Many physicians used hair analysis inappropriately. In conventional medical circles, doctors who used hair analysis were considered quacks. It's the 1990s now, lab standards and technology have improved and we have more realistic expectations of this screening tool. Hair analysis is not the best way to find nutrient minerals, although some patterns will give important clues about the patient's nutritional status and health. Testing blood cells and other methods are better for finding out about essential minerals.
Hair analysis is, however, a good, noninvasive, inexpensive way to screen for heavy metal toxicity.
Heavy metal toxicity can affect every enzyme system in the body. Every so often you will get a patient who is being treated for candidiasis by a nutritionist or colon therapist. They are chronically ill, fitting typical description of a candida patient in William Crook's book, The Yeast Connection. More often than not they are carrying a shopping bag full of vitamins and herbs designed to kill yeast, aid digestion, restore normal flora, and support the immune system. In spite of heavy nutrient therapy, the patient will still be ill.