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What is Acetaldehyde?
Acetaldehyde is a common toxin and carcinogen with a negative impact on our health. Acetaldehyde is found in alcohol, smoke, air pollution, and certain foods & beverages.

Acetaldehyde is a common toxin

Acetaldehyde & ALDH2 Deficiency

Acetaldehyde is a toxic molecule that is always circulating in the blood in low concentrations. A Group 1 carcinogen, acetaldehyde can cause damage in our bodies and continued exposure can lead to cancer and other disease. In our modern environment, acetaldehyde enters the body from a number of sources. Acetaldehyde is also produced inside our own bodies through regular processes. Those with ALDH2 Deficiency cannot properly break down acetaldehyde, which leads to accumulation in the body and increases the risk of long-term diseases. Those with ALDH2 Deficiency should be aware of the major sources of acetaldehyde. 

Sources of Acetaldehyde

Sources of Acetaldehyde  

Drinking Alcohol 

Drinking alcohol spikes blood acetaldehyde concentrations to very high levels for short periods of time, typically 2-4 hours. Ethanol found in alcoholic beverages is quickly converted into acetaldehyde. In those with ALDH2 Deficiency, the acetaldehyde accumulates rapidly, leading to physical symptoms known as Alcohol Flush Reaction (Commonly referred to as 'Asian Flush' or 'Asian Glow'). Acetaldehyde concentrations can be more than 10 times higher in people with ALDH2 Deficiency.


Acetaldehyde is the most common toxin in cigarette smoke and is the cause of many of the negative health risks associated with cigarette smoking. When tobacco is burned, acetaldehyde is produced and enters the smoke, which is then inhaled. Individuals who smoke, or are frequently inhaling second-hand smoke, are continuously being exposed to more acetaldehyde.

Breathing Polluted Air

Acetaldehyde is one of the most common indoor and outdoor air pollutants. Indoor air concentrations of acetaldehyde in the home and the workplace are often even higher than outdoor concentrations. Major indoor sources of acetaldehyde in the air come from building materials, flooring, paints and treated wood. Second-hand smoke is a major contributor to indoor air acetaldehyde. Outdoors, acetaldehyde is commonly released into the air during production and transportation of the chemical. In addition, acetaldehyde is released into the air via vehicle emissions, power plants, factories, and the burning of plant or trash material.

Food and Diet

Fermented foods and beverages, dairy products, coffee, tea, bread, ripe fruits, and some processed foods contain varying levels of acetaldehyde. Diets high in refined sugars can lead to an increase in acetaldehyde. Yeast populations called Candida albicans live naturally in the human gut, and are usually kept in check. Candida albicans convert sugar from the diet into acetaldehyde through fermentation. A diet higher in sugars can lead to an overgrowth in Candida albicans populations, which convert more sugar into acetaldehyde in the gut. This acetaldehyde can cause damage to the gut and can eventually make its way into the body and other tissues. Use of antibiotics can also disrupt the balance of Candida albicans in the gut and lead to overgrowth. To learn which foods are high in acetaldehyde, visit Acetaldehyde in Foods.

Why is Acetaldehyde Dangerous?

Healthy Liver and Liver Cirrhosis

In addition to being a toxin, Acetaldehyde is a Group 1 carcinogen, which means it can cause cancer. Continual exposure to acetaldehyde has been associated with serious long-term health risks, including liver cirrhosis, gastric and esophageal cancers, osteoporosis, and Alzheimer's disease. Acetaldehyde causes scarring to the liver, which can decrease liver function. To learn how Essential AD2 improves liver health, click here.

Acetaldehyde is a reactive molecule. It can create 'Free Radicals', which react with other molecules and cause oxidative damage. These free radicals can damage proteins and DNA, which gives acetaldehyde its carcinogenic properties. Anti-oxidants in human cells can protect from oxidative damage, but the anti-oxidants need to be regenerated to continue to function properly. Continual exposure to acetaldehyde can lead to an imbalance in anti-oxidants.

To learn more about how acetaldehyde does damage to our liver, proteins, and DNA (Learn more). For more information about ALDH2 Deficiency and long-term health risks associated with acetaldehyde exposure, please visit our page on ALDH2 Deficiency.


Essential AD2 is clinically proven to reduce acetaldehyde in those with ALDH2 Deficiency