3,3′-Diindolylmethane (DIM) is a molecule named after its structure in which two indole groups are connected to a methyl group. It is commonly found in broccoli and is expected to be an anti-cancer molecule and aromatase inhibitor. It has a strong effect on estrogen metabolism and can maintain the relative balance of the body (by preventing a sharp increase or decrease in estrogen). DIM also exerts numerous anti-cancer effects in the body and is one of the reasons why this vegetable family is considered healthy. It has been pointed out that the aryl hydrocarbon receptor (AhR) has a role in some immune cells, and the activation of this receptor in natural killer (NK) cells (observed with 10μM 3,3′-diindolylmethane) can increase IFN- γ and effector functions, thereby increasing their inhibitory effect on the growth of cancer cells.