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How Alcohol Impacts the Brain

Alcohol and the Brain

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What Alcohol Means for Your Health

Do you indulge in a glass of wine every now and then? You are not alone. Over 86 percent of people ages 18 or older have reported drinking alcohol at some point in their lives. While occasional drinking is not likely to cause problems, moderate or heavy drinking can impact the brain, and alcohol can cause deficits over time if abused.

Alcohol in Your Body

Once ingested, alcohol affects your body quickly. It is absorbed through the lining of your stomach into your bloodstream, which then diffuses it into biological tissues throughout your body. Alcohol reaches your brain in only five minutes, with immediate effects appearing within 10 minutes.

After 20 minutes, your liver begins processing the alcohol. On average, the liver can metabolize 1 ounce of alcohol every hour. A blood alcohol level of 0.08, the legal limit for drinking, takes around five and a half hours to leave your system. Alcohol will remain in your urine for up to 80 hours and in your hair follicles for up to three months.

Your Brain on Alcohol

While alcohol is absorbed throughout your entire body, it particularly takes its toll on the brain. Alcohol interferes with the brain’s communication pathways, and can affect how your brain processes information.

There are several stages of alcohol consumption.

  • Euphoria. During the beginning stages of drinking, alcohol increases the release of dopamine, which creates a pleasurable sensation. During euphoria, you will feel relaxed but also experience minor impairment of reasoning and memory.
  • Depression, disorientation and memory loss. Once the blood alcohol level reaches beyond 0.05 blood alcohol content (BAC), blood and body tissue begin to absorb the extra alcohol, and euphoria turns to depression.
  • Excitement. At this stage, with a BAC from roughly 0.09 to 0.25, you are now legally intoxicated. The occipital lobe, temporal lobe and frontal lobe are all responsible for some of the deficits you experience at this level of alcohol consumption, including blurred vision, slurred speech and hearing, and lack of control, respectively. The parietal lobe, which processes sensory information, is also affected, causing loss of fine motor skills and a slower reaction time.
  • Confusion. A BAC of 0.18 to 0.3 typically manifests itself as disorientation. Your cerebellum, which helps with coordination, is impacted. As a result, you may need help walking or standing. Blackouts, or the temporary loss of consciousness or memory, are also likely to occur at this stage of consumption. This is a result of the hippocampus, the region of the brain that is responsible for making new memories, functioning improperly.
  • Stupor. If you reach a BAC of 0.25 to 0.40, you may experience some concerning symptoms that suggest alcohol poisoning has occurred. At this time, all mental, physical and sensory functions are severely impaired. The risk for asphyxiation or injury is high.
  • Coma. At a BAC of 0.35, you have the potential for going into a coma as a result of compromised respiration and circulation, motor responses and reflexes.
  • Death. A BAC over 0.45 may result in death due to alcohol poisoning or a failure of the brain to control all of the body’s vital physical functions.

Drinking and Driving

The impaired judgment you experience when drinking alcohol may cause you to think that you are still able to drive, regardless of your BAC. Drivers with a BAC of .08 are 11 times more likely to be killed in a single-vehicle crash than non-drinking drivers. Some states have enacted increased penalties for those driving with high blood alcohol content (.15 to .20 BAC or above) due to the increased risk of fatal accidents.

How Much Is Too Much?

Your body’s response to alcohol depends on a variety of factors, including age, gender, overall health, how much you drink, how long you have been drinking and how often you normally drink.

Occasional drinkers will typically recover once sobriety is reached. However, while their judgment is impaired, they may make poor decisions with lasting effects, such as driving under the influence.

Moderate drinkers, or those who consume one or two drinks per day, can have increased risks for breast cancer. They may also be prone to increased violence or accidents.

Heavy or chronic drinking is categorized as drinking heavily over an extended period of time. For women, this is classified as more than three drinks on any day or seven per week. For men, it’s more than four drinks per day or 14 per week. For perspective, a bottle of wine consists of five drinks.

Alcohol Abuse and Its Lasting Effects

Consistent abuse of alcohol can leave lasting damage. Over time, excessive drinking can lead to mental health problems, such as depression and anxiety. Alcohol abuse can lead to increased risk for certain types of cancers as well as severe brain damage. Alcohol abuse can lead to Wernicke-Korsakoff syndrome (WKS), which is characterized by amnesia, extreme confusion and visual disturbances. WKS is a brain disorder caused by a thiamine deficiency, or lack of vitamin B-1. A regimen of vitamins and magnesium, along with abstinence from alcohol, may improve symptoms.

Damage from drinking alcohol can result from the direct impact of alcohol on the body’s tissues as well as the indirect stress it puts on your body. Fortunately, most cognitive impairment can be reversed or improved within a year of abstinence.

If you or someone you know needs help, please consult your physician or contact Alcoholics Anonymous.

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