How Alcohol Affects Our Digestive System
Alcohol is a substance / depressant, as opposed to food which can be digested by our body. Alcohol is, instead, absorbed into the bloodstream and along our digestive tract from the moment that it enters our mouth.
Ethanol (pure alcohol) and acetaldehyde (a highly toxic and carcinogenic by-product created in the process of breaking down alcohol) cause damage to cells, tissues and organs as they travel through the digestive system.
Mouth and throat
When you drink alcohol, your mouth and throat are the first points of contact, and a small amount of alcohol is absorbed directly through the walls of the mouth.
Microorganisms in the mouth convert some of the alcohol into acetaldehyde, which can cause cell damage and prevent cell repairment. Over time, this could lead to cancers of the mouth and throat, including the root of the tongue and tonsils.
Oesophagus
Alcohol can directly damage the cells lining the oesophagus, which is a risk factor for cancer. Alcohol consumption can also cause acid reflux, a condition that sends stomach contents including acidic gastric juice back up the oesophagus, which can also cause cell damage.
Stomach
About 20% of alcohol is absorbed directly into the bloodstream through the stomach lining. The amount of food in your stomach affects how quickly alcohol is absorbed and how long it takes for it to enter the intestines. If there is no solid food in your stomach, it is easier for alcohol to enter the small intestine and, subsequently, the bloodstream quickly.
Alcohol irritates the stomach lining and causes inflammation. It also affects the production of stomach acid, which reduces the stomach's ability to kill bacteria, which will in turn allow harmful bacteria to enter the upper small intestine.
Liver
Over 90% of alcohol is broken down by enzymes in the liver and then disposed of from our body through excretion. No matter how much you drink, your liver can only metabolise about one standard drink (i.e. 14 grams of pure alcohol) per hour.
When the liver breaks down alcohol, it is converted to acetaldehyde. It is produced by the partial oxidation of ethanol by the liver enzyme alcohol dehydrogenase. As liver cells attempt to repair damage caused by acetaldehyde, they undergo a process of replication and division. The more often they try to fix this damage, the higher the chance that errors will occur in their DNA. These errors can accumulate over time, increasing the risk of developing cancer.
