Canadians should not drink raw or unpasteurized milk — especially children, pregnant women, older adults and people with weakened immune systems since they are at a higher risk of developing food poisoning. Vulnerable groups especially, should also be aware that raw milk or unpasteurized milk products may be sold at farm stands or farmers’ markets and they should reduce their risk by asking if the products are pasteurized before buying them. Learn about the symptoms of foodborne illness. The most common symptoms include stomach cramps, nausea, vomiting, diarrhea and fever and headaches. The symptoms can vary from mild to severe.