Urea as a dietary supplement for humans.

Use of urea as a nonprotein supplement in the feeding of beef cattle and other ruminant animals is a technique of practical application. Urea has also been used in human feeding studies. Its early employment was that of an added source of amino nitrogen in studies designed to determine minimum requirements of the essential amino acid. Later studies suggested that it's inclusion in diet containing sub-optimal amounts of protein supplied by various food product could result in the establishment of apparent improvement in protein nutriture. Other studies indicate that urea is not unique in this ability but is only one of many possible sources of amino nitrogen and is actually one of the least effective. Known and potential hazzards definitely prohibit the use of urea supplements to food products other than in research or clinical laboratories at the present time.