Burning Fat With the Keto Diet — Is It Safe or Not?

March 8, 2019 Updated: March 11, 2019

If you want to lose weight, you are not alone. More than two-thirds of Americans are overweight and a third of them are obese. The problem is many people (an estimated 85%) do not succeed with their weight loss plans. So what is an effective diet that can really help losing weight?

There are many types of weight loss methods out there, and the ketogenic diet (often called the keto diet) has gained popularity in the last two years. Some claimed it worked for them, but others like celebrity fitness trainer Jillian Michaels have criticized it.

Let’s examine the science, the facts, and the risks to let you decide if the keto diet is the right diet method for you.

What Is the Keto Diet?

Keto diet foods
Keto diet foods (SewCream/Shutterstock)

The Keto diet is a low-carb diet that focuses on fat. It’s different from other low-carb diets like Paleo, South Beach, and the Atkins diets, which focuses on high-protein foods. Keto dieters mostly eat high-fat foods like eggs, meat, oils, butter, cheese, and fish as well as very low-carb vegetables like leafy greens and cauliflower.

How Does It Work?

Ketosis
Ketosis (BK_graphic/Shutterstock)

In order to make the keto diet work, you need to restrict your carbohydrate intake to less than 50 grams per day. When you eat less than 50 grams of carbs a day, your body eventually runs out of fuel (in the form of blood sugar, which is broken down from carbs) and this typically takes 3 to 4 days.

After running out of blood sugar, the liver will start producing ketones from fat, and your body now enters into a metabolic state of “ketosis.” Ketones are produced if you eat very few carbs and will be used as an energy source for the body.

At the same time, you can only have moderate amounts of protein, because excess protein can also be converted to blood sugar. The recommended amount of protein is 60 grams a day if you are on the keto diet.

What to Eat on the Keto Diet?

The most important thing for reaching ketosis is to avoid eating too many carbs, keeping your carb intake under 50 grams per day or ideally below 20 grams. Also, only moderate amounts of protein, or around 60 grams per day.

Keto diet food
Keto diet food (Romawka/Shutterstock)

These are the real low-carb foods, like meat, fish, eggs, low-carb vegetables (eg. leafy greens) and natural fats like butter or olive oil.

You can also drink water, coffee and tea.

Foods To Avoid on the Keto Diet

Ketogenic diet food, banner with low carb high healthy fats. Vector illustration
Illustration (Danceyourlife/Shutterstock)

Here are some of the foods you should not eat on a keto diet – foods full of sugar and starch. As you can see, these foods are much higher in carbs.

You can read here for a full list of foods to eat and to avoid.

Does It Work?

Some keto dieters say it has transformed their lives.

Kristina said on her Instagram “I used to be severely overweight for a period of my life (probably considered obese).”

She said she tried everything but nothing worked. “It wasn’t until October of 2016 that I learned about the ketogenic lifestyle and started that way of eating and was able to lose 10 pounds in 2 months, just from making better food choices.”

She then began a fitness regime, and within one year she hit her goal. From June 2015 to January 2018, she lost about 76 pounds and 7 dress sizes.

View this post on Instagram

#TRANSFORMATION STORY PLEASE READ: I used to be severely overweight for a period of my life (probably considered obese). Some people have known me a long time and have seen my #progress, but some only know me now and don't know what I used to be. There are a few years of my life with zero to very few pictures of me because I hated the way I looked. After getting out of a toxic relationship (when I ate my feelings out of depression), I was able to lose a little bit on my own by focusing on #me and getting back into activities I loved (musical theater) and overall being happy again. But I was still overweight and sort of hit a plateau, so I gave up on trying because nothing seemed to be working. It wasn't until October of 2016 that I learned about the #ketogenic lifestyle and started that way of eating and was able to lose 10 pounds in 2 months, just from making better food choices. In January of 2017, I began a fitness regime, going to the #gym about 4-5 days a week doing a mix of weight lifting and cardio. My plan was to hit my #goal weight within one year. (To be honest, I didn't think I was going to do it, but told myself I'd be happy if I got close.) It's been one year since I did my first #workout on my own and I am so excited to say that I did it…I HIT MY GOAL WEIGHT!!! From June 2015 to now, I have lost about 76 pounds/7 dress sizes and I'm a happier, healthier, and stronger version of myself than I ever was before! It's not just about the number and how I look, but I've learned that I need to take care of my body from the inside out for #health reasons too. I now have more energy and I feel absolutely amazing. I finally feel like the version of myself that I always envisioned in my head. This has been a long and hard #journey and there were many times I thought I might give up. I'm sharing these pictures not out of vanity, but because I'm just so #happy that I did it and I want people to know that you can do whatever you set your mind to!! 💪🏼💪🏼💪🏼 #follow

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Another testimonial is from Jay Albright, whose story was shared on Women’s Health. He lost 50 pounds and counting after one year.

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O n e Y e a r : Thankful for the Gospel and it’s power to transform all areas of life. Only God’s grace allows me to look back one year ago (almost to the day) to reflect on how far He’s actually brought me and my family. Lots of “negative” circumstances took place over the course of the last year, but the perspective of the guy on the left is VASTLY different from the guy on the right. I truly believe there are no negative circumstances in this life, only misunderstandings of what’s actually good (dare I say, “best”) for us. Keep pressing on, keep pursuing, keep searching for the only One worth anchoring your hope to. | #wonthedoit #godisgoodallthetime #stewardshipoflife #identity #hope #fattofitjourney #50lbsandcounting #Keto

A post shared by Jay Albright (@jayalbright) on


Are There Any Risks?

The ketogenic diet initially became popular as a therapy for epilepsy in the 1920s and 30s. Only in recent years has it been used for losing weight. While some people have success with the keto diet, it’s still controversial regarding its potential risks to people’s health.

In a Harvard Health article, Kathy McManus, who is the director of the Department of Nutrition at Harvard-affiliated Brigham and Women’s Hospital, noted that the keto diet is a medical diet and explained its potential health risks.

“The keto diet is primarily used to help reduce the frequency of epileptic seizures in children. While it also has been tried for weight loss, only short-term results have been studied, and the results have been mixed. We don’t know if it works in the long term, nor whether it’s safe,” said McManus who is a registered dietitian.

“If you’re not eating a wide variety of vegetables, fruits, and grains, you may be at risk for deficiencies in micronutrients, including selenium, magnesium, phosphorus, and vitamins B and C,” McManus added.

She said that too much saturated fat is linked to heart disease. Other problems include making existing liver problems worse, because the liver needs to metabolize so much fat. Kidney problems can also occur.

Furthermore, due to the fact that the diet is low in fibrous foods like beans and grains, some dieters may suffer from constipation.

Everyone’s body and health condition are different, so it’s highly recommended that you talk to a doctor before attempting a ketogenic diet to make sure it is safe for your health.

Disclaimer: This article is for informational purposes only and is not a substitute for professional medical advice.

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