Vitamin C

Vitamin C has a wide range of effects, including preventing spots (inhibiting melanin synthesis), promoting collagen synthesis, lightening the color of existing spots (lightening melanin pigments), antioxidant properties, and promoting cell turnover.
Humans cannot produce vitamin C. If you want to deliver it to your skin intensively, it is recommended to combine it with skin care products, and if you want to distribute it throughout your body, it is recommended to take supplements.