Menstrual cycle, ovulation, pregnancy, menopause... The causes of "late onset" acne
Particular skin sensitivity can be observed in certain families. This predisposition particularly affects the reactivity of the sebaceous glands to androgen hormones. When these glands are more numerous, larger or more sensitive, sebum production can be higher. In this context, several members of the same family may have experienced persistent or recurring blemishes at different times in their lives.
Hormonal imbalances including PCOS
Hormonal blemishes are often linked to an imbalance between male hormones, known as androgens, and female hormones, particularly estrogen. Testosterone and DHEA are produced naturally in women. They can be converted locally into dihydrotestosterone, a more active form that strongly stimulates the sebaceous glands. Conversely, estrogens have a regulating effect by limiting this stimulation. The balance between these hormones directly influences the condition of the skin.
In some cases, this imbalance is part of a broader hormonal disorder, such as polycystic ovary syndrome (PCOS). PCOS is a common endocrine disorder in women of childbearing age, characterised by excessive androgen production, irregular menstrual cycles, and ovulation abnormalities. The excess androgens observed in this context can promote increased sebum production and the appearance of blemishes. However, not all women with PCOS develop skin problems, and conversely, not all hormonal blemishes are indicative of PCOS.
Other hormones involved
Cortisol, a hormone released during prolonged stress, acts indirectly. Repeated exposure to stress is associated with increased inflammation and changes in the skin environment. These changes can contribute to the appearance or worsening of blemishes. A link between skin condition and the balance of the gut microbiota, i.e., all the microorganisms living in the intestine, is also possible.
Role of insulin
Insulin is a hormone involved in regulating blood sugar levels. Frequent stimulation of its secretion, particularly after consuming foods rich in rapidly absorbed sugars, is associated with increased androgenic activity. In some people, this stimulation can contribute to increased sebum production and the appearance of blemishes. This mechanism is also observed in some women with PCOS, in whom insulin resistance, i.e., reduced effectiveness of this hormone, is frequently described.


















