Which chemical peel is known for having the smallest molecules?

Glycolic acid is recognized for having the smallest molecules among the options listed, which allows it to penetrate the skin more deeply and effectively than the others. Its low molecular weight facilitates better absorption into the skin, making it particularly effective for exfoliating the top layers and promoting cellular turnover. This characteristic is what sets glycolic acid apart in the realm of chemical peels, enabling it to be beneficial for various skin concerns such as acne, hyperpigmentation, and fine lines.

While salicylic acid is also used for its penetration abilities, its molecules are larger than those of glycolic acid. Trichloroacetic acid, although effective at deeper levels, is significantly larger in molecular size and typically used for medium to deep peels. Lactic acid, while beneficial for mild exfoliation and skin hydration, has larger molecules compared to glycolic acid and is not as penetrating. Thus, glycolic acid stands out due to its molecular size, leading to its efficacy in deeper skin treatments.