2025.04.27
What Are the Harmful Effects of Acetaldehyde on the Body?
We previously discussed the harmful nature of acetaldehyde in our earlier article: What is the harmful substance acetaldehyde? (https://antioxidantres.jp/column013/).
So, what specific negative effects does acetaldehyde have on our body?
First, in the short term, acetaldehyde causes symptoms associated with alcohol intoxication.
Headaches, nausea, heart palpitations, and facial flushing after drinking alcohol occur because acetaldehyde dilates blood vessels.
If acetaldehyde isn’t effectively broken down within the same day, these symptoms linger, causing a hangover.
While a hangover is unpleasant, acetaldehyde has even more alarming health implications.
This is its carcinogenicity (cancer-causing potential). Acetaldehyde is known to be carcinogenic.
People who cannot efficiently break down acetaldehyde and consume large amounts of alcohol are exposed to high acetaldehyde levels, increasing their risk of developing cancers such as esophageal cancer, breast cancer, liver cancer, stomach cancer, and colorectal cancer.
The initial environmental risk assessment of chemical substances conducted by Japan’s Ministry of Health, Labour and Welfare (from fiscal years 1997 to 2000) highlighted an especially high risk for esophageal cancer associated with acetaldehyde exposure.
As previously explained in articles about alcohol metabolism, individuals who have low alcohol tolerance lack the ability to efficiently break down alcohol and acetaldehyde. Forcing oneself to continue drinking despite this genetic predisposition not only leads to feeling unwell but significantly increases cancer risk.
Moreover, acetaldehyde generates hydrogen peroxide within the body.
Hydrogen peroxide is one of the major sources of oxidative stress.
Acetaldehyde acts on liver cells, creating reactive oxygen species (ROS). These reactive oxygen species interact with certain enzymes, forming hydrogen peroxide that spreads throughout the body, damaging and destroying cells.
In other words, acetaldehyde significantly contributes to the “rusting” of the body through oxidative stress.
Acetaldehyde is a type of organic compound known as an aldehyde. Another well-known aldehyde is formaldehyde, which is associated with “sick building syndrome.”
Aldehydes, in general, are toxic to living organisms. According to the Ministry of Health, Labour and Welfare’s initial environmental risk assessment (fiscal years 1997 to 2000), direct exposure of eyes and mucous membranes to acetaldehyde caused irritation, skin redness, and even pulmonary edema (fluid accumulation in the lungs).
The body naturally has mechanisms to detoxify acetaldehyde, which forms during alcohol metabolism. However, if you continue drinking when your body’s ability to metabolize acetaldehyde is overwhelmed, you remain continuously exposed to carcinogenic risks and oxidative stress.
It’s crucial to recognize that besides the risk of alcohol dependence, acetaldehyde itself poses severe health risks.
The recommended daily alcohol intake according to national guidelines is approximately one “go” (180 ml) of sake, or up to two glasses of wine.
