Foods high in carotenoids give a healthy glow

According to a new study from the University of St Andrews, the secret to a bright complexion lies not in what happens on the outside, but on the inside - by munching our way through plentiful supplies of tomatoes and carrots.

"Most people think the best way to improve skin colour is to get a suntan," says Dr Ian Stephen, who led the study. "But our research shows that eating lots of the right fruit and vegetables is actually more effective."

For Dr Stephen, good examples of the healthy, attractive skin tone achieved by eating the right foods include those of Hollywood stars Keira Knightley and TV presenter Myleene Klass. But what exactly is it about these vegetables that causes this coveted glow?

The researchers at St Andrews established for the first time that yellow pigments, or carotenoids, from certain fruit and vegetables play a crucial role in producing a more golden skin tone.

The pigment - contained in carrots and tomatoes, as well as pumpkins, plums, oranges and some dark leafy greens - is a powerful antioxidant that soaks up dangerous compounds produced when the body combats disease. It is also known to be important for our immune and reproductive systems and research suggests it could help helpful in preventing cancer.

We've all heard the saying that eating too many carrots will turn you orange, and there is an element of truth to that. If you eat foods high in carotenoids in very large amounts, you can develop an orange skin tone similar to an over-the-top fake tan.

But the researchers discovered that eating smaller quantities on a regular basis produces a more subtle yellow hue without the risk of toxicity - or the possibility of looking like an oompa loompa. It took just two months of increased consumption to produce visible results.

As well as helping to improve your general health and looks, though, the study identified that eating certain vegetables could also have a significant impact on your love life.

Dr Stephen discovered that people whose skin sports this golden glow are considered more attractive than those with a darker, so-called 'healthy' tan.

Using specialist computer software, the researchers asked 40 Scottish volunteers of both sexes to manipulate the skin colour of male and female Caucasian faces to make them look as healthy and desirable as possible.

The volunteers chose to increase the rosiness and yellowness of the skin, creating a series of ideal complexions. But the tone they preferred was the golden variety created by eating lots of fruit and veg."Given the choice between skin colour caused by suntan and skin colour caused by carotenoids, people preferred the carotenoid skin colour," says Dr Stephen.

"So if you want a healthier and more attractive skin colour, you are better off eating a healthy diet with plenty of fruit and vegetables than lying in the sun."

It's not just humans that get to enjoy the benefits of carotenoids. They are also responsible for the pigment brightly-coloured birds and fish use to display their health and attract mates in the natural world.

"This is something we share with many other species," says Professor David Perrett, who was also on the research team at St Andrews.

"For example, the bright yellow beaks and feathers of many birds can be thought of as adverts showing how healthy a male bird is. What's more, females of these species prefer to mate with brighter, more coloured males. But this is the first study in which this has been demonstrated in humans."

The findings could potentially open up new strategies for encouraging young people to eat more fruit and vegetables, tying in conveniently with government thinking in Scotland at the moment.

"Telling people they might have a heart attack in 40 years' time if they don't eat more healthily is one thing," says Dr Stephen.

"What we can do is say, 'This is what you could look like in a couple of months if you increased your fruit and veg intake'."

So ditch the sunbathing, forget about the all-over California tan and reach for the carrots and tomatoes instead. We're off to the greengrocer ...

This article was first published in Scotland On Sunday, 06 February, 2011z