Another day, another fad diet. There’s Atkins, South Beach, paleo, Whole30, Sugar Busters—too many to name.
These days the buzz seems to be about a weight-loss craze called the keto diet. But it’s hard to sift through the contradictory advice found online. Two pounds of bacon a day? That can’t be good for you.
To help separate fact from fiction, Health Beat spoke with Kirsten Vereecken, RD, CSP, a registered dietitian at Spectrum Health Helen DeVos Children’s Hospital.
What is the ketogenic diet?
The ketogenic diet was developed at the Mayo Clinic in 1924 as a way to treat epilepsy in children. Although it was effective at controlling seizures, the diet fell by the wayside when new anti-seizure medications came on the market in the following decades.
In recent years, the ketogenic diet has made a comeback, and medical teams are again using it as a therapy for kids with epilepsy whose seizures can’t be fully controlled by medications.
The goal of the keto diet is to put the patient into what’s called a state of ketosis through a food regimen that’s high in fat and ultra-low in carbohydrates, with moderate amounts of protein. In simple terms, Vereecken said, ketosis is a metabolic shift in which the body uses fat as the primary energy source rather than carbs.
“When we eat carbohydrates, the carbs are converted to glucose, and that’s our energy source. When we don’t have carbohydrates to do that, then our body burns fat,” she said.
The process starts in the liver, where fatty acids are converted into ketone bodies, or ketones. Elevated levels of ketones in the blood leads to ketosis, which can decrease the frequency of seizures—though experts still don’t know exactly how this works in the brain.
The important point, Vereecken said, is that the ketogenic diet relies on precise ratios of fat to protein and carbohydrates, so it requires a watchful medical eye.
“When we have a patient come in to the children’s hospital and they’re going to be started on a ketogenic diet, they are admitted so that we can monitor them closely,” she said. “We look at their electrolytes, their labs, we monitor the ketones in their urine.”
The whole medical team gets involved, including a dietitian and a neurologist, to help keep the patient in ketosis.
Because this diet is so restrictive and individualized, it isn’t a healthy option for the general population, Vereecken said.
“I wouldn’t recommend the ketogenic diet to an adult patient or a pediatric patient for weight loss.”
Though they might lose weight, she said, “I would just fear that they’d be missing out on too many essential nutrients.”
Top 5 things to know about the keto diet
1. A ketogenic diet isn’t just another low-carb, high-fat diet
There’s a lot of misinformation online about the ketogenic diet, Vereecken said. In popular culture, people think of a keto diet as a modified version of the Atkins diet, when in reality it’s more restrictive than even the induction phase of an Atkins plan.
Celebrities who throw around the term keto don’t help, she said.
Most of what passes for a keto diet is only keto-like, in that it replaces some of the carbs in a person’s diet with fat and protein. That’s not ketogenic in the clinical sense, which limits carbs to as few as 10 grams a day.
But whether a diet is truly ketogenic or not, Vereecken said, a low-carb, high-fat diet has more downsides than upsides.
2. A keto-like diet can deprive the body of essential nutrients
The downfall of a weight-loss plan that’s high in fats and low in carbs is that it may deprive the body of nutrients we need for brain and body health.
“Any time you’re removing a large macronutrient like carbohydrates, your body is going to be losing some of the essential nutrients that come from that food group,” Vereecken said.
“You’re not getting your B vitamins, you’re not getting vitamin C, you’re not getting fiber in your diet, and all these things are needed.” Eliminating carbs may also throw off your electrolytes, like sodium, potassium and magnesium.
Though many people label carbs as bad, not all carbohydrates are created equal. The key is to choose smarter carbs: sweet potatoes, steel-cut oats, quinoa and fruit rather than white pasta, white bread, white rice and pastries.
It’s true that cutting carbs often leads to fast weight loss, Vereecken said, but in the first week or two much of the loss is water weight, because our bodies store water with our carbs.
3. Just because keto is a high-fat diet doesn’t mean all fats are fair game
“People think, ‘Oh, this diet sounds great—I can eat bacon and I can eat cheese and I can still lose weight,’” Vereecken said. “And then they drop pounds quickly and it’s instant satisfaction, instant gratification.”
But a diet high in saturated fat increases the risk of heart disease and stroke.
Keto diet or no, the fats we should be eating are unsaturated fats, which can combat diabetes and lower the risk of heart disease and stroke. For healthy fats, look to olive oil, canola oil, walnuts, avocados and fish.
4. A keto diet can have negative side effects
Those who experiment with a keto-like diet may also experience some unpleasant side effects, Vereecken said, including constipation, leg cramps, loss of energy, mental fogginess and headaches.
All of these can result from a change in diet and deficiencies in vitamins, minerals or fiber.
5. The Mediterranean diet is a better option
Rather than a keto-like diet or other low-carb eating plans, Vereecken recommends the Mediterranean diet, which she said is much healthier over the long term—and much less restrictive.
This approach focuses on smart choices in all of the food groups, while paying attention to portion sizes.
“You need a lifestyle that’s going to work for you and to help achieve your goals, but in a healthy way,” Vereecken said.