There is an old belief among spirituals that if one meditates long enough in time he will get enlightened as soul, and even his body will heal from any illness.
From my research and experiences, and also observing many spirituals undergoing all sorts of illnesses and looking into the energies of their bodies, I concluded that actually healing the body by meditation depends on several factors:
1) How high the body vibration is. Concerning healing the body vibration is much more important than how high one’s soul is. Ultimately, many embodied fully enlightened souls like Ramakrishna for instance and others, died quite young at like 50 years old by some cancer or other mundane illness. Therefore, the higher the body vibration the quicker the healing process.
2) What amount of higher energy (prana/chi) the person can bring in meditation, or by any other energy procedure, into his body. The more he can bring and can manage by specific procedures the quicker the healing.
3) How long the person can wait, since energy healing is a treatment and can take long time, it’s not like gulping an aspirin for a headache and in 15 min you are good again. The advantage is that in such type of healing we work on the illness Causes while mainstream medicine work on the Effects; if we work only on the effects, even if the effects/pains decrease for the moment, if the causes are not fixed these will feed further the effects and the illness will return in time.
4) How high a person's practical understanding is concerning how things work in Creation. During meditation we can find out eventually the real Causes of an illness, maybe with the help of a spiritual healer, but we still need to know how to use that information.
If it’s more a superficial illness, like a cold or the like, with meditations and some herbal teas you are good again in a matter of days.
If on the other hand you have diabetes, cancer and the like, so a grave or terminal illness, then meditation certainly won’t cure you by itself no matter how good meditator you are.
In this case meditation is just a tool, and enabler for you to find out from your soul how did you diverge from your destiny path so that you got that illness as a big warning.
Only after finding out the Cause and working on the Acknowledgement and Release of that cause (which generally is a negative belief in subconscious), with no expectations and lots of humbleness, one can hope to heal also the illness physically … Certainly, one can call this releasing of a negative belief also a meditation, but I call it as a separate special releasing procedure.
I personally have been through this procedure, and also several people I personally know and studied how they made their way through such an issue.