CAM is short for "complementary and alternative medicine" and covers all healing modalities other than the Western allopathic model, or "conventional" medicine (at least for us). Western allopathic medicine is based on a mechanistic model of the human body, where the different body parts can be treated independently from one another by specialists (i.e. the heart by a cardiologist, the kidneys by a nephrologist, the feet by a podiatrist, the mind by a psychologist or psychiatrist). Diagnosis is based on detailed examination of all visible parts of the physical body. Treatments are geared towards eliminating or reducing symptoms; they are not geared towards healing the root cause of the matter, because that is not part of the belief system.
Treatments range from cutting out diseased tissue, to injecting or administering substances that reverse the symptoms (but also usually have side effects - undesirable for the most part). This is similar to bringing your car in for a check-up and having its oil and windshield wiper fluid checked and refilled, the tire pressure verified, and the spark plugs exchanged.
This model is successful in emergency medicine (accidents, broken limbs) and for acute illnesses, where no time is to be lost to save a life. It is not so effective for afflictions that have a connection with the psyche (most of them) - did you ever consider that heart disease might have to do with matters of the heart (not the organ, but the emotional heart)? Here, the model of one-standard-treatment-cures-all does not work so well, as we can see from the varying successes of treating cancer, heart disease, psychological and psychiatric disorders, diabetes, auto-immune diseases and on and on.
CAM works with a different model of the body. In this model the body is more than a sum of its physical parts, it is a mind-body-spirit entity that exists in an energetic universe. Some examples of CAM modalities are homeopathy, healing with herbs, acupuncture, reiki, Ayurveda, but also massage therapy, music therapy, yoga and meditation. These methods all help to rebalance the underlying energy system of the body. It has been said that about 85% of all illnesses are due to emotional imbalances, which means that the underlying emotional blockage or psychological conflict needs to be resolved to dissolve the physical symptom without reoccurrence. It has already been acknowledged that lifestyle changes can do wonders - regular meditation reduces stress, a better diet and more exercise give you more energy, and less stress and more harmony in life are beneficial in general. That's all spiritual stuff. There is definitely more to our bodies than what we can see.
Please also read my older related post on Healing as a Balancing Act.