Food Safety

Risks Associated with Unpasteurized Milk: Questions and Answers

What is raw milk?

Raw milk is milk that has not been pasteurized (heat-treated). In Canada, it is illegal for anyone to sell raw milk to consumers. Both federal and provincial laws state that raw milk must be pasteurized before it is sold. Pasteurization heats milk to high temperatures and kills bacteria that can cause disease, making it safer to drink.

Is drinking raw milk good for you? Is it safe?

No. Raw milk may contain bacteria, such as Salmonella, E. coli, and Listeria monocytogenes which can cause serious disease. These bacteria can infect the lining of the intestines (gastroenteritis), infect the blood (septicaemia), infect the lining of the brain and spinal cord (septic meningitis) and may even cause death, especially in the elderly and young children. Pasteurization kills these harmful bacteria.

What are the signs and symptoms of infection?

Symptoms of infection vary from acute to chronic, and include severe diarrhoea (which may be bloody), stomach cramps or abdominal pain, vomiting, fever, weakness and chills. Dehydration is a consequence of water loss from vomiting and diarrhea that may be considered severe in some children and the elderly.

Are some people more at risk than others?

Yes. Children, the elderly, pregnant women, and people with weak immune systems should avoid drinking raw milk because they are at an increased risk of developing more serious illness. For example, listeriosis (a food-borne illness caused by Listeria monocytogenes bacteria) can cause septicaemia, meningitis and may even result in death in these individuals. If a pregnant woman becomes infected, it can result in stillbirth or miscarriage. The Public Health Agency of Canada states that about 5-10 percent of people infected with a strain of E.coli 0157, develop Hemolytic Uremic Syndrome, which is a serious complication that can lead to kidney failure and death.

Can the bacteria from drinking raw milk be passed on to others?

Yes. If someone becomes ill from drinking raw milk, the infection can be passed from person to person by hand-to-mouth contact. Fecal-oral spread from person to person happens especially when someone has diarrhoea and is not washing their hands properly or maintaining good hygiene. Disease can also be spread to those who are taking care of a person who is ill with diarrhoea. Individuals can also become carriers of disease, and pass the disease to another person without showing signs of illness.

What should I do if I drink raw milk and develop symptoms?

Raw milk is a health risk and should not be consumed; however persons who show symptoms should see their doctor or go to an urgent care centre to be assessed. While mild dehydration may be a minor complication, the more severe previously mentioned complications are always possible, especially for people considered to be at higher risk of illness.

What is pasteurization?

Pasteurization heats milk to very high temperatures to kill the bacteria that causes disease without significantly altering the nutritional content, flavour or quality of the milk. Rapid cooling of the milk helps prevent spoilage and keeps it safe to drink. The process was named after its inventor, French chemist and microbiologist Louis Pasteur. Before pasteurization was adopted in the early 1900s, there were many outbreaks of milk-borne disease and death in Canada. With pasteurization, public health in Canada took a giant step forward. It should be noted that pasteurized milk should remain refrigerated.

Is raw milk nutritionally superior to pasteurized milk?

No, there is no evidence that raw milk is nutritionally superior. Any supposed health benefit is greatly outweighed by the overwhelming evidence that drinking unpasteurized milk can make you ill. Pasteurization destroys disease-causing organisms. It does not affect the quality of nutrients present in milk, such as calcium, protein, riboflavin, niacin, folic acid, vitamin B6, pantothenic acid and vitamin A. About 20 per cent of vitamin C is destroyed during pasteurization, but milk is not a significant source of vitamin C.

Is it legal to sell raw milk cheese in Ontario?

In some cases, yes. However, certain raw milk cheeses are permitted provided they meet both the federal and provincial legislated requirements for manufacturing and aging.

What should I do if I find unpasteurized milk products for sale?

It is illegal to sell, deliver or distribute unpasteurized milk in Ontario. You can report unpasteurized milk sales to the Ontario Ministry of Agriculture, Food and Rural Affairs (OMAFRA) complaint line at (519) 826-3100 or 1-800-466-2372 or contact your local public health unit.  For a list of local health units, visit:

For More Information

Call ServiceOntario, Infoline at 1-866-532-3161
In Toronto, 416-314-5518
TTY 1-800-387-5559
In Toronto, TTY 416-327-4282
Hours of operation : 8:30am - 5:00pm