The premise behind the Ketogenic Diet, commonly known as the Keto Diet, is essentially to mimic starvation.

Glucose, mainly produced by carbohydrates, is our body’s preferred source of energy. When there is not enough glucose available (like during starvation), most of our body tissues can use fat and protein for fuel instead. Our brain, however, has a more difficult time adapting. For our brain to continue functioning effectively, it needs an alternative energy source. So, our body starts to break down stored fat to produce chemical compounds called ketones, which our brain can use for fuel. This process is called ketosis.

The goal of the Keto Diet is to get the body into this starvation mode (ketosis) so that it breaks down stored fat, resulting in fat reduction and weight loss. It sounds simple enough, but there are some red flags to consider. 

The diet itself is high fat, moderate protein and low carbohydrate and can be very challenging to stick to because it is so restrictive. It isn’t possible to kind of follow the keto diet because if you consume more than the recommended amount of carbohydrate, your body will switch back to using glucose as its main energy source, therefore defeating the purpose of the diet all together.

It’s going to be next to impossible to lose weight on a high fat diet if your body isn’t breaking down stored fat!  Because protein can also produce some glucose, the same can be said for eating more than the allotted amount of protein.

Regardless, you will simply be eating a high fat, low fibre diet, which comes with common side effects of constipation, fatigue and brain fog and puts you at risk for nutritional deficiencies, disordered eating and health conditions such as heart disease and diabetes.

It’s also important to consider that, if not followed correctly, this diet can be dangerous. There is a risk that the body could produce excessive amounts of ketones, leading to a condition called ketoacidosis which can cause damage to body tissues and in extreme cases can result in coma or death.

Similarly, it can be harmful for the body to be rapidly pulled out of active ketosis. Meaning, if you have followed the diet correctly and your body is actively using ketones for fuel and then you suddenly have a “cheat day” and eat a bunch of carbohydrates, there could be serious consequences as your body tries to quickly adapt to the sudden influx of glucose.

The Keto Diet is really an all or nothing diet. 

Speaking specifically to weight loss, the Keto Diet is meant to be used short-term as research has shown harmful effects when used long-term (such as decreased bone density and muscle loss). Which means, if used correctly (ideally under the guidance of a professional for safety purposes) for a short period of time, it can be an effective tool for kick starting lifestyle changes and weight loss. But the weight loss is challenging to sustain long-term and can result in more weight gain once the Keto Diet is no longer being followed. 

There are a lot of trendy diets out there that come with the promise of quick results. They’re advertised as simple tools you can use to take control of your health, feel better and look better. But it is important to remember that all these diets come with their own list of safety concerns, potential harmful long-term consequences, and sustainability issues.

Certainly, these extreme diets can be effective in some specific circumstances when followed correctly. But for most of the population, they simply don’t work and often cause more harm than good.

Amanda Turner has been a Registered Dietitian since 2016. She has experience in several practice areas and is the owner of Navigate Your Plate Nutrition Services.