A dose produces poison. – Paracelsus, 1538
There are several molecules that humans consume that are both food and medicine. Coffee and alcohol are two great examples. The antioxidants in coffee provide many health benefits, while caffeine can be fatal in high enough doses. Obviously, dosage is important. The same goes for alcohol.
How alcohol affects the body and brain
To begin, let’s look at what alcohol does in the brain, specifically how it interacts with three different neurotransmitters.
First, in low doses, it enhances the effect of the neurotransmitter GABA. Why is this important? GABA is the main inhibitory neurotransmitter in the brain. Whenever and wherever it works, it effectively shuts down that part of the brain.
When we start drinking, the first effects we notice occur because GABA inhibits activity in our cortex. The first effect is relief worry; changes in us personality and the decision is made with additional doses.
At high doses, the parts of the brain that control movement and coordination are affected. Finally, at very high doses—the exact amount can vary for different people—the parts of our brain that control breathing and heart rate are inhibited, and we’re at risk of death.
Secondly, alcohol also stimulates the release dopamine. This action may underlie our feelings of pleasure.
Finally, alcohol in high doses also inhibits the neurotransmitter glutamate. This neurotransmitter is essential for the production of memories. That’s why we can’t remember what happened when we were drunk.
Next, let’s see what happens when the alcohol molecule enters the body.
Alcohol travels to the stomach and liver, where an enzyme called alcohol dehydrogenase converts it into an aldehyde—a type of organic compound often composed of carbon, oxygen, and hydrogen, among other elements—that is very irritating to our tissues. This aldehyde is metabolized to acetate and then to carbon dioxide and water. Part of the acetate turns into fatty acids, which accumulate in the liver, fat pads and other organs.
Is drinking alcohol good for you?
As you read about the various physical and cognitive effects of alcohol, you may wonder: benefit people who drink? To answer this question, it is important to consider the dose, sexage and tissues involved.
According to the National Institute Alcohol abuse and alcoholism, less than 7 drinks per week for women and less than 14 drinks per week for men is considered “low-risk drinking.” At these doses, many epidemiological studies have reported some health benefits, including:
- The risk of heart disease is reduced because alcohol increases the level of HDL, the so-called good cholesterol. This benefit was especially noticeable postmenopausal women.
- Moderate alcohol consumption improves insulin sensitivity and reduces the risk of type 2 diabetes.
- Light to moderate alcohol consumption reduces the stickiness and aggregation of platelets, temporarily thins the blood and reduces the risk of clotting. (Note: There is an obvious downside to this effect – for example, if you get into an accident.)
- Moderate consumption can reduce the number of colds by 60 percent. Red wine, but not white, provides the body with enough antioxidants to help strengthen the immune system.
- Forty years of research involving more than 360,000 people have shown that moderate drinking reduces the risk of Alzheimer’s disease by twenty-three percent. This benefit is reduced if you have two copies of APOE-e4 gen.
- Moderate alcohol consumption reduces the risk of developing gallstones by 33 percent.
- Alcohol, especially wine, can help prevent kidney stones.
- Urinating more increases the volume of urine. A high urine output reduces the saturation of problematic stone-forming solids such as calcium or oxalates. (However, this only works if you drink plenty of fluids to reduce the dehydrating effects of alcohol.)
When is drinking alcohol harmful?
Adverse effects are dose-, time-, and tissue-dependent.
Alcohol consumption, like all drugs, has a tolerance effect. This is usually when problems arise.
The body, especially the liver, quickly adapts to a person’s level of consumption – meaning that larger and larger doses are required to achieve the same effect. Because the liver is more efficient at removing alcohol from the blood, the brain requires more to experience the pleasurable effects of alcohol on GABA and dopamine function.
Because of the constant presence of acetaldehyde and acetate in the liver, long-term high-dose alcohol consumption causes inflammation and fat deposition within the liver. Over time, chronic inflammation causes a condition called cirrhosis, which eventually leads to functional failure.
The effects of aldehyde on the blood vessels underlie the linear relationship between alcohol consumption and the risk of hypertension. In addition to causing extensive inflammation, it alters the levels of aldehydes estrogenincrease the risk of breast cancer; they can also damage DNA. Often, the affected tissues are directly exposed to aldehyde, which leads to cancer of the colon, esophagus and throat.
Basic studies of alcoholism
Finally, when it comes to the brain, alcohol shuts down neurons in a dose-dependent manner. This action leads to poor judgment, slower reaction times, and accidents and deaths.
Things we still don’t know about the effects of alcohol
There are, of course, some caveats to all of this.
First, many early alcohol studies had methodological flaws because they did not take into account that people who consume low to moderate amounts of alcohol may have other healthy habits, e.g. diet and regular exercise. On average, drinkers exercise more than non-drinkers, for example.
It is also difficult to know what the control group should be: very low drinkers or pure abstinence. Some people abstain because of health problems, and in general, abstinence has a higher rate of death and chronic disease than non-drinkers.
Finally, it should be noted that young people, especially generation Z, consume less alcohol than previous generations and less. Apparently, these young people prefer marijuana more than alcohol, with a large number of them preferring cannabis and THC drinks.
Is it a safer choice? The the alcohol and marijuana debate Still evolving – but as I’ve been telling my readers for the past few decades, the brain often tricks you into eating things your body doesn’t like.
