Unpasteurized milk, also known as raw milk, is proportionally responsible for 150 times more disease outbreaks than pasteurized milk, a new report issued by the CDC’s (Center for Disease Control and Prevention) Emerging Infectious Diseases has revealed. The authors also explained that dairy-related disease outbreaks in US states where raw milk is legal occur at twice the rate compared to other states.

In this study, researchers gathered data on dairy-related outbreaks from 1993 through 2006 throughout the United States. During the study period, the USA produced approximately 2.7 trillion pounds of milk, of which about 27 billion (1%) was unpasteurized milk. They then calculated that the likelihood of outbreaks caused by raw milk products was proportionally 150 higher. Examples of raw milk products include yogurt and cheese.

During the study period:

  • There were 121 disease outbreaks related to dairy products
  • The outbreaks caused 4,413 illnesses
  • There were 239 hospitalizations
  • Three people died
  • In 73 outbreaks (60%) state authorities announced that raw milk products were to blame
  • 200 of the hospitalizations were caused by consuming raw milk products
  • The dairy related outbreaks took place in 30 states
  • Three-quarters of all the raw milk outbreaks occurred in 21 states, all of them states where selling raw milk products at the time of the outbreaks was legal
  • 7 states changed their raw milk laws between 1993 and 2006

It is not possible to determine whether unpasteurized milk is safe to consume by tasting, smelling or looking at it. Some bacteria get into raw milk during collection, even under ideal conditions of hygiene and cleanliness. These bacteria can multiply and cause illness, unless the milk is pasteurized.

Pasteurization involved heating milk to below boiling point to reduce the risk of infection and disease outbreaks caused by some bacteria.

Robert Tauxe, M.D., M.P.H., deputy director of CDC’s Division of Foodborne, Waterborne and Environmental Diseases (DFWED), said:

“This study shows an association between state laws and the number of outbreaks and illnesses from raw milk products. Restricting the sale of raw milk products is likely to reduce the number of outbreaks and can help keep people healthier. The states that allow sale of raw milk will probably continue to see outbreaks in the future.”

The researchers also found that unpasteurized milk was linked to a much higher risk of severe illnesses. It also disproportionately affected children and teenagers (people aged less than 20 years). Their study revealed that 60% of sickened patients were in this younger age group, compared to just 23% among pasteurized milk consumers.

Children have a greater risk of developing serious illness from consuming raw milk than adults.

Co-author Barbara Mahon, M.D., M.P.H., deputy chief of CDC’s DFWED Enteric Diseases Epidemiology Branch, said:

“While some people think that raw milk has more health benefits than pasteurized milk, this study shows that raw milk has great risks, especially for children, who experience more severe illnesses if they get sick. “Parents who have lived through the experience of watching their child fight for their life after drinking raw milk now say that it’s just not worth the risk.”

Written by Christian Nordqvist