Menthol, an organic chemical which is found in mint oils and peppermint, is able to activate a protein in our nerve cells known as TRPM8. It is the Transient Receptor Potential cation channel subfamily M member 8. This protein is activated in cold temperatures. It allows in the sodium and calcium ions and sends a current from the membrane of the nerve cells. This makes us feel cold. When we eat mint or peppermint, the TRPM8 is tricked into thinking that it is cold. This is why we feel cold when we eat or apply mint on our skins.