Scientific studies have proven that dogs can sense diseases, such as cancer, through their keen sense of smell. Some dogs can even be trained to let people who have epilepsy know when they are about to have a seizure. Dogs can detect the smell of diseases through an ability to detect chemicals, which is called volatile organic compounds, or VOCs. This helps us smell chemicals, as it helps dogs smell chemicals and diseases. Dogs can sense diseases faster than humans because of their amazingly strong sense of smell. If a dog is only focusing on a certain part of your body, that could mean you have a disease, or some leftover food or grease from lunch.
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