You have cold receptors in your skin and these cold receptors are different from your skin's heat and pain receptors. Now we have an explanation for the deception in advertisements for body wrapping to lose weight.
You go to a special salon where an attendant measures and weighs you, rubs a cream on your fatty areas and then wraps you in cloth. You feel alternately hot and cold and one hour later, they remove the cloth wrap, measure your waist circumference and show you that you have lost a couple of inches. You are delighted, pay your money and go home. The next day, you are very upset because you measure your waist again and find that your waist circumference has returned to its previous size and that you have lost no weight at all.
You are smart enough to realize that the decrease in your waist size was caused by the wrapping which squeezes fluid from your skin and the fat underneath. You reason correctly that as soon as you drink fluids, the tides come back in and the skin and fat fill again with water and you now learn that losing water does nothing to help you lose fat. BUT how do you explain the alternate hot and cold feelings that you felt under the wrapping?
The nerves in your body have specific functions. Motor nerves carry messages from your brain to tell your muscles when to contract. Sensory nerves transmit messages to your brain to tell you what you touch and feel. The sensory nerves that carry pain, heat and cold messages are called type C and feelings of pain and heat are sent from one nerve to another by chemicals called neurotransmitters. The neurotransmitter that carries pain and heat messages is called substance P. Applying a cream containing an extract from peppers called capsaicin uses up substance P in nerves (3,4). You can buy this inexpensive .025% capsaicin cream over-the-counter, without a prescription, and apply it several time a day. First you will feel burning and itching because you are stimulating substance P, but eventually the capsaicin cream uses up substance P and blocks the pain and heat receptor. You can control pain and burning with several applications of the cream each day. Doctors prescribe the cream to relieve itching and pain. An article in a recent American Journal of Physical Medicine and Rehabilitation shows that pepper cream controls muscle pain. Another article in the European Journal of Clinical Pharmacology shows that pepper cream helps to control the pain of shingles, diabetic nerve damage, osteoarthritis, post-herpetic neuralgia, arthritis and psoriasis. The cream may cause burning, so do not apply it to broken, raw or open skin. You can also get the same burning and relief from pain by applying a cream that contains aspirin. Oil of wintergreen cream is methyl salicylate, an aspirin. It also causes heat and burning when you apply it, and as you keep applying it, it blocks pain.
This explains the burning you felt in your skin when you had your body wrapping for weight reduction. You want to know what caused the cooling that you also felt. Ardem Patapoutian of the Scripps Research Institute in La Jolla CA reported that he discovered a cold receptor in the skin. He found the cold receptor in nerves that responds to temperatures between 8 and 28 degrees centigrade. Menthol binds to the cold receptor in skin, which is different from the hot receptor that aspirin and the pepper extract, capsaicin bind to. So now you know why applying menthol and capsaicin creams together will give you alternating hot and cold chills. No longer will you waste your money on body wrapping, a scheme that is advertised to help you lose weight, but doesn't.
1) Arden Patapoutian, CELL March, 2002.
2) David Julius. UCSan/Fran. Nature April, 2002.
3) WY Zhang, ALW P. The effectiveness of topically applied capsaicin – A meta-analysis. European Journal of Clinical Pharmacology 46: 6 (JUL 1994):517-522.
4) BJ Mathias, TR Dillingham, DN Zeigler, AS Chang, PV Belandres. Topical capsaicin for chronic neck pain: A pilot study. American Journal of Physical Medicine & Rehabilitation. 74: 1 (JAN-FEB 1995):39-44