Is This and That Good for Healing or Prevention of This and That?

I often get a question in the following form: 

Is _______________ good for healing or prevention of cancer / atherosclerosis / osteoporosis / flu… ? 

The medical model of thinking says that diseases are entities that attack people, and thus that there are certain substances for their prevention and treatment.

Logic and nature dictate a different picture.

My definition of disease is:
Disease is a normal reaction of the body to abnormal conditions.

Thus, it is logical that there is no prevention and treatment other then the elimination of the abnormal conditions and the establishment of the normal conditions.

In other words: avoid that what harms the body and give the body exclusively what the body needs, that is what the body is biologically adapted for.

Health is the result of healthy living. There is no magic ingredient / drink / food / treatment. Miraculous is the power of the body and the willingness of every cell of the body to always fight for health.