What Is the Keto Diet and Should You Try It?

The high-fat diet can be beneficial for those who have obesity or diabetes
Eggs, avocado, bacon and cheese on a plate.

Over the past several years, you’ve probably heard a lot about the keto diet. While so many fad diets fade over time, the keto diet has continued to grow more popular. Some companies and restaurants even now offer “keto-friendly” options.

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But the keto diet, says registered dietitian Sharon Jaeger, RD, has more going on than a lot of other diets.

“It’s considered a medical, or therapeutic, diet,” she says. “This means that it’s extremely beneficial for people with certain conditions, but it’s not for everyone.”

Jaeger gives us a better idea about what the keto diet is, how it works and whether you should — or shouldn’t — consider giving it a try.

What is the keto diet?

“The keto diet is essentially a high-fat diet,” says Jaeger, “so your meals are 60% fat, about 30% protein and about 10% carbohydrate.”

For comparison, the average Western diet is 30% fat, 15% protein and 55% carbohydrate.

While the low-carb part of the keto diet may sound similar to the Atkins diet, a keto diet has a few differences.

First, the keto diet maintains a higher fat intake than Atkins. Second, while the Atkins diet has phases, the keto diet is a singular, consistent diet. And, third, the keto diet has the therapeutic element, whereas Atkins is primarily focused on weight loss.

How does it work?

The premise of the keto diet is pretty straightforward.

“The keto diet switches you from using glucose, which carbs provide, to using ketones, which fat produces, for energy,” explains Jaeger.

This switch — also called ketosis — can prompt these changes in your body:

  • Your metabolism speeds up.
  • Your hunger goes away.
  • Your muscle mass increases.
  • Your blood pressure and heart disease risk profile improve.

Over time, our bodies adapt to certain situations, like shifting from carbohydrate metabolism to fat metabolism when necessary, using fat as fuel for energy, also when necessary.

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“Eating fat doesn’t make your insulin go up, as eating carbs or protein does,” Jaeger points out. “So, the keto diet doesn’t spike your insulin, and you don’t store fat. Instead, you burn it, creating the ketones that give you an effective and efficient metabolic jolt.”

What foods can you eat?

Remember, the focus is on fats with a mix of protein but little in the way of carbs. This includes:

  • Meats, including high-quality red meat (steak and ham) turkey and chicken.
  • Eggs.
  • Avocados and avocado oil.
  • Other healthy oils, including extra virgin olive oil and coconut oil.
  • Fish like salmon, tuna and scallops.
  • Butter and cream.
  • Nuts like walnuts, flaxseed, pecans and chia seeds.
  • Vegetables that are low in carbs like broccoli, spinach, kale, tomatoes and cucumbers.
  • Unprocessed cheeses like cheddar, Gouda, Parmesan and goat cheese.

Alcohol, sugar and sugar drinks, beans and high-carb veggies like potatoes and carrots are out the window. You’ll even need to cut back on fruit due to the sugars they can carry.

But it’s essential you consult a healthcare provider first before trying this diet. Moving to a keto diet could mean big changes, and everyone’s needs are different. A doctor or a registered dietitian is best positioned to help you create the best diet plan to benefit you.

Is the keto diet healthy?

There’s still not enough long-term data to say that the keto diet is effective and safe over a long period of 20 to 30 years.

“But if you’re overweight or diabetic, this diet can help get your system out of metabolic crisis and put it in a healthier state,” Jaeger notes.

It’s important to eat real, whole, fresh foods when you’re on the keto diet.

“This includes nonstarchy vegetables,” Jaeger adds. “Frozen food is OK but shouldn’t be processed.”

So, whether you’re doing the keto diet, the Mediterranean diet or a low-fat diet, what matters most is the quality of the food you eat.

Who should try the keto diet?

The keto diet is the standard of care for treatment-resistant epilepsy.

While the exact science of what happens isn’t fully understood, the diet has been used for a century to help alleviate epileptic seizures, particularly in children. It’s believed that a combination of the high-fat and low-sugar content has an effect on how “excitable” the brain is and, thus, reduces seizures.

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But doctors are also seeing its benefits in other neurological conditions. The keto diet can be a powerful intervention, particularly for people with the following conditions:

  • Type 2 diabetes. One study found that being on the keto diet for one year reversed diabetes for up to 60% of participants. With an average weight loss of 30 pounds, they dramatically reduced or eliminated their need for insulin and no longer needed oral hypoglycemic drugs. The keto diet is also easier to sustain than other diets.
  • Class III obesity. If your body mass index (BMI) is over 40 — or if you have insulin resistance without Type 2 diabetes — the keto diet can be very helpful as well. It can be used as a short-term strategy to reset your metabolism and you don’t have to be on it forever.

Research suggests the keto diet might also help those with Alzheimer’s disease and autism.

“Again, it’s vital to work with a doctor or healthcare professional who can treat and follow you while you’re on the keto diet,” stresses Jaeger.

Who shouldn’t try the keto diet?

“Our responses to the keto diet are individualized,” she says. “They’re based on our biology, our metabolism, our numbers and the way we feel.”

Some people can sustain the diet for decades while others don’t fare as well.

Those who shouldn’t try the keto diet include those who:

  • Have an eating disorder.
  • Are at risk for heart disease.
  • Have kidney disease.
  • Are pregnant or trying to become pregnant.

The keto diet is generally only explored in children with epilepsy, Type 2 diabetes or obesity, too. 

How to get started on a keto diet plan

First and foremost, consult a healthcare provider. Not only can they help you outline a plan that works best for you, but they can also alert you to any unnecessary risks you might face with these changes to your diet.

If you’re given the all-clear to give keto a try, do plenty of research to see what foods fit and what foods don’t fit the plan. Then, consider meal-planning. This gives you an opportunity to make sure you’re getting a good variety of foods to get as many different nutrients as you can.

Planning your meals in advance also ensures you don’t overdo any one food, like red meat or other foods that can have a detrimental effect on your health in large amounts.

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