How testosterone and estrogen affect your skin, and what changes when they shift

People tend to encounter their hormones as a series of separate mysteries. Skin that broke out at 14 and cleared at 20. Skin that reliably breaks out the week before a period. Skin that changed in a way nobody warned about at 48.

These are not separate events. They are one system, and it has two main levers.

What estrogen does

Estrogen is the structural hormone. Its receptors, both ER alpha and ER beta, are expressed on virtually every cell type involved in skin repair: fibroblasts, keratinocytes, inflammatory cells, tissue stem cells and vascular endothelial cells.¹

What it does with that reach is shift a balance. Estrogen induces transforming growth factor beta and tissue inhibitors of matrix metalloproteinases, while inhibiting the matrix metalloproteinases themselves. In plainer terms, it turns up the machinery that builds collagen and turns down the machinery that dismantles it, which supports the production and maintenance of collagen types I and III.¹

It also increases skin thickness, moisture and hydration through hyaluronic acid and other mucopolysaccharides.¹

So when estrogen falls, several things happen at once rather than in sequence: less collagen made, more broken down, less water held. That is why the change at menopause feels abrupt even though the hormone declines gradually. Collagen content drops roughly 30 percent in the first five years after menopause and continues falling by about 2 percent annually, leaving skin thinner and structurally weaker.¹ We cover that transition specifically elsewhere.

What androgens do

Androgens, testosterone chief among them, have a narrower and more visible job: they run the sebaceous gland.

Androgen stimulation increases sebaceous gland activity, and the resulting accumulation of sebum and keratin within follicles creates the conditions for comedone formation and bacterial growth.² That is the entire mechanism behind hormonal acne, and it explains why acne arrives at puberty in everyone, why it is worse in conditions involving higher androgen levels, and why anti-androgen treatment works when it works.

Everyone has both hormones. What differs is the ratio, and the ratio moves.

The monthly experiment

The menstrual cycle is the clearest natural demonstration that this is real rather than folklore.

In a study of adult women with acne, 65 percent reported their acne was worse with their period. Of those, 56 percent said the worsening came in the week before menstruation, 17 percent during, 3 percent after and 24 percent throughout the cycle.²

Self-report is one thing, counting is another. Earlier quantitative work found 63 percent of women had an increase in inflammatory acne lesions during the late luteal phase, with measured increases of roughly 23 percent in total lesions, 25 percent in inflammatory lesions and 21 percent in comedonal lesions.²

The same face, the same routine, a quarter more lesions depending on the week. That is worth holding onto the next time a product appears to stop working.

Everything that moves the ratio

Puberty raises androgens sharply, which is why acne starts. Pregnancy raises estrogen substantially, which is why some people describe unusually good skin and others develop melasma. Polycystic ovary syndrome involves elevated androgens, with acne and hair pattern changes among the visible consequences. Hormonal contraception moves the ratio in either direction depending on the formulation. Perimenopause and menopause drop estrogen. Testosterone declines slowly with age in men, without the abrupt inflection.

Deliberate changes count too. Gender-affirming hormone therapy produces predictable and well-documented skin changes on a known timeline. Anabolic steroid use raises androgens substantially and produces acne to match, often on the back and shoulders.

The list looks miscellaneous. Mechanistically it is one variable.

What this changes in practice

Judge a product over a full cycle, not a week. Something introduced in the follicular phase and assessed in the luteal phase will look like a failure regardless of whether it works. This is the single most common way people abandon products that were fine.

Ask what is driving it before treating the surface. Acne that begins in adulthood, arrives with hair pattern changes or cycle irregularity, or resists reasonable treatment deserves an evaluation of the cause rather than more aggressive topical work.

Time procedures where you can. Skin is more reactive in the days before a period for some people. It is a reason to shift a booking, not to avoid treatment.

Expect structural change to need structural answers. Falling estrogen produces collagen loss, and topical care does not replace collagen. What actually stimulates collagen is a separate question with a real answer.

Where this stops

Hormones explain a lot, which makes them easy to over-apply.

Not every skin problem is hormonal, and an aesthetics practice is not the right place to be diagnosing or managing endocrine disease. Suspected PCOS, thyroid disease, unexplained hormonal symptoms and decisions about hormone therapy all belong with primary care, endocrinology or gynecology.

Routine hormone panels for people without symptoms are also not the answer. Testing without a question produces numbers rather than information, and normal ranges are wide.

What is useful in a practice like this is narrower: knowing the pattern well enough to recognize when skin behavior is following a hormonal rhythm, to time and interpret treatment accordingly, and to say plainly when something needs evaluating somewhere else.