Does aloe vera help to diminish brown spots?

A succulent plant from the Asphodelaceae family, the aloe vera is highly appreciated by art enthusiasts for the aesthetic appeal it brings to a room. However, its utility goes beyond that: its leaves contain a translucent gel with a viscous texture that has moisturizing, softening, and repairing properties when applied topically. Commonly used pure or to formulate cosmetic care, aloe vera gel is a versatile treatment that can be used on different parts of the body, such as the face, hair, or even the nails. Among its many benefits, some also mention its lightening properties.

Indeed, according to certain studies in vitro, aloesin, a molecule found in aloe vera gel, is capable of suppressing the hydroxylation of tyrosine into DOPA and the oxidation of DOPA into dopachrome, a metabolite of melanin biosynthesis. As a reminder, the melanin produced during the process of melanogenesis is responsible for skin pigmentation. When it is synthesized excessively or disorderly, due to prolonged or repeated UV exposure or hormonal changes, it can cause brown spots. These initial results regarding aloe vera seem promising in terms of its effect on hyperpigmentation.

However, this effect was not observed in topical application during the clinical trials conducted on this subject. The results of two of these are compiled in the table below and demonstrate a lack of effect of aloe vera on brown spots. Each of these studies involved a significant number of volunteers with hyperpigmentation, a condition whose progression was quantified using the MASI score (Melasma Area Severity Index). This scale, commonly used in research to measure the severity of melasma, takes into account 3 criteria: the affected area, the degree of pigmentation, and its uniformity.