moving through addiction recovery will have relapses.²⁶ However, the longer a person stays sober, the lower the risk for relapse.

Treatment for Problematic Alcohol Use

Problematic alcohol use doesn’t start overnight; it develops gradually and often goes unnoticed until it starts interfering with one’s relationships and job (or schoolwork). While one may notice changes in oneself, it is usually a loved one who notices and intervenes to get help. There are many resources available to help with alcohol use disorder. However, the hardest part is getting the individual to acknowledge the problem and be open to receiving help.

Treatment options for problematic alcohol use include:

• Cognitive behavioral therapy (CBT): CBT for substance use helps the individual identify maladaptive thought patterns and behaviors associated with addiction, develop healthy skills and coping strategies to challenge maladaptive thinking, and manage cravings. Over time, these new ways of thinking and behaving are reinforced, with the goal being long-term change and relapse prevention.
• Psychodynamic therapy: Psychodynamic therapy is less common than CBT for alcohol misuse but it can be helpful in cases of unresolved trauma and unconscious anxieties that give rise to alcohol use disorder.
• Dialectical behavior therapy (DBT): DBT is similar to CBT but with more focus on emotional regulation, mindfulness, and interpersonal skills to manage emotional distress. A DBT therapist will help an individual struggling with addiction to accept current circumstances while also actively working towards change.
• Motivational interviewing: Motivational interviewing for substance use helps the individual to see recovery from alcohol misuse as occurring in steps or stages. The therapist helps the individual discover their own intrinsic desire for change and establish clear, realistic steps for change through guided but open-ended questioning and reflective listening.
• Contingency management: Contingency management involves reinforcing positive behaviors like abstinence, treatment attendance, and medication adherence with “agreed on, immediate, tangible rewards.”²⁷ It is particularly effective for individuals with a dual diagnosis of schizophrenia and alcohol use disorder. Elements of contingency management may be combined with other therapeutic approaches like CBT.
• Family therapy: Understanding and adjusting family dynamics can be a very powerful tool in treating alcohol use disorder. As alcohol use disorder often involves the whole family, and not just the person struggling, a family therapist will help the family members improve communication, support each other, and find healthy ways to cope with challenges during alcohol withdrawal, recovery as well as instances of relapse.
• Group therapy and support groups: Support groups like Alcoholics Anonymous (AA) play a crucial role in the recovery process for many individuals and their families. AA or other group therapy interventions provide a safe, non-judgmental space where individuals can connect with others experiencing similar struggles with addiction and dependence. Being surrounded by others at various recovery stages can be immensely beneficial as it offers a sense of understanding and hope, a preview of what may be ahead, a perspective on what lies behind, and a feeling one is not alone in one’s journey.
• Psychedelic-assisted therapy: Therapeutic psychedelics, like psilocybin therapy and ketamine therapy, have recently surged in popularity as a treatment option in clinical research trials for several conditions, including alcohol use disorder.²⁸ When combined with psychotherapy, two psilocybin treatment sessions resulted in reduced craving and alcohol consumption (27-41% fewer days) extending through 32 weeks.^{29, 30} Ketamine treatment improved the abstinence rate from 24% to 66% after one year of abstinence.³¹

When to Seek Professional Support

If you or someone you care about is drinking alcohol in excess, it can be beneficial to get help before a vicious cycle of alcohol misuse strengthens. Treatment will vary depending on the severity of alcohol dependence and the presence of complicating factors. For severe cases, an inpatient treatment setting may be necessary to stabilize the person and help them through detoxification and withdrawal. For less severe cases, an outpatient treatment clinic may be sufficient to support the individual through the treatment process.

If you’re noticing that alcohol is getting in the way of relationships, work, or other aspects of daily life but are not sure how to proceed, you may want to find a therapist or psychiatrist who can help determine the best approach to treatment. If you have trouble finding a local therapist, consider searching an online therapist directory or online therapy platform.

How to Help Someone Who Is Misusing Alcohol

It can be overwhelming to determine how to help someone who is using alcohol excessively. The hardest part is helping the individual acknowledge that there is a problem. There are several strategies that can help, such as not keeping alcohol in the home or going to psychotherapy together.