Three burning questions for dermatologist and inclusive health expert Dr Howard Murad.

● “Can stress really affect my skin?” – KAREN, 36

It really, really, really can. An extra-crazy day may have a small effect, but what causes the worst damage is what I call cultural stress, which is the constant strain you experience when you’re in traffic and late again, or you’re answering 20 high-priority e-mails every morning. We don’t deal with this stress, and that’s deleterious. My research has found that when my patients are stressed, the hydration in their skin decreases, making their complexion duller, drier and susceptible to irritation. So I created cards with positive insights on them – such as “Why have a bad day when you can have a good day?” – and had my patients read them twice a day. I saw that by doing something as simple as that, their stress levels decreased, their skin cells were more hydrated, and their skin looked better. 

● “What is the most important step I can take to look younger?” – JANA, 52

Use a good moisturiser. It should contain antioxidants and lipids, like ceramides, to improve your skin barrier. If you can do one more thing, add a treatment that addresses your particular need, whether that’s acne, hyperpigmentation or something else. My non- skincare suggestion: Find your inner toddler. If you strive for the judgment-free joy that a two-year-old feels, the happier you’ll be and the better your skin will look. 

● “Why does nothing fix my dark under-eye circles?” – JENNIFER, 43

Because maybe nothing can. Chronic dark circles are genetic, and no product can change that. But an eye cream can help if you have darkness sometimes, or if your chronic circles are suddenly worse. These come from a lack of sleep, salty foods and eye rubbing – all of which slow down circulation and dilate blood vessels, and are noticeable because of the thin skin under your eyes. Apply a formula that contains caffeine to increase circulation or peptides, and retinyl palmitate to firm and plump.