Working out, eating right, and still not seeing the results you're after? Nothing can be more frustrating. But CrossFit competitor Christmas Abbott, author of The Badass Body Diet ($28), knows what could be the issue.

"The biggest mistake people make when trying to lose weight is they restrict themselves too much," says Christmas. And this means not only the Food choices people are making but also the amount they're eating. Christmas adds that when you deprive the body of food, it will go into starvation mode and store what food it does get as fat. But if the foods you are eating are all foods that you hate, Christmas warns that you "won't stick with the program, and the bigger picture of a lifestyle change is lost."

Your best bet is to try and find a happy medium between eating enough calories to keep you satiated, but enough to also create a calorie deficit to result in a pound or two lost a week. You can't live on kale alone, so be sure to include foods you love, and if they're not the healthiest, either find healthier ways to enjoy them - check out these lightened-up versions of your favorite comfort foods - or allow yourself just a small taste each day, say of chocolate, to satisfy your cravings. This way of eating will be much easier to maintain for a period of time, so you'll be more apt to stick with it and reach your goal.