Self-immolation : Monks in China and Japan mummified themselves in ye ancient times.

...In Japan, too, a type of sacred auto-mummification sometimes took place. A number of monks would slowly starve themselves to death by a special diet. Their bodies were embalmed and stored in an underground stone chamber for three years, then exhumed and dried, and shredded for consumption....
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...After psychological preparation, prayers, meditations the devotee entered the final stage of his life that had to last at least 1000 days. The main principles of this stage were stillness of body, detachment, contemplation, and a specific way of breathing...
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...According to the hagiographies of Buddhist auto-cremators, burning the body was rarely a spontaneous act; usually it required weeks or months of preparation, both mental and physical. The physical preparations involved a change of diet, usually expressed as "abstention from grain," accompanied by the ingestion of materials such as pine needles (a fairly common foodstuff to this day for ascetic practitioners in East Asia), herbs, resin, incense, and various types of oil...
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...The Buddhist priest and mystic, Kukai, who died on 23 April 835, is believed by his followers to have become a 'Buddha in his own body' by mummifying himself while still alive. The preserved body of Kukai is now in the internal shrine of a Buddhist temple on Mount Koya, in Japan...
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...one had to prepare very thoroughly. After psychological preparation, prayers, meditations the devotee entered the final stage of his life that had to last at least 1000 days. The main principles of this stage were stillness of body, detachment, contemplation, and a specific way of breathing. The food quantities they eat at this time slowly decrease and do not include all the nourishing components such as amyloidal substances. The devotee's organism became transformed into endogenous state - that is started consuming its own tissues...
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