Recent Advances on the Nutritional Effects Associated with the Use of Garlic as a Supplement

and its constituent compounds. Both water- and lipid-soluble allyl sulfur compounds are effective in blocking a

myriad of chemically induced tumors. Part of the protection from these compounds probably relates to a block in

nitrosamine formation and metabolism. However, blockage in the initiation and promotion phases of the carcino-

genicity of various compounds, including polycyclic hydrocarbons, provide evidence that garlic and its constitu-

ents can alter several phase I and II enzymes. Their ability to block experimentally induced tumors in a variety of

sites including skin, mammary and colon, suggests a general mechanism of action. Changes in DNA repair and in

immunocompetence may also account for some of this protection. Some, but not all, allyl sulfur compounds can

also effectively retard tumor proliferation and induce apoptosis. Changes in cellular thiol and phosphorylation

stains may account for some of these antitumorigenic properties. The anticarcinogenic potential of garlic can be

influenced by several dietary components including specific fatty acids, selenium, and vitamin A. Since garlic and

its constituents can suppress carcinogen formation, carcinogen bioactivation, and tumor proliferation it is imper-

ative that biomarkers be established to identify which individuals might benefit most and what intakes can occur