Vitamin C: Can it be used as a deodorant?

The vitamin C, or ascorbic acid, is one of the most studied actives in cosmetics for its ability to neutralize free radicals and stimulate collagen synthesis. It also plays a role in pigmentation regulation through its inhibitory effect on tyrosinase, the enzyme that converts tyrosine into melanin. Moreover, several studies have shown that the vitamin C can be useful for reducing skin inflammation. It is most often found in derivative forms, such as sodium ascorbyl phosphate or ascorbyl glucoside, because pure ascorbic acid is unstable and its acidic nature can cause redness, stinging, and sometimes irritation in individuals with a compromised skin barrier is damaged.

To date, no scientific data show that vitamin C has a deodorizing effect or that it could attenuate unpleasant body odors.

As a reminder, deodorants act on two mechanisms: reducing bacterial proliferation and neutralizing odor molecules produced during sweat breakdown. Contrary to popular belief, sweat itself has no odor: it is the bacteria of the underarm microbiome that metabolize compounds present in sweat to form volatile acids responsible for body odor. To fight this phenomenon, deodorants use antibacterial agents, such as certain forms of zinc, and absorbents that limit moisture, as damp areas promote microbial proliferation. The vitamin C, despite its recognized antioxidant properties, interferes neither with the growth of odor-causing bacteria, nor with the biochemical pathways that lead to the formation of odor molecules.

Nevertheless, although vitamin C cannot reduce body odor, it may be of interest in combating underarm hyperpigmentation.

The armpits are indeed an area frequently prone to hyperpigmentation. The skin here is thin and subjected to repeated friction—particularly from tight clothing or shaving—which induces low-grade chronic inflammation. This inflammation stimulates melanocyte activity through the local release of proinflammatory cytokines, promoting increased melanin production. Moreover, sweat and the microbiome specific to this area contribute to maintaining an irritated state that further increases the risk of hyperpigmentation.

In this context, vitamin C may theoretically be of interest, not as a deodorant, but as a brightening agent. As mentioned earlier, vitamin C has an inhibitory effect on melanin synthesis, in addition to its antioxidant and anti-inflammatory actions, both of which are relevant for acting upstream of hyperpigmentation.

Vitamin C therefore does not target odors but may attenuate underarm hyperpigmentation, making its use potentially relevant in deodorants.

Note : Although the skin-lightening effect of vitamin C has been demonstrated in various clinical studies, none have been conducted on the underarm area, thus warranting caution.

• SELANG T. & al. Vitamin C in dermatology. Indian Dermatology Online Journal (2013).

• CHIANG N. & al. Topical vitamin C and the skin: Mechanisms of action and clinical applications. Journal of Clinical and Aesthetic Dermatology (2017).

• LEONARDI G. R. & al. Deodorants and antiperspirants: Identification of new strategies and perspectives to prevent and control malodor and sweat of the body. International Journal of Dermatology (2021).