Yoga considers that most diseases are due to insufficient life force, either in the body as a whole, or a blockage of life force to one part of the body. This leads to a lowered body resistance or immunity to disease.

Those practicing yoga have learned many centuries ago that most diseases are due to reduced immunity. Medical science is gradually coming to the same conclusion.

When the whole body has lowered life force, the result is a lowered vitality level, poor health and susceptibility to infection. No infections would occur if the body's life force is high enough to fight off the infection. Pathogens (bacteria, viruses and so on) are a normal part of life and will only cause trouble when the body's resistance is too low to keep them in check.

The best way to increase the general life force of the body is by good nutrition, sufficient deep steep, a positive mental attitude and yoga.

A blockage of life force to one part of the body, such as the thyroid gland, is usually caused by a slight misalignment of a vertebra which impinges on the nerve that travels to that particular organ. This causes interference to the life force (nerve impulses) to the organ. As a result, the organ not functioning at its optimum level. If the spinal misalignment is not corrected, the organ may develop pathology. It is much more difficult to correct at this stage.

The ancient yogis were well aware of the importance of the spine in relation to disease, since most of their asanas or postures were designed to make the spine more flexible to prevent spinal misalignments. Some of the asanas will even correct minor spinal misalignments.

The spine is so important for a high vitality level, good health and the correction of many health conditions that a whole science of healing has been developed to correct spinal misalignments. In fact, chiropractic is now the second largest healing profession after medicine and the fastest growing healing profession in the world.