Vitamin T, or torulitine, is a substance found in egg yolks and sesame seeds. It is thought by some to improve memory and concentration, and to help strengthen red blood cells. In spite of its name, Vitamin T doesn't meet the standard definition for being a vitamin. Indeed, many don't consider it to be a vitamin at all. Despite its purported health benefits in certain circles, very little is actually known about it. Torulitine may be heard more often in its use as a slang term for testosterone or tequila.