Dihydroquercetin glucoside(DHQG) is in a class of chemicals known as a flavonoid that is found in various food items including onions. DHQG is an ingredient in products marketed toward hair loss.
- The in vitro evidence suggests that DHQG can prevent some levels of reduction in the concentration of the important growth factor IGF-1 after induction of oxidative stress in hair follicle dermal papilla cells. Furthermore, DHQG can reduce levels of TGF-β1. This protein induces the hair follicle to move from the growing stage (anagen) to the transition stage (catagen), indicating a potential for prolonging the growing stage of the hair follicle. Additionally, DHQG was found to reduce dihydrotestosterone (DHT) levels in cells treated with testosterone, indicating that it may also have 5α-reductase inhibitory properties. These findings, however, have not been confirmed in humans.
- The only clinical studies completed involving DHQG used it in combination with several other ingredients that may enhance hair growth, so it is impossible to know if any positive effects are due to DHQG alone.