Ingredient

Knotweed Extract

A potent botanical antioxidant rich in resveratrol, delivering targeted protection against oxidative stress, infrared radiation, and UV-induced damage while visibly brightening and evening skin tone.

Best For
Brigthening and Protection
Best to
Shield +Clarify
Compatability
Works with all Actives

What is it

What is Knotweed Extract

Japanese Knotweed (Reynoutria japonica) is one of nature's richest sources of resveratrol — a powerful polyphenol antioxidant. Knotweed extract acts as a multi-functional defender: it neutralizes free radicals from UV and infrared radiation that accelerate visible aging, inhibits melanin overproduction to reduce dark spots and uneven tone, and supports the skin's own repair processes. Infrared radiation (which makes up nearly half of the solar spectrum) penetrates deeper than UV and generates heat-induced oxidative stress; knotweed helps neutralize this damage at the cellular level. Its anti-inflammatory properties also calm redness and post-breakout discoloration, making it a versatile brightening and protective active.

Benefits

What does Knotweed Extract do for your skin?

A high-potency botanical antioxidant that works on multiple levels to protect, brighten, and restore evenness. Key actions include:

Neutralizes free radicals from UV exposure, pollution, and environmental stressors
Protects against infrared radiation beyond what SPF alone addresses
Inhibits tyrosinase activity to reduce melanin overproduction and dark spots
Brightens overall skin tone and fades post-inflammatory hyperpigmentation
Calms visible redness and inflammation for a more even complexion
Supports cellular repair and skin resilience with daily use
Enhances the efficacy of other protective actives like Vitamin C and SPF

How to use

How does Knotweed Extract fit into your routine?

Knotweed extract is stable, gentle, and pairs well with all actives including Vitamin C, niacinamide, and SPF. It is most commonly found in serums, targeted treatments or SPF and is applied morning and evening. For brightening and protective benefits morning application followed by sunscreen is ideal. Consistent daily use over 8–12 weeks yields the most visible improvements in tone and clarity.

Who should use it

Who should use Knotweed Extract

Suitable for all skin types. Ideal for those dealing with uneven skin tone, dark spots, sun damage, or post-breakout marks. Particularly beneficial for anyone in their 30s and beyond looking to add broad-spectrum antioxidant protection — including against infrared radiation — and brightening support to their daily routine.

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