The skin is the body’s first line of defense against environmental exposures. However, the skin changes considerably as we age, reducing its defense capacity. A 2021 study in mice found that sulforaphane, a bioactive compound derived from broccoli, mitigates age-related skin changes by activating Nrf2, a protein that participates in the body’s antioxidant defense system.

Researchers fed young and old mice regular mouse chow or chow supplemented with sulforaphane for three months. They assessed the antioxidant capacity and protein expression levels in the animals' skin. They also measured levels of reactive oxygen species and matrix metalloproteinase-9 (MMP9, a protein involved in tissue remodeling, inflammation, and wound healing), assessed epidermal and dermal thickness changes, and analyzed collagen content.

They found that sulforaphane reduced reactive oxygen species and MMP9 levels in older mice. It also increased the skin’s antioxidant capacity, as evidenced by enhanced Nrf2 production. They observed no difference in epidermal thickness between young and old SFN-treated mice, but dermal layers were thinner in older mice. Collagen content improved in young and old mice, with more substantial structural improvements observed in the older group.

These findings suggest that dietary supplementation with sulforaphane ameliorates age-related skin changes in mice by activating the Nrf2 pathway, enhancing antioxidant defenses and reducing oxidative stress.

Notably, the dose provided in this mouse study was very high, translating to about 2,500 milligrams of sulforaphane in humans – roughly the amount supplied in 63 cups of broccoli sprouts. Nevertheless, sulforaphane’s antioxidant-inducing capacity is well established, and consumption of sulforaphane-rich foods is associated with increased healthspan and lifespan. Broccoli sprouts are excellent sources of sulforaphane and are easy to grow at home. For tips on how to grow broccoli sprouts, check out our comprehensive Sprouting Guide, a members-only perk.