Humans have a long and complicated relationship with alcohol. Whether it is part of a social moment, relaxing alone, as part of your meal, celebrating for a special achievements and occasion, alcohol is rarely missing and it is very sought after. 

It is a psychoactive (mind-altering) substance with depressiveeffects (slows down heart rate, breathing, thoughts and actions). The common denominator of all the alcoholic beverages is a chemical component called ethylic alcohol or ethanol. This is the only type of alcohol we can ingest without being poisoned.

Ethanol is the bio-product of a process called alcoholic fermentation, a process that takes place when certain microorganisms called saccharomyces attack rotten fruits eating their sugar and releasing ethanol and CO2 as a waste product.

When we drink alcohol, it flows from your mouth to your stomach where 20% of it will be absorbed entering into your blood. The rest of it will be absorbed by your small intestine. Once into the blood stream the ethanol will make its way to the liver which will try to get rid of it. To do so, the liver needs to break the ethanol molecules down using an enzyme called alcohol dehydrogenase, which will oxydise ethanol that will then turn into a highly toxic component called acetaldehyde. The latter will then be metabolized by the liver using an enzyme called acetaldehyde dehydrogenase.

If the liver is exposed to more alcohol than its enzymes can handle in order to metabolize it safely, molecules of ethanol and acetaldehyde will continue their journey in the blood stream circulating in your whole body.

The first sign of alcoholic effect is an increased blood flow to the skin, that’s why highly vascularized areas of your body (such as the face) turn red, as well as feeling hot resulting in sweating and stinking of alcohol.

Another effect is the decreased release of the hormone vasopressin, which helps the kidney to regulate the amount of water in your body. This leads to a failure to absorb the amount of water that the kidney receive resulting in an increased urination and contributing to dehydration.

When the alcohol reaches the heart it expands and relaxes blood vessels (a phenomenon called vasodilation), resulting in a drop of blood pressure.

The heart will also pump the alcohol to your lungs, where it will be expelled from your body together with the CO2, giving that lovely, distinct, stinging and appealing smell to your breath.

But the real fun starts when alcohol reaches the brain. As for all the drugs (Yes! Alcohol is a drug), alcohol alters the normal functioning of the neurotransmitters in the brain and this leads to all the classic behaviors of a drunk person.

It increases the production of a neurotransmitter called GABA, which causes sleepiness, slow movements and thoughts, and delayed reaction times.

It decreases the production of the neurotransmitter Glutammate, which is responsible for disinhibition and the exaggerated emotional response. It also decreases our attention and compromises our memory.

It increases the production of Dopamine, which causes a sense of happiness and gratitude, as well as hyperactivity and euphoria.

When you wake up the following morning the real fun starts: headache, dry mouth, clumsiness, upset stomach, nausea, and most importantly a huge sense of regret.

The Hangover

As mentioned before, alcohol diminishes the production of vasopressin, which leads to dehydration. When our body is dehydrated, it tries to take water from whatever source possible, and one of the places where your body will source water is your brain. This leads the brain to shrink in size, creating a lot of tension between the membranes that line your brain and keep them attached to the skull (meninges). The dehydration is also made worse by vomiting, which is extremely common when people go way over the limits. 

Also, alcohol il extremely aggressive for you stomach inner lining (mucosa) and can cause irritation. The following morning it is very possible that you wake up with an upset stomach, heartburn, andstomach pain. The intoxicating effects of the acetaldehyde will cause the sense of nausea.

The only remedy out there that is 100% effective against hungover is: TIME. There tons of fake remedies out there that will try to sell the best solution for an hangover: coffee, cold shower, eating, going for a walk, and God knows what else. They certainly help, but the truth is that there is no scientifically proven method that is valid against the hangover. All you can do is to take care of the symptoms: pain killers for headaches, plenty of water, eat something nutritive and not too demanding for your stomach.

The organ that is damaged the most for alcohol is your liver, and this damages can lead to conditions such as hepatic cirrhosis, cancer, or hepatitis. Cancer can also arise in the digestive tract as a result of alcohol consumption.

In the heart, it increases the chances of having hypertension, strokes and heart attack. It also affects the reproductive system with decreased sex drive, infertility and erectile dysfunctions (in men).

Alcohol can lead to addiction too, and it can give rise to mental health problems such as depression, psychosis, and eating disorders.

Can It Be Good For Your Health?

Red wine, when consumed in moderation, is actually thought to be good for your heart and health in general. This is due to polyphenols, antioxidants present in red wine, specifically Resveratrol, an antioxidant which might help to prevent damage to blood vessels, reduce low-density lipoproteins (LDL) cholesterol and prevents blood clots.

The reason why Resveratrol is more present in red wine is because this antioxidant comes from the skin of grapes used to make wine, and red wine is fermented with grape skin longer than white wine, hence red wine contains more Resveratrol.

The scientific consensus on this is quite mixed and more research is needed to prove or disprove the positive effects of Resveratrol.

How Long Does it Take To Metabolize Alcohol

Your body generally takes one hour to process one standard drink, or more conveniently one unit, which equals to 10ml or 8g of pure alcohol.

In the table below you can find some references on what 1 standard drink can be equal to. 

Units

It can be hard to keep track of the alcohol ingested, especially because it comes in different glasses and different servings. A simple way to measure alcohol is through units, which is usually expressed by the standard measure of alcohol by volume (ABV). It indicates the amount of pure alcohol as a percentage of the total volume of liquid in a drink.

It is simple to work out how many units of alcohol are there in a drink. You simply have to multiply the total volume of a drink (in ml) by its ABV (in %) and dividing the result by 1000.

               Strength (ABV) x volume (ml) / 1000 = units

For example, if I want to find out how many units of alcohol are contained in my small glass of red wine, knowing that it has a strength of 12% and I am drinking 140ml:

                    12 (%) x 140 (ml) / 1000 = 1.68 units

For How Long Alcohol Is Detectable In Your Body?

Alcohol stays in your body longer than you think. You can find below how long alcohol can be detectable for with these different tests.

How much alcohol consumption is considered a safe limit?

According to the NHS, to keep health risks from alcohol to a low level if you drink most weeks, men and women are advised not to drink more than 14 units a week on a regular basis.