Keto diet Q&A: Holy grail of health? Or fitness fad?

photo illustration Gabriela Faraone

The ketogenic diet holds a certain regard in the health and fitness industry. It promises weight loss, a healthier life and better performance. But how sure are we that it is healthy for us to follow?

We talked to instructor Kathleen Hoss-Cruz of Kansas State’s Department of Food, Nutrition, Dietetics and Health to learn more about this diet and its consequences for long-term health.

Gabriela Faraone, culture writer: “Can you tell us what a ketogenic diet is? If someone says that they are following this diet, to what are they referring to?”

Hoss-Cruz: “A ketogenic diet actually has quite a long history. It has been used to prevent seizures in epileptic children, and it is actually almost as effective as medication to preventing them.

“It’s an extremely high fat diet, where most of your daily calories come from fat. When your body is forced to rely on fat, it produces a chemical called ketones from fatty acid breakdown.

“In general, there are certain parts of your body like your brain, your nervous system and your blood cells that really only like to use glucose and can’t use fat. In fact, there is a barrier in between your blood and brain and the fat cannot cross that.

“A low carbohydrate diet in general has been advocated for weight loss for some time, and this is just some incarnation of that. It sort of is a replacement of the paleo diet, another current fad diet nowadays.”

Faraone: “If someone is thinking about following this diet, would you recommend it?”

Hoss-Cruz: “I would strongly encourage people not to pick a fad diet in general, no matter what it is. The best and most permanent changes are the ones that are slow and gradual.

“Strict diets like that are very hard to follow for any length of time. Especially the keto diet, when carbohydrates form 50 to 60 percent of our total daily intake. When you are taking this range down almost to nothing, it is going to be very difficult to maintain.

“My other big concern about the keto diet is that cutting out all carbohydrates means cutting out healthy foods like whole grains, beans, peas and most fruits and starchy vegetables.

“All of those foods are incredible valuable for our health and may provide phytochemicals that we don’t even know about. Fiber is incredibly important as well.”

Faraone: “What are some other health consequences to following this diet?”

Hoss-Cruz: “We are just now starting to develop an understanding on how important to our gut bacteria is. But we do know that gut bacteria helps us and they do not like high protein low fiber diets. They like carbohydrates, fiber, fruits, vegetables, greens and beans.

“But yes, you might lose weight on a ketogenic diet, but at the same time you are actually messing up with your health in general. Increasing your saturated fat intake is going to affect your health in the future. You are going to miss out on a lot of important nutrients that you need for your diet. Plus it’s not a sustainable diet to follow.”

Faraone: “To have an idea and general knowledge on how a healthy diet should look like, what macronutrient ratio it is recommended to a person to keep a sustainable and healthy lifestyle?”

Hoss-Cruz: “I would recommend them to follow the acceptable macronutrient range that is from the Dietary Guidelines for Americans and the Dietary Reference Intake. [It consists of] up to 60 percent of your total calories from carbohydrates, up to 30 percent of your total calories from fat and the rest is for protein. In fact, protein forms the smallest percent of calories in your diet.

“Your ratios really depend on what decisions you are making. If your diet is mainly based on steak, that is high in fat. You can pick other protein sources like beans, seeds, nuts and leaner meats that are going to promote your health over really fatty meals.

“With fats, it is the same story. Solid fats are known to increase your risk of heart disease, while liquid fats like oils on the other hand are known to reduce your risk of heart disease.

“Mostly the oils that come from plants or from fatty fish like salmon and tuna are good fats. For carbohydrates, as much as possible stick with fruits and vegetables. Whole grains, beans and peas are a good combination of carbs, fiber and protein.”

Faraone: “Nowadays we have this concept that ‘fat doesn’t make you fat.’ What do you think about this phrase that we are often hearing from the media?”

Hoss-Cruz: “The original health message that all health professionals are trying to send is that not all fats are bad for you. [Health professionals] were wrong to tell people to lower their fats in their diet because olive oil, vegetable oils and fatty fish are very important for health.

“But people like to have black and white answers to a very complex problem, when there are no black and white answers to these issues.

“Fat in moderation adds a lot to your diet like satiety, taste and flavor. It has a very important role, but there is nothing in our diet that we can go crazy on and not worry about. So I think that we just want to hear what we want to hear, and that was not what that message was.”

Faraone: “So why are all these fad diets popular in our society? What do you think is causing us to decide and follow these kinds of diets instead of just having a balanced and healthy diet?”

Hoss-Cruz: “The superior communication that we have like social media is very powerful and rapid. It outpaces our ability to judge the reliability of the information.

“People are not necessarily critical consumers of information. If it sounds good or it’s making a point on your thoughts you are more likely to believe it whether or not the information is reliable. One point that I really tried to point out in my class [basic nutrition] is how to judge reliable to non-reliable sources of nutritional Information.

“Another part is that we are facing an obesity crisis. We are eating too much and there is a consequence for that, and people are looking for easy solutions for their problems.

“Unfortunately, it’s not that simple. There is no magic pill, there is no magic diet, there is no magic food or activity. It is more about having a healthy relationship with food and treating your body well, and getting to know your food.”

Faraone: “One last question before we finish, what resources would you recommend to people to get reliable information about nutrition?”

Hoss-Cruz: “If they want to know about specific types of diets, they should check

“For more common, trending topics on nutrition, the Harvard School of Public Health newsletter and blog. If you want to just more of a general information of nutrition, you can go to and also They have a lot of really good advice depending on your needs are to keep a healthy lifestyle.”

Faraone: “Great, thanks for all that information. Dr. Hoss-Cruz, a short message for our readers?”

Hoss-Cruz: “I am going to quote Michael Pollan here. I don’t necessarily agree with all his book, but I do like this statement. Pollan says ‘Eat food, not too much, mostly plants.'”