Dr Perricone's 3 Day Diet is also known as the 'face lift diet' and has attracted fans such as Eva Mendes, Courtney Cox and Oprah Winfrey. Despite the A-list following you don't need to take yourself off to an expensive retreat or survive on lemon and water to try the plan for yourself. All the ingredients are available online at Ocado, from £80, and the plan can be found in full, for free, here at www.perriconemd.co.uk. One requirement however is that you must not only like salmon you probably need to love it. We say this because for three days you will be eating the equivalent of two salmon steaks at breakfast, lunch and dinner.

Salmon is rich in DMAE (a substance linked with skin firmness), antioxidants and essential fatty acids. By loading up on this, along with plenty of green vegetables, eggs, oatmeal and berries you have yourself a skin rejuvenating meal plan. Team ELLE put the diet to the test and noticed after the allotted time that skin was more dewy and appeared plumper. People commented on how ‘glowing’ we looked. The downside? We couldn’t look at a salmon steak for a long while after.

Not everyone is convinced, however. A 2007 study found that DMAE had a negative effect on fibroblasts (the part of the cell that produces collagen and elastin). On the flipside a 2005 study found that DMAE had an anti-inflammatory effect, which is definitely a good thing. Find out why inflammation is your skin's enemy here...

This diet is packed full of good-for-you foods and if you can stomach the high quantity of salmon then you’ll notice positive effects on your skin in the short term. Perfect pre-Christmas or when your skin needs a quick boost. However come the New Year a more long-term approach will be a much better bet.