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The vibration of a cat’s purr can speed up the healing process not only for cats but for other animals as well. Research indicates that even humans can benefit.
If you are recovering from an injury, you should hug a purring cat. Consistent vibrational sound frequencies of 25-150 Hz, which is the range of a cat’s purr, aid in the healing of bones, tendons, ligaments and muscles, as well as providing pain relief.
Why Cats Purr
Purring would not have evolved unless it provided some sort of survival advantage. It is commonly assumed that cats purr to express contentment, but this does not explain why cats also purr when giving birth, frightened or severely injured.
Healing After Injury
Cats’ bones heal faster and more easily after fractures than those of dogs. Veterinary medicine researchers note that 90% of cats that plummet from extraordinary heights survive despite serious injuries. There is also evidence that cats are less likely to suffer postoperative complications after surgery than dogs. This rapid healing ability may be attributable to purring.
Bone Strength and Recovery
Dr. Clinton Rubin and his colleagues have discovered that sound frequencies of 20-50 Hz can increase bone density. An amusing study in which researchers placed chickens on a vibrating plate for 20 minutes each day found that the chickens grew stronger bones as a result. This finding was replicated in a study of rabbits, in which bone strength increased by 20% after exposure to the 20-50Hz sound frequency. The study also found that the frequency stimulated the healing of broken bones as well as the speed of bone regeneration. This discovery has significant implications, given the large numbers of people who suffer from osteoporosis (bone loss) as they age.
Cats suffer far less often from diseases of the bones than dogs, and given the effect that the purr frequency has on bones, it is likely that purring plays a role in this. There are a number of osteo diseases that are rare in cats but common in dogs, including scapulohumeral joint luxations and hip dysplasia. Cats are also less likely to suffer from osteosarcoma, osteoarthritis and myeloma (a tumor of the bone marrow’s plasma cells).