Blood tests are important and vital to providing medical doctors information about serious illness in the body. One should be done to rule out such things as cancer, heart disease, and liver disease before starting on a nutritional balancing program. That said, testing the hair gives you a more complete understanding how the body is processing everything you’re taking in from food to the air you breathe. It is possible to see the trends of the body including producing, processing and use of digestive enzymes, hormones, and toxic metals and chemicals. These are things the blood carries and delivers throughout the body but blood does not tell you how those things are being utilized and that’s what makes hair analysis more comprehensive.