Experts share the single most important skincare product for every decade after 40.

It’s probably not news that your skin changes as you get older. Sometimes that's a good thing—goodbye, acne!—but other times, not so much. “As you age, collagen and elastin production decrease, cell turnover slows down, and skin hydration diminishes,” explains  cosmetic dermatologist Dr Sejal Shah. UV rays and free radicals in the environment also take a toll over the years.

By the time you hit the big-40, these factors may be responsible for a duller complexion and the appearance of pesky fine lines. You might also notice some discolouration. "Skin gets blotchy because of excess brown melanin production and gets red from damage to blood vessels,” explains dermatologist Dr Neal Schultz.

Luckily, you can adjust your skincare routine to ward off or tackle these signs of ageing. The most crucial step—at any age—is to slather on sunscreen every day, since it's the best anti-ager out there. What else is a must to protect your skin? We asked dermatologists to pick the most important type of product (besides sunscreen) to add to your arsenal in every decade.

If you're in your 40s...

Lost your glow? It’s a common conundrum. “In your 40s, skin can become dull looking, and uneven skin tone and wrinkles are more predominant,” says dermatologic surgeon Dr Dendy Engelman. The fix: antioxidants. "These fight against free radical harm and start to repair damaged cells," which helps to brighten and repair the skin, says Engelman.

Vitamin C is an antioxidant powerhouse, but you may also want to seek out products with green tea, vitamin E, resveratrol, polyphenols and caffeine.

If you're in your 50s...

Exfoliating has always been important, but this is the time to really take it up a notch. “Hands down the single most important skincare product is a chemical exfoliant, but here's the catch: it needs to be used every day,” Schultz says. “So that means it has to be gentle enough for daily use without irritation yet still strong enough to effectively remove the ageing, tired looking, dulling, discolouring, clogging dead cells that build up on the skin's surface."

Physical exfoliants, like scrubs, are too harsh to use daily, which is why Schultz believes a chemical exfoliant is a better choice. Using one daily "is essential in order for the exfoliant to ‘talk to’ the second layer of skin where firming collagen and plumping hyaluronic are made, and only daily stimulation of cellular turnover will motivate that,” he says.

The key ingredient to look for is glycolic acid. Start using it now (though if you started in your 40s that's even better) and plan to continue through the decades to come.

If you're in your 60s or older...

This is often the stage when new lines and wrinkles seem to appear overnight. By now, the loss of collagen and elasticity is more obvious and the skin may be drier as oil production naturally slows down.

“In your 60s, the skin becomes more fragile and delicate, so look for products that hydrate and repair the skin,” Shah says. You can continue using other products, including antioxidants and exfoliants, but may need to cut back if it's too drying. For example, you may need to transition to a milder exfoliant or use it less often.

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