The diet, devised by nutritionist Angela Dowden, encourages followers to eat 5 times and get their five fruit and veg a day - and claims that you can drop 5lbs in the first two weeks of following the plan.
'The science behind our 5:5:5 is very simple – it's about eating more (at least 5 portions daily) of healthy fruit and veg - particularly high fibre, low cal greens– that fill you up and help keep you trim,' Angela explains. 'It's also about having regularly spaced meals and snacks every day to keep hunger at bay. These healthy eating principles help lower risk of heart disease and cancer and boost energy levels too!'
Eating little and often has long been championed as a method for keeping struggling dieters on track. In April 2015, Jennifer Aniston's 'better living expert' Kathy Kaehler revealed that the actress aims to eat 'five small but nutritious meals' each day, based around protein rich ingredients like eggs, fish and chia, whilst a study published in the American Journal of Clinical Nutrition showed that women who eat erratically consume more calories and burn them off slower than those who have six regular small meals a day.
The 5:5:5 diet takes these principles and applies them in a way that has been dubbed the 'easiest and healthiest' way to lose weight. So we know you can eat five times per day - but what is it that you should be eating at those times?
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A typical day on the 5:5:5 diet could include blueberries and a sliced kiwifruit with fat free yoghurt for breakfast, poached salmon fillet with salad and tzatziki for lunch, and a lean lamb chop with vegetables served with cous cous for dinner.
You can then fill in the gaps between meals with snacks, like a banana or a handful of nuts and raisins - although you're advised to avoid snacking too close to mealtimes, and ensure that your portion sizes are modest.
You'll also need to cut out sugary drinks and snacks, and check the labels of the products you are buying for hidden sugars and fats too. It's important to note that anything containing over 22g of sugar or 5g saturated fat per 100g should be avoided - but unlike many popular diet plans, there's no need to count calories.