Unpasteurized milk poses serious health risks without benefits

COLUMBUS — With disease outbreaks linked to unpasteurized milk rising in the U.S., a review published in the Jan. 1, 2009 issue of Clinical Infectious Diseases examines the dangers of drinking raw milk.

Health hazard

Milk and dairy products are cornerstones of a healthy diet. However, if those products are consumed unpasteurized, they can present a serious health hazard because of possible contamination with pathogenic bacteria.

An average of 5.2 outbreaks per year linked to raw milk have occurred in the U.S. between 1993 and 2006 — more than double the rate in the previous 19 years, according to co-authors Jeffrey T. LeJeune and Paivi J. Rajala-Schultz of the College of Veterinary Medicine, Columbus.

Contamination can occur at the time of collection, processing, distribution or storage of milk, the authors write.

Pathogens

Many pathogens can be found in the dairy farm environment, which can contaminate the teat skin of dairy cows and consequently the milk at the time when cows are milked.

For example, Salmonella and E. coli have been reported in pooled milk collected from farms. Outbreaks of salmonellosis, campylobacteriosis and E. coli related to raw milk consumption have been reported since 2005.

Circumvent the law

Although the sale of raw milk was illegal in 26 states as of 2006, the authors note those who are opposed to pasteurization have found ways to circumvent the law and obtain raw milk.

For example, participants in “cow-share” programs pay for the upkeep of the cow and receive raw milk in exchange, rather than buying raw milk outright.

Raw milk advocates claim unpasteurized milk cures or prevents disease, but no scientific evidence supports this notion.

Testing

Testing raw milk, which has been suggested as an alternative to pasteurization, cannot ensure a product which is 100 percent safe and free of pathogens.

Pasteurization remains the best way to reduce the unavoidable risk of contamination, according to the authors.