You ate a cupcake at the office birthday party (even though you swore you wouldn’t). You skipped the gym to go home and watch TV (can’t resist those Real Housewives!). And now you’re beating yourself up for it, right? We know, because we’ve all been there. It’s become far too common for us to mentally punish ourselves this way, thinking we’ll feel shamed into better behavior, observes Kristin Neff, PhD, associate professor of educational psychology at the University of Texas at Austin.But being our own worst Mean Girl is counterproductive. According to research in the burgeoning new field of self-compassion, a little TLC may go a lot further in motivating you to work out, lose weight, and get healthier overall. “Self-compassion means being kind to yourself, especially when you make a mistake,” explains Neff, author of Self-Compassion: Stop Beating Yourself Up and Leave Insecurity Behind. “As it turns out, caring about yourself is one of the best possible motivators for doing what’s healthy for you rather than what’s harmful to you.”As you’d expect, quitting the trash talk makes you feel good. In fact, brain-imaging scans done on Buddhist monks by University of Wisconsin neuroscientists suggest that self-compassion lessens anxiety and depression. But surprisingly, being kind to yourself also has a concrete effect on your behavior and physical well-being. “Studies show that self-compassionate people are more proactive about looking after themselves,” says Duke University professor of psychology and neuroscience Mark Leary, PhD, who’s been involved with much of the research in this field. “They’re more likely to take vitamins, practice safe sex, and go to the doctor when they’re sick.” Read on to see how you can score big health gains by giving yourself a break.Boost motivationMost people play drill sergeant with themselves: “I have to go to Spinning every day this week!” But using phrases like have to and setting too-strict goals are a recipe for falling short—and feeling lousy about it. In a study published in the journal Motivation and Emotion, participants who forgave themselves for failing at a task were more likely to pick themselves up and try again. “They didn’t let that one failure define them,” Neff says. “When you criticize yourself, you undermine your self-confidence, which is a huge part of motivation.”

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Try this: Encourage yourself the way you would a friend, with positive statements like: “If I go to Spinning, I’ll feel great, and I’ll probably fit into my jeans better, too.” Neff says: “Motivate yourself to do the right thing not because you’re inadequate, but because you want to be healthier, or land your dream job, or whatever your goal is. Keep your eyes on the prize, which is to be happy.” Lose weightA 2007 study shows how going easier on yourself can actually help you drop pounds: In it, Leary and a co-author asked two groups of women to eat doughnuts…

I’m guilty: I snooped around Jillian Michaels’ dressing room. I was left alone for a few minutes while she filmed part of her new show, Sweat Inc., and I spied something far too tempting to ignore: her stash of snacks.After all, the fitness entrepreneur, 41, is a powerhouse, and I wanted to know what fuel she’s putting in her machine. Her snacks include organic brown rice crackers; dry roasted, salted almonds; and root vegetable chips.And, boy, does Jillian need to keep her energy up. In addition to this show, which debuts on Spike TV this month, she’s shooting an E! channel docuseries, Just Jillian, that captures her life at work and at home with her partner, Heidi Rhoades, and their two kids, Lukensia, 5, and Phoenix, 3, set to air in January. She’s also busy writing a new book for mothers-to-be, Hot Mom, Healthy Baby, and has just launched a fresh-food line called Slim Soul (in select supermarkets). And that’s on top of the Impact fitness wear she created for Kmart. Jillian is still in full exercise garb because she’s just finished a workout on camera—but despite the name of her show, she isn’t breaking a sweat. “I take better care of my body now than I did at 20,” Jillian says as we walk across set to grab lunch. “I got kids. I’m like, ‘I need to be around for a while!'”RELATED: Where to Buy the Cool Clothes Jillian Michaels Is Wearing in Our October IssueBack in her dressing room, she sits cross-legged on the floor. Diving into salad and ravioli, Jillian shatters some myths about working out and offers seriously practical advice on leaning in to get the body and life we deserve.I notice you’re not eating any of the grilled chicken.I don’t eat a ton of meat. I have grass-fed beef once a week, and farmed shrimp and ocean-caught salmon, and sometimes some sole or tuna. I’m looking at the planet and really starting to see how our food policy and food practices are destroying the world. Even grass-fed beef is so bad for the planet. And we’re fishing out the oceans.Do you cook at home?We’re terrible cooks! Well, Heidi is a good cook, but she doesn’t have a ton of time. I am a terrible chef, so I hate to admit this, but one of the things we do is have a couple of restaurants that feed us—literally. The more I work out, the more carbs I need. I stopped eating sugar in December. Carbs, yes, but straight sugar, no.Is there one food rule you think we should all follow?I don’t believe in all or nothing. I think the key contents are: Don’t overeat, avoid chemicals as often as possible and…that’s it.RELATED: Transform Your Body in 4 Weeks With Jillian’s 7-Move Circuit WorkoutAnd of course people always want to know what one move is best for the whole body. Is there one move?People think there is a simple solution. Honestly, the majority of people with fitness phenomenons build a business by giving you a magic-bullet answer: “Eat whatever you want, except this, and you’ll lose weight.” “Eat whatever you want, but only during these hours.” “Just do one exercise…