Alcohol, while enjoyable in moderation for some adults, is ultimately a toxin. When ethanol enters your system, it takes quite a journey through your organs and tissues before leaving your body. Let’s trace alcohol’s path to understand exactly how it affects the brain, liver, stomach, muscles and more so you can make informed drinking decisions.
Disclaimer: Alcohol Should Be Consumed Responsibly
First, a disclaimer: This article is for educational purposes only, not to encourage drinking. Consuming alcohol comes with health risks, especially in excess. However, for adults who choose to drink legally and responsibly, elucidating what’s happening inside your body can lead to smarter drinking choices. So let’s dig in!
Alcohol’s Initial Stop: The Mouth
After taking a sip of that wine, beer or cocktail, the first place alcohol hits is the oral cavity, or mouth. The tissues lining your mouth and tongue contain mucosa that can absorb a tiny bit of alcohol directly into the bloodstream. However, the vast majority will continue its journey down the esophagus on the way to the stomach.
Now, on to the throat!
Passing Through the Pharynx and Esophagus
When you swallow, the epiglottis closes off your airway and diverts the liquid into the pharynx, also known as the throat. From there it enters the esophagus, the muscular tube connecting the throat to the stomach. The esophagus efficiently transports the alcoholic beverages you ingest down into your gut.
Absorption Begins in the Stomach
The stomach marks the first major site of alcohol absorption into the bloodstream. Roughly 20% of alcohol is absorbed through the stomach lining.
The stomach is very acidic, with a pH between 1.5-3.5. This acidity irritates the stomach lining, and alcohol amplifies this irritation. Drinkers may experience nausea, indigestion or stomach pain as a result.
There is a protective mucus layer shielding cells from the acidic contents. But alcohol diffuses right through to reach the blood vessels underneath.
Now, absorption rate depends on a few factors:
- Drinking on an empty stomach increases absorption because the pyloric valve at the stomach base stays open, allowing alcohol to quickly pass through to the small intestine.
- Eating food before or while drinking slows absorption because food needs time to digest, so the pyloric valve closes and alcohol remains in the stomach longer.
This is why drinking on an empty stomach gets you intoxicated faster! But it also irritates the sensitive stomach lining more severely, making it advisable to eat before imbibing.
Okay, after getting partially processed in the stomach, it’s onward to the small intestine.
The Small Intestine Finishes Absorption
The small intestine is where the bulk of alcohol absorption occurs—around 80%. The intestine has a huge surface area covered in microscopic finger-like projections called villi.
Villi are designed to grab nutrients from food and drinks. When alcohol enters the small intestine, the blood supply in the villi grabs it and sends it straight to the liver for detoxification through the portal vein.
From start to finish, it takes about 30-90 minutes for ingested alcohol to get fully absorbed into the bloodstream and delivered to the liver.
Breaking Down Booze in the Liver
Now we arrive at the liver, the body’s main filtration organ. The liver performs 500 different functions, but one of the most important is detoxifying chemicals and drugs to render them harmless.
When blood contaminated with alcohol reaches liver cells called hepatocytes, they contain two key enzymes to break ethanol down:
- Alcohol Dehydrogenase – Converts alcohol into acetaldehyde, which is even more toxic than alcohol.
- Aldehyde Dehydrogenase – Transforms the acetaldehyde into acetate, a harmless compound.
Ideally, the two enzymes fully detoxify all the alcohol. But the speed of alcohol consumption impacts this process. When you drink faster than your liver can metabolize it, intoxication occurs as ethanol permeates your cells before getting converted to acetate.
Now let’s see where alcohol goes after the liver!
Alcohol Reaches The Heart and Lungs
The liver dumps alcohol-laden blood into the inferior vena cava, which carries it directly to the heart. With every heartbeat, the alcohol gets pumped through the pulmonary arteries into the lungs.
In the lung’s tiny air sacs called alveoli, some alcohol evaporates into your breath. This is why breathalyzers work to estimate blood alcohol levels. The remaining alcohol heads back to the heart to circulate through the body.
Alcohol Travels Throughout the Body
Once oxygenated blood leaves the heart again, it gets distributed through your arteries to all your tissues and organs. Here’s a quick look at how alcohol impacts some other body parts:
- Brain – Alcohol activates the neurotransmitters that make you feel euphoric and reduce inhibition and motor control. It suppresses glutamate which slows reaction time.
- Muscles – Alcohol may inhibit protein synthesis needed for muscle recovery and growth. It also causes dehydration and electrolyte loss.
- Intestines – Alcohol increases intestinal permeability, allowing bacteria and toxins to leak into the blood. This triggers inflammation.
- Pancreas – Heavy alcohol use can lead to pancreatitis, an extremely painful inflammation of the pancreas.
- Kidneys – Alcohol reduces anti-diuretic hormone production so the kidneys excrete more fluid, causing dehydration. Potassium and magnesium loss also occurs.
- Skin – Blood vessel dilation makes skin flushed. Dehydration and vitamin deficiency over time can make skin dry, flaky and prematurely aged.
How Alcohol Impacts Hormones
Alcohol doesn’t just alter neurotransmitters in the brain. It also disrupts hormone production in the endocrine system. Here’s what happens:
- The hypothalamus alters functions of the pituitary gland after detecting alcohol in the blood.
- This suppresses anti-diuretic hormone (ADH), leading to dehydration as the kidneys excrete more fluid.
- The pituitary gland also tells the adrenal glands to produce more cortisol and epinephrine. These stress hormones increase heart rate and blood pressure.
Hormonal changes from drinking produce many physiological effects like anxiety, sweating, nausea, and frequent urination. Hormone levels revert to normal once all the alcohol clears your system.
Factors Influencing Alcohol’s Effects
The same amount of alcohol impacts people differently based on:
- Age – Older individuals tend to feel greater motor and cognitive impairment.
- Sex – Females tend to get more intoxicated than males of equal weight because they have lower water volume in tissue and blood.
- Genetics – People inherit variations in alcohol metabolism genes that alter sensitivity.
- Full vs. empty stomach – Food in the stomach slows absorption into the bloodstream.
- Medications – Some prescriptions can enhance alcohol’s effects.
- Tolerance – Frequent heavy drinkers adapt to dissipate alcohol more efficiently.
Hangovers Explained
After a night of heavy drinking, you may wake up with the dreaded hangover. Hangovers remain somewhat of a mystery, but potential contributing factors include:
- Dehydration – Excessive urination causes fluid and electrolyte depletion.
- Gut irritation – Alcohol promotes gut leakiness and inflammation. Toxins may enter the blood.
- Sleep deprivation – Alcohol disrupts sleep patterns and quality.
- Acetaldehyde buildup – If the liver can’t clear toxic acetaldehyde fast enough, it builds up.
- Sugar crash – Alcohol causes blood sugar spikes and drops.
- Incomplete metabolism – Congeners which provide flavor and color in drinks may contribute.
- Inflammation – The immune system gets overactivated. Cytokines and prostaglandins build up.
While home remedies abound, time and rest are the only proven hangover cure. The body requires several hours to metabolize all the alcohol and rehydrate itself after a drinking session.
The Takeaway
Hopefully this trek through the anatomy provides some insight into how the ethanol in alcoholic beverages impacts your body and brain. While abstaining is healthiest, understanding how alcohol affects organ function may help guide safe and moderate consumption for adults. Always drink plenty of water and take necessary hangover precautions.