If your dog shows unusual dislike or manifests an odd behavior. Try to be more mindful, the dog is probably making you aware about the potential threat that a situation presents to you. Researchers have found out that our bodies, particularly cancer tissue, release a specific chemical that is different from a healthy tissue. Surprisingly, dogs are good at recognizing the difference between malignant tissue and normal tissue. In some instances, a trained dog is able to successfully detect colon cancer in people with more than 90% accuracy rate. Moreover, they do not only detect cancer, a dog can alarm you when you have low blood sugar and seizures.