You don't use unwashed glasses then why drink straight from cold-drink cans? Food-safety guidance says cleaning it is very important

A chilled can of cola or another cold drink may look perfectly clean when it comes out of the refrigerator, but the outside of the can is not necessarily as clean as the drink inside it. This is something many people do not think about, especially when they are thirsty and simply open the can and start drinking from it.

Food safety guidance from the US Food and Drug Administration (FDA) and India's Food Safety and Standards Authority of India (FSSAI) puts cleaning among the basic steps for reducing the risk of food contamination. The FDA specifically advises consumers to clean the lids of canned goods before opening them.

Why the outside of a can matters

A beverage can can pass through several stages before it reaches your hand. It may be handled during transportation, placed on warehouse shelves, kept in shops and handled by different people before it is finally sold.


That does not mean every can is contaminated or unsafe. Packaged beverages are manufactured under food-safety controls, and the drink itself is protected inside the sealed container. The concern is mainly about the surface that comes into contact with your mouth.

Research published in Health Safety of Soft Drinks: Contents, Containers, and Microorganisms also notes that packaging materials, including cans and bottles, can be possible sources of contamination. The paper by Dorota Kregiel examined the microbiological and chemical safety issues associated with soft drinks, including contamination linked to containers and storage.

What about rats, dirt and urine?

There have been warnings online that cans stored in warehouses can be exposed to rodents and their urine or faeces. Such contamination is possible in an unhygienic environment, but it should not be taken to mean that drinking from a can will automatically cause a serious infection.

One disease that is associated with infected-animal urine is leptospirosis. The US Centers for Disease Control and Prevention (CDC) says the bacteria that cause the disease are spread through the urine of infected animals, including rodents. People can become infected by eating food or drinking water contaminated with such urine.

Leptospirosis can range from mild illness to serious disease. The CDC says symptoms can include fever, headache and other non-specific symptoms, while severe cases can affect organs and require medical treatment.

So the issue is not that every unwashed can is carrying leptospirosis. Rather, cleaning the part that touches your mouth is a simple precaution when the history of the can's handling is unknown.

FDA and FSSAI both stress cleaning

The FDA's basic food-safety approach is built around four steps: "clean, separate, cook, and chill." Its guidance says people should wash their hands and surfaces regularly and specifically states that canned-goods lids should be cleaned before opening.

FSSAI follows the same basic approach in its food-safety guidance, stressing the importance of keeping hands and surfaces clean and cleaning canned-goods lids before opening.

This is also why pouring a cold drink into a clean glass is a simple option. If drinking directly from the can, wiping the top properly with a clean wet cloth or washing it when practical can remove dirt and material from the outside surface before it reaches your lips.

The point is fairly simple: the drink may be sealed and protected inside the can, but the outside of the can has been exposed to the world. A few seconds spent cleaning the surface is an easy food-safety habit and avoids putting unnecessary contaminants directly around your mouth.