Alcohol and the Brain — Short and Long-Term Impacts

— By Brian Mears, DNAP, APRN, CRNA, PMHNP

Understanding What Alcohol Really Does to Your Mind

We’re not here to judge. At Alleviant, we understand that ease of access, cultural norms, and emotional pain all influence our decisions — including whether or not we drink.

But while alcohol is widely accepted in our society, its effects on the brain are often underestimated — or misunderstood.

Our goal is simple: to educate you with clear, research-based facts so you can make informed, empowered decisions for your mental, emotional, and spiritual health.

What Happens to Your Brain When You Drink?

Alcohol is a central nervous system depressant — meaning it slows down brain activity. Its effects begin within minutes and vary depending on the amount consumed.

Short-Term Effects:

• Impaired decision-making and risk assessment (prefrontal cortex)

• Slowed reaction time and coordination (motor cortex, cerebellum)

• Disrupted memory formation (hippocampus)

• Emotional volatility and lowered inhibition (limbic system)

• Sedation and drowsiness (reticular activating system)

That’s why people under the influence may say or do things they later regret — alcohol impairs the very regions of the brain responsible for judgment, empathy, and self-control.

Blood Flow and Cerebral Vasculature

In the short term, alcohol causes vasodilation (widening) of blood vessels — but with long-term use, it leads to vasoconstriction and reduced cerebral blood flow.¹

Chronic alcohol use can:

• Decrease oxygen and nutrient delivery to brain tissue

• Contribute to white matter loss and brain shrinkage

• Increase the risk for stroke and cognitive decline

• Impair neurovascular coupling (the brain’s ability to regulate blood flow where it’s needed)

Brain Metabolism and Toxin Load

The liver metabolizes alcohol into acetaldehyde — a toxic compound that crosses the blood-brain barrier and damages neurons.²

Additionally:

• Alcohol disrupts glucose metabolism, the brain’s primary energy source

• Increases oxidative stress and inflammation

• Impairs mitochondrial function — the “powerhouses” of your cells

• Promotes neurodegeneration, especially with binge or chronic use³

Long-Term Brain Changes

Heavy or consistent alcohol use is linked to:

• Shrinkage of the frontal lobes — responsible for planning, logic, empathy, and impulse control

• Disruption of neurotransmitter balance, including dopamine, GABA, and glutamate

• Increased risk for depression, anxiety, and cognitive disorders

• Thiamine deficiency (Vitamin B1), leading to memory problems or Wernicke-Korsakoff Syndrome

Brain scans of chronic drinkers often show structural changes that correlate with mood instability, executive dysfunction, and memory loss.

Alcohol and Behavior

Alcohol is involved in:

• 40–50% of violent crimes⁴

• 30% of suicides⁵

• Up to 50% of fatal motor vehicle accidents⁶

Why? Because alcohol lowers inhibitions and increases impulsivity, especially in young adults whose prefrontal cortex is still developing.

Even occasional use can affect decision-making, sleep, and emotional regulation — especially in those already struggling with mental health conditions.

Final Thoughts: What You Choose Affects How You Think

Alcohol is legal and socially accepted — but that doesn’t make it harmless. It affects blood flow, energy metabolism, emotional control, and long-term brain health.

Again, our goal isn’t to judge — it’s to help you see clearly. The more you understand how substances interact with your brain, the more empowered you are to make decisions that align with your goals, values, and overall well-being.

Concerned about how alcohol might be affecting your mental clarity or emotional balance?

We’re here to help — with compassion, evidence, and real solutions.

References

1. Volkow, N. D., et al. (1997). Decreased brain metabolism in neurologically intact healthy alcoholics. American Journal of Psychiatry, 154(1), 101–107.

2. Lieber, C. S. (2000). Alcohol and the liver: 1994 update. Gastroenterology, 106(4), 1085–1105.

3. Harper, C. (2007). The neurotoxicity of alcohol. Human & Experimental Toxicology, 26(3), 251–257.

4. Bureau of Justice Statistics (2019). Alcohol and Crime: Data from Victims and Offenders.

5. Kaplan, M. S., et al. (2014). Alcohol use and suicide rates: A nationwide analysis. American Journal of Public Health, 104(11), 2103–2110.

6. National Highway Traffic Safety Administration (2022). Traffic Safety Facts: Alcohol-Impaired Driving.