Researchers at U.S.-based Naturally Vitamins in Arizona claim that the amino acid, citrulline, may provide a superior support to enhance "male performance". Citrulline is found to be most prevalent in watermelons and scientists suggest that it may require three watermelons to make a difference to a man's performance. A concentrated form of citrulline in pill form is not currently available on the market but the company maintains that it could be ready be early 2001.
