Retinol could be claimed to “thin” one layer of the skin, though: the very top layer of dead skin cells known as the stratum corneum.
“Retinol has an exfoliating effect on this outer layer, which might technically be seen as ‘thinning,’ but this layer naturally renews itself anyway,” says Simpson.
When starting with retinol, many people experience redness, peeling and a feeling of skin tightness as it is a known irritant to the skin.
“These side effects can give the impression that the skin is becoming thinner,” Dr Simpson says.
“Over time – and it does take months, not weeks – retinol actually thickens the dermal layer,” she says.
