Anti-vitamins found in food

Several food items contain chemical substances which act against or act as antagonists for vitamins. Such substances are known as ant-vitamins.

Some decaying plant parts contain anti-vitamins. Dicoumarin found in decaying or spoiled sweet clove is one of the anti-vitamins. Dicoumarin is chemically related to vitamin K. Dicoumarin acts as an antagonist to vitamin K. Therefore ingestion of Dicoumarin can result in relative deficiency of vitamin K. Vitamin K is essential for blood clotting mechanism (hemostasis). Therefore consumption of spoiled sweet clove can result in hemorrhagic disease. There no human cases were reported but there are cases reported on cattle, which fed on spoiled sweet clove develop a hemorrhagic disease.

Thiamine deficiency is relatively common due to consumption of thiamine anti-vitamins. Plants such as ferns and bracken contain antimetabolites of thiamine, if eaten in quantity, can lead to thiamine deficiency. But this is not for human as they do not consume ferns or bracken plants. But this is again important for cattle.

Some micro-organisms found in gut can produce thiaminase (anti-vitamin for thiamine) which can destroy thiamine. If thiamine intake is adequate, this will not be a problem. In Japan it is believed that infection with such organisms is a cause of thiamine deficiency. Thiaminase is also present in raw and fermented fish (carp:above picture), relished in the Japan and china.