Celebrity trainer Matt Roberts recommends you aim for 30 minutes of exercise each morning. Most people think they're too busy to fit in a gym session, so that could mean cycling to work, running through the park or walking fast until you're out of breath. Then feel smug for the rest of the day. Result!
Fill up first thing
Don't be tempted to skip breakfast – Jennifer Lopez, Jessica Alba and Cameron Diaz all start the day with an energy-boosting meal. And they don't look half bad. If you don't want to load up with too many calories in the morning, try egg whites on wholemeal toast.
Eat more, burn fat
Oh yes. Some foods actually have "negative" calories, which means you use more energy digesting them than you take in by eating them. Unfortunately, profiteroles aren't on that list, but broccoli, carrots, apples, satsumas and strawberries are. Woop!
Don't starve yourself
Crash dieting only works for a while – once you start eating normally again, the weight will pile back on. Keep cravings at bay and eat healthily with a low GI diet instead, which is all about eating food that releases energy slowly. Try porridge for breakfast, a chicken or fish sandwich on wholegrain bread for lunch and vegetable soup with wholeweat pasta for dinner.
Ditch the boring workout
Tracy Anderson, trainer to Madonna, Shakira and Gwyneth Paltrow, recommends changing your workout every ten days to keep things interesting. So don't stick to the same old lunchtime in the gym routine – switch from running to swimming to weights to pilates and keep your body challenged.
Go "Clean and Lean" for a week
Rosie Huntington-Whiteley, Elle Macpherson and newly-slim Nigella Lawson have all followed James Duigan’s Clean & Lean diet plan and ditched processed food, sugary snacks and junk. That doesn’t mean they’ve gone hungry though – they eat natural, stress-reducing food instead.
Try a handful of berries with breakfast, dark green vegetables with every meal and swap fatty meat for lean, skinless turkey. If you're craving carbs, go for sweet potatoes and snack on avocado and a handful of nuts. And you can still have one or two cups of coffee a day too.
Detox to suit you
No, that doesn’t mean surviving on freaky fruit juice and fainting by midday! Make a list of all the little things you eat and drink that you know are bad for you, but that you could cut out without starving yourself, then ditch them from your diet for a week. That could include mayonnaise, butter, crisps, chips, wine, an extra sugar, a full fat latte, or that 4pm chocolate bar you always have because you're bored at work.
Give them up for seven days and see how much weight you lose. Chances are, when you see how hot your booty looks, you won't be craving them anymore!
Cut out white foods
Celebrities often use this diet trick as a quick fix before a red carpet event. Cameron Diaz's trainer Teddy Bass recommends avoiding bread, pasta, biscuits and rice if you're trying to lose weight fast, as they're all high in sugar.
Work your muscles hard
At the beginning of your workout, your muscles aren’t exhausted so spend less time resting them – 20 to 30 seconds will do. But as you get tired, try a rest of 40 to 60 seconds between exercises. Celebrity trainer Joe Dowdell, who’s worked with Claire Danes and Anne Hathaway, recommends this technique to force your muscles to work harder and improve your endurance.
Don’t give up
Just because you've had a bad day with your diet doesn’t mean that it’s game over. Get back on the horse. If you're finding it difficult to stick to a diet, follow celebs like Katy Perry and have one day off a week. Phew - even K-Pez relaxes her regime on a Sunday for a good burger.