I’ve been wanting to write this post for a long time but have struggled to gather my thoughts. Now that I’m so fed up with this fad I finally decided to make my frustration productive by educating instead of screaming every time I hear someone say “I’m going keto” or see another “keto-friendly” menu offered by a restaurant.

I want to start off by saying that if you’re following a keto diet and it’s working for you and you’re happy – that’s awesome, you do you. I’m not here to tell you what to do, I’m here to empower you to make your own decisions and tell you what I know to be true, realistic, and scientific as a dietitian. You are allowed to make your own food choices based on what’s best for you and your health. However, just because the keto diet (or any diet for that matter) works for you, does not mean it’s going to work for everyone. Just because you eat or follow a specific diet DOES NOT make you qualified to counsel others on what to eat. Remember, if there was an eating style that worked for everyone, there would be no need for all of these crazy fad diets being thrown at us left and right.

Keto 101

“Keto” is short for “ketogenic.” The ketogenic diet has become wildly popular in recent years, but the truth is that it’s really nothing new. This diet has been used therapeutically for decades to treat epilepsy in children (there is evidence of it being used all the way back in the 1920s) . It has also been studied for its potential to hinder tumor growth in brain cancer patients, help with blood sugar control in type 2 diabetes, improve outcomes for certain neurological diseases, and the apparently most attractive effect – promoting weight loss. With that being said, there is no conclusive scientific evidence for it to be used as an intervention for prevention, treatment, or cure of any disease besides epilepsy. Most of the studies that have been conducted on the ketogenic diet have several limitations and therefore more research is needed to prove any of its health effects.

The goal of the ketogenic diet is to get the body into a state of ketosis, which is when the body starts using ketone bodies (ketones) for energy instead of carbohydrates, or glucose. Ketone bodies are produced from stored fat – they do not come from foods. They are the metabolic result of “starving” the body of its preferred energy source (glucose) and using fat for energy instead. In order to get into a state of ketosis, carbohydrates must be restricted in the diet (typically to less than 50g of carbohydrate per day – but this will vary from person to person). The “true” ketogenic diet is mostly made up of fat with moderate amounts of protein. When used clinically, ketogenic diet plans are generally focused on a 4:1 fat to carbohydrate ratio. In order to tell if your body is truly in ketosis, you have to undergo a blood or breath test, or pee on a stick (fun!).

What can you eat on a ketogenic diet? Mostly foods such as meat, eggs, nuts and seeds, oils, butter, cheese, fish, poultry, and some non-starchy vegetables. Fruit, grains, legumes, some dairy products, vegetables (starchy AND non-starchy) are very limited in ketogenic diets due to their carbohydrate content. Yes, this also means that cupcakes, ice cream, candy, bread, and beer are not allowed on the true ketogenic diet.

Now, let’s talk about the weight loss really quick. I won’t deny that people lose weight on the ketogenic diet. Lots of weight will fall off initially due to water loss from your body dumping its glycogen stores (glucose/carbohydrate/sugar that is stored in your muscles & organs). The weight loss might continue after the water weight drop, especially if you remain in a state of ketosis. Let’s take a step back, though, and think about some of the reasons why this weight loss occurs.

1) If you were eating lots of junk food, added sugar, and refined carbohydrates before and suddenly switch to a ketogenic diet that consists of mostly whole foods – of course you’re going to lose weight.

2) You will automatically eat fewer calories on the ketogenic diet because you are restricting food groups AND eating foods that are high in fat aka super filling. THE SAME THING will happen if you go on a low-fat diet, vegan diet, or simply a diet that includes more whole, nutrient dense, high-fiber foods and healthy fats. You can implement these sorts of changes into your eating pattern without following a fad diet or eliminating entire food groups.

OK – so the ketogenic diet leads to weight loss. What happens when you get totally sick of eating this way? What happens when you want birthday cake or pizza, or God forbid: a sandwich?!?! The second that you veer off the diet, the weight will start creeping back on. And therefore, I would not call that sustainable. Science doesn’t call it sustainable, either. As of right now, we only have studies that show short-term weight loss from the ketogenic diet but there are NONE that have proven the ketogenic diet to lead to long-term weight loss.

It’s also worth mentioning that many perfectly healthy & nutritious foods are restricted on the ketogenic diet (fruit, legumes, whole-grains, etc). Sure, you can still meet your nutrition needs on a ketogenic diet, although it will be quite challenging. Your fiber and antioxidant intake will likely fall short, which your body needs for proper digestion, heart health, and fighting infection.

One of the things that I dislike most about the ketogenic diet craze most is that people have begun to think that carbohydrates are inherently bad and that couldn’t be further from the truth. It’s a dietitian’s worst nightmare to hear anyone say “carbs are bad.” YOUR BODY NEEDS CARBS. You cannot function without them. Carbs provide energy. Carb-containing foods provide vital nutrients, fiber, and antioxidants that you cannot survive without. Sure, eating too many carbs (especially those that are refined like desserts and candy and soda) can damage your health and well-being. But so can eating too much fat and protein, yet no one seems to be worried about that when they jump on the ketogenic diet train.

The Bottom Line

Case in point, the ketogenic diet is just another fad, quick-fix, and marketing strategy. It may have some therapeutic benefits for some – and even in these cases, anyone following a ketogenic diet for therapeutic reasons must be monitored closely by a registered dietitian and physician to make sure the diet isn’t having any negative impacts on other aspects of their health AND to make sure they do not fall short in any key nutrients.

The ketogenic diet is not sustainable for most people to follow. Not only does it cut out entire food groups, it cuts out an entire macronutrient (carbs) that let’s be honest: most of us love and will have a really hard time restricting to the level that is required on a true ketogenic diet.

You want to eat more healthy fats? Great. Want to eat more protein and vegetables? Great. Want to eat fewer sweets? GREAT! You can do that without the ketogenic diet (and any other fad diet). You can do that RIGHT NOW without eliminating entire food groups or making a complete 180 with your eating habits.

The best diet is one that you can maintain for the long haul – one that keeps you healthy and feeling great, and also allows you to enjoy your life and live according to your values. Is the keto diet the answer for some people? Sure. But is it the answer for ALL people? Nope. Sorry, the answer never has been and never will be a quick-fix. This means it might take longer than you would like to lose weight, get healthy, and to establish habits that you can keep up with. Change doesn’t happen overnight and you don’t just suddenly come across the “answer” to weight loss or correcting a health problem. It’s a never-ending journey. Your life and interests and food preferences and goals will change for as long as you are alive and therefore, there will most likely never be an “answer.”

I want to end by emphasizing how incredibly important it is to SEEK OUT A PROFESSIONAL for answers if you’re curious about a diet. A registered dietitian can help you sort through the noise to figure out what’s truthful in all the messages we get thrown at us from the media every single day. Additionally, if you decide you want to go on a ketogenic diet, I would encourage you to meet with a registered dietitian. While most dietitians don’t recommend fad diets, it is our job to help you make sure your diet is nutritionally complete according to whatever eating plan you feel is best for your health.