- The keto diet is a popular weight-loss strategy that hopes to get dieters into a state of ketosis, in which their bodies burn fat as a primary fuel source instead of carbohydrates.
- Going keto is not easy: Dieters strictly limit all carbohydrates, cut many fruits and vegetables out entirely, and consume mostly fat.
- This strategy makes sense for some people, especially those with a few specific health conditions. But researchers who study human habits and dieting behavior say the plan is unsustainable for most people.
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If food is fuel, then adopting a ketogenic diet is akin to overhauling your body's gas tank.
Keto, as it's more often known, is an eating plan that coaxes your body to burn fat for energy rather than using up carbohydrates first, as is typical.
This metabolic state, called ketosis, is the same thing that happens when we are starving — the body burns fat stores to stay alive. Keto dieters trigger that fat-burning mode by cutting out almost all carbs from their meals. On a well-planned keto diet, people get 70 to 80% of their daily calories from fat and 20 to 25% from protein sources, saying goodbye to sugar.
Doctors recommend keto diets in certain circumstances: It's an established way to help control Type 2 diabetes, and the plan has been used to reduce instances of childhood epileptic seizures for nearly 100 years. Scientists even have some limited evidence that keto diets might help overweight people keep extra pounds off, though other studies reject the idea.
But for most people, a high-fat, low-carb keto diet can be really hard to maintain. Instead, habit experts recommend a different way to eat healthy: creating simple, sensible eating routines that are easy to follow and can become almost hardwired over time.
The keto diet is highly restrictive
Although the keto diet has become popular, doctors and nutritionists stress that no one should start a keto plan on their own. If you want to try it, it's best to consult your physician and work with a nutritionist to figure out the healthiest way to implement the high-fat plan. (It's especially important to avoid relying too heavily on proteins and meats, which can be dangerous for kidney health and lead to gout.)
Aside from the metabolic shift into a fat-burning state, the keto diet is hard to adjust to psychologically. If you're going keto, daily eating often becomes a math equation. Some fresh fruits and vegetables, for example, can be very high in carbs. Cauliflower and avocados are staples of the keto plan, but forget about carrots and apples — they're too naturally sugary (carb-loaded) to keep you in ketosis.
The keto diet can help people cut down on processed foods and eat less sugar, which are both positive changes. But keto dieters also miss out on some great anticancer foods that fight inflammation.
The regimented and restrictive nature of the diet is a downside that even some keto die-hards acknowledge.
"That's a big problem with keto, right? It's not simple to do it," the cardiologist Ethan Weiss, who lost 20 pounds on the keto diet and is now developing a ketosis breathalyzer test, previously told Business Insider. "You have to be able to figure out how to get the food. Unless you're cooking for yourself a lot, it can definitely be a challenge."
Strict diets are quickly abandoned
The physiology professor David Harper, who is studying how the keto diet might help cancer patients, believes going keto should be a long-term choice, not a fad to try willy-nilly.
"You need to be committed, and you need to really say, 'I've been on the wrong path for a long time, and I'm willing to give up a lot of these foods that I really love, that I'm emotionally attached to,'" he previously told Business Insider.
Unfortunately, psychologists say most people do not approach a new eating plan with that kind of commitment.
"When most people go on a diet, they're not trying to form new habits," Wendy Wood, a psychology professor who studies habit formation at the University of Southern California, recently told Business Insider. "They are getting themselves to eat in a very different way, and they do so with a lot of energy, and effort, and self-control, and willpower. So, at the end of, say, three weeks, they're just tired of it. They're over it! And we can almost predict how long people will stay on these fad diets."
Wood said part of the problem is that being "on a diet" like keto requires people to make a lot of extra decisions throughout their day about what they can and can't eat. That's not how most people prefer to go about their lives. Humans excel at autopilot: About 40% of what we do every day is habitual and thoughtless.
"If we constantly have to struggle and make ourselves figure out how to make something happen, we're just much less likely to do it," Wood said.
She added that restrictive diets could also be socially isolating — another deterrent.
"You can't just hang out with your friends anymore and go grab lunch somewhere or meet someone after work for a drink, because the food that is generally available to us doesn't fit that diet," Wood said.
You can eat healthy and be lazy at the same time
It's often said that nine out of 10 dieters will fail, but that statistic is largely unproven. Instead, an overwhelming body of scientific evidence suggests that the most successful diets are plans that encourage people to munch in moderation and avoid overeating.
A 2009 study published in the New England Journal of Medicine found that it doesn't really matter how much fat, protein, and carbohydrates dieters consume — any diet can be successful if it's healthy and easy to maintain. Nutritionists are increasingly rallying behind this more nuanced, personalized approach to eating: No single diet is right for everybody.
Wood offered a few research-backed ways to hack your body's autopilot system in order to develop better eating strategies.
"None of this is going to seem very powerful, but over time, it really does influence our behavior," she said.
First, she said, make it harder for yourself to access sweet treats and unhealthy foods. So, for example, if you work in an office where there always seems to be free cake, keep healthier stuff at your desk (or at least closer to you than the cake) and let your intrinsic laziness work to your advantage.
Another trick: make healthy choices the norm by training your body over time, rather than depending on willpower. In one study, Wood trained research subjects in her lab to choose carrots as a snack when they were hungry, reinforcing that carrot-picking behavior "hundreds of times." Once those people were accustomed to snacking on carrots, they continued to select them even when presented with M&Ms as an alternative.
"If you can form a habit to choose healthy foods to eat, then that habit perpetuates even when you are faced with unhealthy options," she said.
A third strategy applies to any eating plan you adhere to: prepare in advance. Business Insider recently asked two registered dietitians and nutritionists — Jason Ewoldt from the Mayo Clinic and Julia Zumpano at the Cleveland Clinic — what they eat on a typical workday. Both said they pack their own lunches and snacks at home, and both select food that's high in fiber and protein but low in sugar, such as nuts, cheese, and fresh veggies. (Harper said he also carries a stash of nuts around with him in case he gets peckish.)
Whatever you eat, it's important is to find a plan that makes you feel good and stick to it.
"Food is intensely emotional," Weiss said. "It's personal, and it's very easy to judge people based on what they do or don't do, and how different it is from what you do."
