What Is Potassium Benzoate? Uses, Foods, and Side Effects

Potassium benzoate prevents or inhibits the fermentation, acidification, or other deterioration of foods. It is particularly known as a fungistatic, which prevents fungi from proliferating or growing and causing food spoilage. 

In the past, potassium benzoate was used less frequently than sodium benzoate. However, it has grown in demand and is now used as a substitute for sodium benzoate in acidic foods where the sodium level needs to be lower.

Potassium benzoate can be found in many foods and beverages, mostly mass-produced products:

• Sodas
• Flavored beverages
• Milk and dairy products such as cheese
• Juices and jellies
• Prepared salads
• Emulsified sauces
• Dressings
• Orange juice
• Mayonnaise
• Some baked goods

It is safe to consume potassium benzoate in small amounts. The Joint FAO/WHO Expert Committee on Food Additives and European Food Safety Authority have approved it as a preservative that can be used in a variety of goods.

However, the long-term effects of potassium benzoate on health have not yet been determined by researchers and medical professionals.

The potential benzene content in food and beverages was previously one of the main concerns regarding benzoate salts. Benzene is a known carcinogen. When benzoate salts such as potassium and sodium benzoate are used as preservatives, vitamin C is often included. According to the FDA, foods and beverages that contain both vitamin C and benzoate salt and are exposed to heat and light produce unusually high levels of benzene.

The International Council of Beverages Associations states that they are aware of the connection between potassium and sodium benzoate salts and production of benzene from vitamin C and are taking precautions to reduce the risk to the general public. However, there is little risk in the benzene levels that are now allowed in beverages.

The majority of human studies to date have concentrated on the dangers of drinking benzene, sodium benzoate, or benzoate in high doses.

According to older studies, the development of attention deficit hyperactivity disorder (ADHD) in children may be greatly affected by substances such as potassium benzoate. Benzoate preservatives were also discovered to have a detrimental effect on the behavior of 3-year-old children. Benzene can also cause allergic reactions in young infants and has been linked to changes in cognitive function.

According to the CDC, the following side effects may appear minutes or hours after consuming large doses of benzene:

• Vomiting
• Stomach upset
• Dizziness
• Sleepiness
• Convulsions
• Rapid or irregular heartbeat
• Death, in extreme cases

While benzene levels in foods and beverages are too low to pose a health risk, it underscores the need  for additional research. 

It is also best to exercise caution when consuming foods that contain potassium benzoate.