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Suffering from dry skin? You could splash out three-figure sums on extravagant unguents, advertised by A-listers that immaculately made-up department store assistants in lab coats promise will solve your problem.
Or you could pop to your local chemist and pick up a product that not only has A-list endorsement but is so proven to solve problems that it's actually available on prescription - and it will cost you less than a fiver.
The name of this magic cream? Aveeno, founded in 1945 by two American brothers who worked with a dermatology clinic to create a bath treatment based on finely milled oatmeal.
Aveeno Soothing Bath Treatment is still available (£13.49 for eight sachets, amazon.co.uk) but in the past 70 years, the company has been taken over by Johnson & Johnson, launched a raft of new products, including that sub-£5 cream, a shower oil and a dedicated baby skin range, and published a number of scientific papers, proving the efficacy of their products.
Oh yes, and in 2013, it signed up Jennifer Aniston as the face - and body - of the brand in America.
What makes Aveeno so special? The key ingredient is oat extracts known as avenanthramides, naturally occurring chemicals that have been shown to be potent anti-irritants.
Oat particles cling onto dirt and dead skin cells so they can be washed away, but its their active ingredient, something called beta-glucan, that makes oats such a winner when it comes to managing our skin.
When eaten (as porridge) beta glucan has been associated with lowering cholesterol, tackling obesity and helping improve the body's reaction to allergies. But when you apply it to the skin, it not only penetrates into the lower layers, but also forms a fine layer on the top, meaning it can simultaneously moisturise and soothe skin, while helping to repair the skin's barrier.
'It just seems to work,' says consultant dermatologist, Dr Susan Mayou, of London's Cadogan Clinic. 'I've used it on patients of all ages and it's effective for a number of skin conditions, including psoriasis.' In a clinical trial in 2005, patients who suffered from itchy, rough dry skin were asked to use Aveeno lotion once a day for three weeks - nearly 90 per cent improved completely within that time.
Further studies have shown that an oat-based cream can be as effective as a prescription product on certain forms of skin irritation, and even on eczema. That might explain why, since 1981, Aveeno products have been included on the British National Formulary - the list of medicines that can be prescribed in the UK.
But according to Harley Street cosmetic dermatologist, Dr Sam Bunting, you don't have to have a skin condition to benefit from Aveeno. 'I love the products,' she says. 'They're affordable yet effective formulations that really help with dry skin, and I especially like the Aveeno Bath & Shower Oil. It's a luxurious and pleasurable product to wash with.'
A 300ml bottle of the Daily Moisturising Lotion usually sells for £7.65, the Bath & Shower Oil for £8.49 - although Superdrug is offering a third off Aveeno products and on Amazon they cost £4.66 and £5.42 respectively.
However, it's not all great news. One study suggested that repeatedly using creams containing oats on young children can result in them becoming allergic to oats.
And, in the U.S., devotees of 'green' beauty have objected to Aveeno's 'Active Naturals' tagline and the claim that the company 'uses only high- quality natural ingredients', citing the presence of petroleum-based compounds in its products.
But, according to Dr Mayou, if you want to go down the natural route and bathe in porridge, you're unlikely to get the same results.
'Oat baths are very messy,' she says. 'And they don't contain additional ingredients that these creams do - some have glycerine or ceramides which offer extra moisturising benefits.'