Understanding the causes of a dull complexion helps you identify the best solutions to restore your skin’s radiance. A ‘dull’ complexion is generally a visible sign of minor cellular or molecular imbalances, most of which are easy to alleviate with the right skincare routine.
A slowdown in the renewal of epidermal cells (keratinocytes) : the keratinisation process is disrupted. Normally, young cells gradually move up from the basal layer to the stratum corneum, where they eventually flake off before being replaced in turn. When new cells are slow to be produced, dead cells accumulate in the upper layers. They then form a thin film of keratin which reduces the skin’s ability to reflect light. The complexion therefore appears duller, as if lifeless.
A tendency towards skin inflammation: a study by Akira Matsubara et al. conducted in 2024 (1) reveals that dull skin has higher levels of interleukin-36γ. This is a marker of skin inflammation, which is also found in cases of psoriasis. At the same time, the authors identified a weakening of the skin barrier, evidenced by a reduction in certain proteins responsible for binding cells together, including filaggrin. These two factors support the likelihood of a link between inflammatory mechanisms and a loss of radiance.
Stagnation of blood microcirculation: the blood supply to the dermis plays a key role in giving the skin its healthy flush. When the blood flow through this network decreases, the skin tissues receive fewer nutrients and less oxygen. On the surface, this poor circulation results in a sallow appearance. Combined with an increase in skin micro-relief (roughness), which creates small areas of shadow, this circulatory and chromatic factor contributes to a reduction in perceived radiance (2).
Physiological ageing of the skin: the process of skin ageing alone accounts for several of the factors mentioned above. Over the years, the hydrolipidic film becomes thinner, the rate of cell regeneration slows down, the dermis atrophies, the epidermis develops roughness and skin vascularisation decreases. Thinner, more uneven and paler, the skin gradually takes on a lacklustre (or devitalised) appearance. In addition to these profound changes, research also suggests that the skin becomes more yellow and/or redder with age, whilst losing some of its natural ability not only to reflect but also to backscatter light (3).
Overexposure to stressors: the skin can also lose its radiance in response to its exposome (i.e. the totality of its environmental exposures). It is known, for example, that oxidative stress promotes collagen degradation, oxidises the lipids in the skin barrier and disrupts keratinocyte proliferation. All these factors combine to make the skin less firm, less even and, ultimately, to diminish the radiance of the complexion (4). Pollution, for example through regular exposure to fine particulate matter, is also thought to play a significant role in inducing oxidative stress and the gradual dulling of the complexion (5).
