'Tis the season for overcrowded gyms and people following all manner of diets. One of the buzziest right now is a diet that's been used for years to treat certain medical conditions, but is now a trendy weight loss plan touted by celebs (and maybe the mom on the treadmill beside you).
The Ketogenic Diet (Keto Diet for short) is a very high-fat, very low-carb diet. The idea is that when you deprive your body of its preferred fuel source (carbohydrates), it uses fat for energy instead. This causes the body to produce something called ketones, which are chemicals made by your liver that can be used by cells for energy. When you're in that state, it's called being in ketosis. On the Keto Diet, you eat lots of meat, veggies, high-fat dairy like cream and butter, nuts, and coconut oil but no grains, fruit, potatoes, beans, or sugar.
Will you lose weight? Probably. The body uses a lot of calories turning fat into energy, and eating lots of veggies and high-fat foods can be very filling, so your appetite may become dulled.
But there's also a good chance you may be miserable. "The main issue with Keto is that it's extremely difficult to stick to," says registered dietitian Abby Langer. Since weight loss depends on staying in ketosis, it's not something you can go off and on without gaining back any lost weight.
It's also not a lifestyle that's easy for most people. "If you love food, if you love to go out and socialize, those things are going to be difficult for you," says Langer. She cautions that it may be especially difficult for moms. "Most of the moms I know feel controlled to some degree by motherhood. Are you okay with being controlled with your diet, too? Not being able to eat a lot of the foods you might love, like fruit, a cocktail, the occasional cookie, or bread? Ever?" says Langer. "Is it going to be a challenge or awkward to prepare your own dinner every night while your family enjoys something less restrictive? Say goodbye to family pizza nights! Motherhood is tough, I'm not sure I'd recommend making your life tougher with such a restrictive diet."
Whether or not it's completely safe either is still a question. Side effects range from constipation due to lack of fiber and low blood sugar (which can lead to dizziness and weakness) to kidney stones, since burning fat for energy can be hard on the kidneys. The jury's also out on the long-term health effects of eating so much fat, especially saturated fat, Langer adds. Though the Keto Diet has been used for years to treat some medical conditions like epilepsy, it may not be safe with other conditions such as diabetes.
What's more, modeling restrictive diets of any kind with your kids isn't wise. "It's important to consider the example you're setting for your children by cutting groups of healthy foods out of your diet," she says. "Watching mommy diet isn't a healthy way for kids to learn about eating and body image. Many of my clients have their own eating issues now because their parents were constantly dieting, and this affected kids' perceptions of their own bodies and their attitudes towards food and eating."
And what about the pro-Keto websites that say your kids can safely join you on the diet—is the Keto diet safe for kids if they don't have a medical condition that requires it? "No," says Langer. "I never agree to children being on diets, and growing bodies need carbohydrates and proteins. Their growth and development can be profoundly affected by this diet and others. No, no, no."
Read more of Langer's thoughts about today's trendy diets, including Whole 30 and 21 Day Fix.
Sally Kuzemchak, MS, RD, is a registered dietitian, educator, and mom of two who blogs at Real Mom Nutrition. She is the author of The Snacktivist's Handbook: How to Change the Junk Food Snack Culture at School, in Sports, and at Camp—and Raise Healthier Snackers at Home. She also collaborated with Cooking Light on Dinnertime Survival Guide, a cookbook for busy families. You can follow her on Facebook, Twitter, Pinterest, and Instagram. In her spare time, she loads and unloads the dishwasher. Then loads it again.