Turmeric soap may help fade dark spots due to turmeric's active compound, curcumin, which has antioxidant and anti-inflammatory properties. Consistent use, combined with sun protection, can potentially lighten hyperpigmentation over time, but results vary.

Kojie San soap, containing kojic acid, can cause skin dryness, irritation, and increased sun sensitivity. It's crucial to use it sparingly, moisturize well, and always wear sunscreen to mitigate these potential side effects.

There isn't a single "best" soap, as effectiveness varies depending on skin type and the cause of the dark spots. Soaps containing ingredients like kojic acid, alpha arbutin, or glycolic acid are often recommended, but patch testing is crucial to avoid irritation.

Ethiglo soap typically contains skin-brightening ingredients like kojic acid and glycolic acid, aiming to reduce hyperpigmentation and even skin tone. Regular use may lead to a brighter complexion, but always follow product instructions and use sunscreen to protect your skin.