Combating Winter Dullness with Brightening Serums

Dull winter skin is a look, not a diagnosis. Here is what is usually behind it, what "brightening" ingredients have actually shown in studies, and why hydration comes first.

What "Dull" Usually Means

"Dull" is a description, not a diagnosis, and there is surprisingly little research on dullness itself. What the research does show is what winter does to the conditions that make skin look flat. In a year-long study of Czech women, skin hydration and sebum production were low in winter^[1]. Reviews conclude that low humidity and low temperatures reduce barrier function^[2]. And in an animal experiment, scales appeared on the skin of hairless mice after three days in dry conditions, because surface cells were not shedding properly^[3]. All the authors of the year-long study work at a company (Contipro) and it covered Caucasian women only, and the scaling work was in mice, so take these as direction rather than a measurement of your own skin.

Start With the Surface

The outer layer of skin holds water with the help of lipids and natural moisturizing compounds. When environmental stress disturbs that system, the result is dry, flaky skin^[4]. A rough, flaking surface is one likely reason skin looks tired in winter, and no brightening ingredient fixes that. Hydration comes first. Our earlier posts on hydrating serums and chapped skin cover that step.

What "Brightening" Ingredients Actually Do

The word covers three different things:

• Loosening surface cells. Exfoliating acids (AHAs and BHAs) loosen the bonds between surface cells^[5]. Done gently, this smooths the surface. Our winter exfoliation guide explains how often.
• Evening out tone. Niacinamide works on pigment rather than on the surface. In the lab it blocked 35 to 68% of melanosome (pigment packet) transfer to skin cells, and in 4-week trials in Japanese women it reduced facial hyperpigmentation and increased skin lightness compared with a vehicle cream^[6]. The trials were small (18 subjects in one, 120 in the other) and run by Procter & Gamble.
• Antioxidants. A systematic review of seven trials with 139 volunteers found topical vitamin C produced a significant lightening of treated skin, though long-term use may be needed, and hydration improved equally in vitamin C and placebo sites^[7]. Wednesday's post covers vitamin C in more detail.

A Realistic Expectation

Brightening serums mostly target uneven pigmentation, such as leftover marks, rather than dryness. That is why the same serum may suit someone with leftover marks better than someone whose skin is simply dry. In the trials above, changes were measured over weeks, not days. If your skin looks flat because it is dry, a moisturizing routine will make a larger difference than any brightening step.

A Simple Winter Brightening Routine

• Cleanse gently with lukewarm water and pat dry.
• Apply a hydrating, tone-evening serum to slightly damp skin.
• Seal with a moisturizer, and add a thin layer on the driest patches.
• Exfoliate no more than once a week, and only if skin is comfortable.
• Use sunscreen every morning: it is the standard partner for treatments that target pigment^[8].
• Be patient: judge a new serum over four to eight weeks, and stop if skin stings or reddens.