The sentence dermatologists rarely say out loud, because the industry lives on the opposite: after forty we do not need more cosmetic products, we need a better choice. It comes from Dr Cristina Garcia Millan, a specialist in aesthetic dermatology, and with it she topples an entire shelf of bottles bought out of fear rather than need.

First, the number itself is not a threshold. "Forty is not an exact boundary," Garcia Millan says. Skin does not change overnight - cell renewal slows, collagen production drops and the ability to hold moisture weakens. In women three processes overlap at once: chronological ageing, hormonal ageing and photoageing from sun collected over years.

The number that genuinely hurts arrives with menopause. When oestrogen falls more sharply, skin becomes thinner, drier and more sensitive, and collagen loss in the first five years after menopause can reach 30 percent. That is not an advert for a cream - that is physiology, and no bottle stops it. What can be done is to slow it and to avoid making it worse.

On endocrine disruptors, the subject people fear most, the doctor is measured: ingredients in cosmetics do not automatically alter the hormonal system, because dose, absorption and regulation all matter, and European rules restrict numerous ingredients. Pharmacist Amaia Frade adds the other side: "Skin is a remarkable barrier, but it is not an impermeable barrier," and points out that skin is also an endocrine organ with hormone receptors, so repeated exposure across years is not insignificant.

The routine they recommend comes down to five points and is almost insultingly simple: sun protection all year round, strengthening the barrier with glycerin, hyaluronic acid, ceramides and niacinamide, retinoids for texture and collagen in the evening, antioxidants in the morning and less aggressive exfoliation. Protect in the morning, repair at night - that is the whole philosophy.

"Small changes sustained over time usually have a far greater impact," Frade says. And that is the point that sells least: the answer is not to fear cosmetics, but to simplify the routine, choose brands that say what is inside, and focus on what you genuinely use every day. A shelf full of products standing untouched is not skincare - it is expenditure.