The holidays are coming upon us. It's time to look for a fad diet that will get us in that skimpy dress fast.

Celebrities are masters at this though -- getting red carpet ready in a few weeks. So, let's get their secrets out!

Sirtfood Diet

Adele debuted her 20-pound weight loss at Drake's birthday and wow, she totally killed it! So how did the British singer say "Hello" to a fitter physique?

The diet is pretty healthy with low-cal foods, lots of protein  and green juices. However, it's not all pain and deprivation here. You get to indulge in red wine and dark chocolate some days. Pretty good trade-off, right?

2-Ingredient Diet

The unofficial Christmas diva Mariah Carey takes strict diet regulations to a whole new level. She is pretty consistent with her meal choices -- just Norwegian salmon and capers each and every day.

The diet is not so bad because salmon has omega-3 fatty acids that should keep you energized and capers balance those fats. What we love most about Carey's diet is the great skin benefits in the end.

Dukan Diet

Duchess Kate Middleton stays in shape with the French-based diet that is great for those who gets bored on their regimens easily.

Dukan has four phases to help you meet your fitness goals: The Attack Phase kick starts your metabolism with the most satisfying weight loss, which great to make the most of your motivation while it is there.

So the Attack Phase is more on low-fat and high-fiber. Next is the more gradual weight loss with the Cruise Phase, where no fruits and starchy vegetables like carrots and sweet potatoes are allowed.

Guiding you through a more long-term plan are the Consolidation and Stabilization Phases -- zero weight loss here but it makes sure you don't bounce back.

5-Factor Diet

Katy Perry is getting ready to marry actor Orlando Bloom, so there is more pressure for her now to slip into the wedding gown of her dreams yet again.

The diet was created by celebrity trainer Harley Pasternak. It is reportedly a craze in the music industry, with the likes of Lady Gaga and Alicia Keys going on the diet as well.

There are five key components to the diet, which includes carbs, fat, fiber, protein and fluids. It's a well-rounded diet and you get to eat five meals a day. However, the recipes you eat should contain no more than five ingredients.

Five Hands Diet

Think the five factor is easy? Try Victoria Beckham's diet.

Post-pregnancy, Victoria shrunk back to her pre-baby weight fast by taking diet to an extreme. Eat like Beckham if you dare: only five handfuls of food a day.

Better have big hands!

Sensa

Sprinkle some of this magic ingredient on your food and it will curb your cravings, sound interesting? It does to "Millionaire Matchmaker" star Patti Stanger.

Stanger reportedly sprinkles the diet aid on chocolate gummy bears and other food weaknesses.

"I went to a size 4 from a size 6 in a little over 2 weeks with Sensa," Stanger revealed.

READ MORE: Kim Kardashian Laments 18-Pounds Weight Gain