Could your diet be ageing your skin? What the evidence says

We're a nation obsessed with stopping the signs of ageing. The UK Botox market is forecast to reach nearly £295m by 2031, external and YouGov's recent anti-ageing report, external suggests 28% of us spend more than £25 a month on skincare and supplements to keep them looking young.

But could changing your diet be as effective as a cream or serum?

It's normal for your skin to look less plump, smooth and firm as you age.

That's partly because from your mid-20s, collagen – a protein that gives skin structure and strength – starts to break down faster than your body can replace it. This means that the thickness and strength of our skin decline at a rate of about 1.5% a year.

But other factors also have an impact, says dermatologist and nutritionist Dr Thivi Maruthappu. Genetics, sun damage and pollution, external all play a part – as do our diets.

They say you are what you eat – and sometimes the impact is written on our faces.

Too much refined sugar, for instance, can cause what people call 'sugar sag', says Dr Maruthappu.

Otherwise known as glycation, external, it's where sugars like fructose and glucose react with proteins like collagen and cause cell dysfunction.

"It makes collagen in the skin become quite stiff. When that happens, skin doesn't bounce back as well," she explains.

The result? Wrinkles.

A diet of ultra-processed red meats and fried foods, meanwhile, might be the cause of other skin concerns like dullness, rosacea, breakouts and a sallow complexion, explains Dr Maruthappu.

"UPFs are generally not good for gut health, and when our gut is out of whack, it can contribute to more inflammation in the skin. This can accelerate skin ageing – a process known as inflammageing, external."

Regular after-work beers or weekend wines might also be showing signs on your face.

An industry-funded, observational study found people who drank more than eight units a week had increased facial lines, external.

It's not clear why, but Dr Maruthappu suggests it could be because alcohol is converted by the body into sugar. That's as well as the possible dehydration, oxidative stress, inflammation and sleep disruption that alcohol can contribute to.

Unfortunately, drinking loads of water in the aftermath isn't going to be as helpful for your skin as it is for that hangover, either.

Being hydrated is important for loads of reasons, but the evidence of how fluids impact our skin isn't quite as clear-cut as many influencers would have you believe.

While some studies suggest drinking more water may help skin hydration, there's little evidence, external that simply chugging litres of it is a shortcut to younger-looking skin.

"Drinking two litres of water every day might make you feel better (not to mention help your kidneys) but it's not what the supermodels say – that you're going to look amazing for it," says Dr Maruthappu.

So, what does work?

You might be surprised to learn that when drunk in moderation, coffee could have anti-ageing benefits, external. It's full of antioxidants, which have been found to reduce cellular oxidative stress, external and neutralise free radicals.

"These are mostly environmental toxins, pollution and UV radiation that damage collagen," Dr Maruthappu explains.

To make your diet more antioxidant rich, she recommends eating dark berries (think blueberries, external), drinking green tea, external and cooking with sumac, external, a spice often used in Iranian dishes.

As for eating collagen itself, the benefits have long been debated by experts but a recent scientific review of 113 studies suggested collagen capsules and powders carry some benefits for skin – if used consistently.

"They're not going to make you look 10 years younger, but they do improve skin hydration and reduce the appearance of fine lines – the evidence for it is growing," adds Dr Maruthappu.

Sadly, your elevens (those two lines between your eyebrows) and crow's feet aren't going to disappear just because you've swapped cake for carrots.

Wrinkles are predominantly caused by a loss of collagen, says Dr Maruthappu, and that's a natural part of ageing.

But that's not to say your skin can't be improved by changing what you eat.

"Your skin is renewing itself every 30 to 40 days so you could always do something beneficial to your skin by improving your diet – and you might see it very quickly, in a couple of weeks," suggests Dr Maruthappu.

She recommends adopting the GLOW acronym:

Ultimately though, it's about taking a holistic approach.

"Your nutrition is important because there are so many foods that can accelerate skin ageing," she says. "But it's a piece of the puzzle, not the entirety. You've got to get the basics right, like sun protection, first."

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