Q. Is it Earl Grey or English breakfast tea that can cause sore muscles?
A. There is one case report of a man who developed significant muscle pain and cramping in reaction to Earl Grey tea (The Lancet, April 27, 2002). We have also heard from a few readers who had similar problems.
Earl Grey tea is flavored with oil from the citrus fruit bergamot. This oil contains bergapten, a natural compound that can block the flow of potassium in and out of cells. Muscle cells rely on potassium flow, so that might explain the connection. Most people do not seem to suffer this kind of reaction, so those who do may be exceptionally sensitive.
