In the Mahaparinibbana Sutta, it is suggested that there is a strong relationship between life and the will
to live, mentally. Both Ananda and the Buddha remark, "the Tathagata could, if he so desired, remain throughout a world-period or until the end of it" (some translations I've seen say 100 years, but if the word used there is kappa, then that's a considerably longer time than 100 years). Before they both say this, in an earlier passage, the Buddha relinquishes his will to live. Later on, when Ananda finds out about this and asks the Buddha to continue living, but the Buddha says it is something that cannot be undone.
So, is it true that the sickness can be created or overcome by mental discipline? I am extremely disturbed by the claims by Asian Buddhists that meditation or traditional medicine can cure AIDS or cancer. However, there are many strange unexplainable cases in medicine of spontaneous recovery that may suggest this.
For instance, a woman in Northern Ireland was recently diagnosed with a rare form of untreatable cancer which she spontaneously recovered from:http://www.independent.co.uk/life-style ... 72237.html
Her immune system was somehow able to destroy a tumor which was inoperable by the doctors themselves. She attributes her recovery to prayer.
The best things in life aren't things.