Disclaimer: this article may kill your buzz.

I am most certainly not here to knock alcohol. Those close to me can affirm that I enjoy a sloppy Santa or two (boxed wine mixed with whiskey) around the holidays (or year-round, really). I feel that acquiring knowledge allows you to make informed and educated decisions. We're all grown adults and we can choose to ingest whatever the fuck we want, whenever the fuck we want. Might as well learn what the hell you're putting in your body. 

 

Shocker: alcohol isn't good for us. Alcohol contributes "empty calories" to your diet and can likely lead to liver cancer, cirrhosis, and a plethora of other chronic diseases. But why is alcohol detrimental to our health, and why do some people become addicted to alcohol while others do not?

As with most addictive substances, there is a blatant disconnect between how our brain and our body perceive alcohol. Alcohol - chemically known as ethanol - is considered a toxin by the body and is preferentially metabolized in order to reduce tissue damage. Only minutes after ingestion, alcohol reaches the brain as a powerful stimulant. Alcohol is the only nutrient (substance that contributes calories) that acts as a stimulant and therefore causes the brain to "crave" alcohol. 

 

But wait...isn't alcohol a depressant?? Actually, the way in which alcohol affects neurotransmitters lend it to being considered both a stimulant and depressant. Here's why:

 

Alcohol as a depressant

• Suppresses the "excitatory" neurotransmitter- glutamate- which would normally increase brain levels and activity. 
• Increases the "inhibatory" neurotransmitter- gamma-Aminobutyric acid (GABA)-which reduces energy levels and increases feelings of calmness 

Alcohol as a stimulant

• Increases release of dopamine in your brain's "reward center". Other drugs that do this include cocaine and crystal meth. Over time, it takes more and more alcohol to release the same amount of dopamine until the dopamine effect diminishes completely. 

I don't think it's a surprise to anyone that the effects of alcohol on our brain lend to alcohol's addictive nature. It both stimulates our reward center while creating a feeling of calmness. As fun as drinking can be, alcohol ultimately fucks your body up. Here's why.

 

ALCOHOL METABOLISM 101

 

 

 

 Metabolism includes all reactions - both catabolic (breaking down) and anabolic (building up) - that occur after we ingest a nutrient.   While there are several pathways that alcohol can be metabolized in the body, the most common involves two enzymes: alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH). Collectively, these enzymes break apart the alcohol molecule and allow it to be safely eliminated from the body.

Alcohol use and alcohol-related problems are strongly pre-determined based on individual variations in alcohol metabolism. These variations are both genetic and environmental - we all have slightly different variations of ADH and ALDH in our body. Moreover, our present nutritional status and overall health also plays a role in how effectively alcohol is cleared from our system.

In the first step of alcohol metabolism, alcohol (ethanol) is converted into a toxic compound and known carcinogen called acetylaldehyde by ADH.  Acetylaldehyde is then further broken down into a less active byproduct, acetate, by the enzyme ALDH. Finally, acetate is metabolized to water and carbon dioxide to be eliminated by the body.

It's not quite that simple, though. There are a host of other side reactions that take place as alcohol is metabolized. The enzymes cytochrome P450 2E1 (CYP2E1) and catalase also break alcohol into acetylaldehyde, but only after a person ingests a large amount of alcohol. Small amounts of alcohol are also removed by binding to fatty acids to create fatty acid ethyl esters (FAEEs). These fatty acid compounds play the largest role in deterioration of the liver and pancreas from alcohol.

The Genetic Component:  

I find it extremely interesting that the inherent genetic differences of the enzymes ADH and ALDH have a striking role in predicting alcoholism and the chronic health consequences of alcohol ingestion. Not only can we vary in the amount of these enzymes, but there are myriad variations of each enzyme itself. Some of the enzyme variations work more or less efficiently than others; this means that some people can break down alcohol to acetylaldehyde, or acetylaldehyde to acetate, more quickly than others.

The goal is to have acetylaldehyde in your system for the shortest duration possible. Therefore, a fast ADH variation will cause acetylaldehyde to accumulate quickly in the body. This can make drinking physically unpleasant - facial flushness, nausea, and rapid heart beat are common symptoms, regardless of alcohol intake. ADH1B*2 is a variation of ADH that is common in people of Chinese, Japanese, and Korean descent but rare in people of European or African descent. ADH1B*3 is another very efficient variation of ADH and occurs in 15-25% of African Americans. These populations are somewhat "protected" against alcoholism by the effects of alcohol intake, however, they are at a higher risk of alcohol complications due to the accumulation of acetylaldehyde if they do choose to drink.

The opposite can also occur: efficient variations of ALDH have been positively correlated with alcoholism, as the body is able to efficiently turn acetylaldehyde into acetate - therefore minimizing the negative physical effects of alcohol. ALDH1A1*2 and ALDH1A1*3 are examples of these variations and are typically seen in African American populations.

Health Consequences of Alcohol:  

• Alcohol metabolism and Cancer
• acetylaldehyde is a carcinogen that interferes with DNA replication and inhibiting the repair of damaged DNA
• Reactive-oxygen species are produced when alcohol is metabolized by CYP2E1. ROS damage proteins and DNA
• Fetal Alcohol Syndrome
• The presence of alcohol in the bloodstream interferes with the quality and quantity of nutrition that crosses the placenta. This results in slow fetal growth and permanent fetal damage
• Alcoholic Liver Disease and Pancreatitis
• The liver is the main place of alcohol metabolism. The accumulation of FAEEs contributes to fatty liver and increases risk for liver cirrhosis
• The pancreas is also involved, however, most research suggests that dietary habits and smoking are main contributors to the irreversible damage done to the pancreas
• Malnutrition and Obesity
• Alcohol contains 7 calories per gram and carries no nutritional benefit
• Increases the amount of fatty acids circulating in the bloodstream and does not regulate blood glucose control, causing our brain to increase hunger signals to increase amount of blood glucose. 

So, in conclusion: drink whatever the fuck you want. #themoreyouknow