Laser can strengthen damaged cells. Using photochemical processes, laser light inserts biophotons into damaged cells. The cells begin to produce energy (ATP), which improves their function, assists their division, strengthens the body's immune system, and causes the secretion of various hormones. The tissues are healed, and pain disappears. If damaged cells have died, the biophotons help the division of neighboring cells, generating new tissues, and thus bring about healing.