Fad diets constantly rotate through the public opinion, often as reiterations of the same old promises for weight loss and health optimization. It was Atkins decades ago, then the paleo diet took hold, and now the ketogenic diet is common among the health conscious.

Keto promises weight loss and performance perks with its high-fat, low-carb breakdown. Followers of the diet attest that it will increase mental clarity, paradoxically protect against heart disease and possibly even protect against cancer — claims that appear to fall into the too-good-to-be-true category.

Keto may be new to the mainstream in the last several years, but the diet has an old history. The keto diet has been in use since the early 20th century — created by physicians in the 1920s in an attempt to control epileptic seizures.

It was used as a successful treatment, especially for epileptic children, for decades until the advent of anti-seizure medication. Once pharmacological measures proved more effective and well tolerated, the keto diet dropped from view. But in recent years, keto has exploded as the diet du jour with meal plans and recipes that are only a click away.

Traditionally, your carbohydrate intake should be anywhere from 50 to 60 per cent of your total diet, with fats being around 30 per cent. Keto, on the other hand, shifts this balance dramatically, recommending that up to 75 per cent of your dietary intake be fat-based with less than 10 per cent being made up of carbs.

Fat makes you full: a meal high in fat puts the breaks on your gut mobility — slowing down your digestion and making you feel satisfied for longer periods. This, obviously, is the biggest contributor to the weight loss experienced on high-fat diets.

As expected, a dramatic change like this will have huge repercussions on your body’s normal functioning. The whole point of the keto diet is to change the way your body uses molecules for fuel. Generally, our bodies run on glucose — the sugar we get from all those delicious carb-loaded meals — but on a keto diet, your body is forced to use its fat stores for fuel.

By breaking down fat into its smaller parts, known as fatty acids, molecules called  ketone bodies are extracted and used for the body’s energy needs.

Keto diet practitioners want to achieve ketosis, and users will purchase test strips to test for the presence of ketone bodies in their urine. These are preventative monitoring tools used by diabetics to avoid ketosis and a serious illness called ketoacidosis, that occurs because people with type 1 diabetes are unable to utilize glucose.

Just to put things into perspective, keto diet followers are trying their very hardest to reach a state that diabetics try their very hardest to avoid.

While the chance of individuals without diabetes reaching these dangerous levels of ketones is small, it is not unheard of. A case study from 2006 reported the hospitalization of a non-diabetic woman for ketoacidosis after an extremely low-carb diet. But luckily, for the majority of healthy adults, achieving and maintaining ketosis is very difficult.

Even if you are following the diet closely and your test strip reads a nice lavender colour, you are likely to drop in and out of ketosis because your body just doesn’t want to be there.

One of the most troubling messages to come out of this diet is that of cancer prevention and treatment. Insulin has a complex role in cancer — it can cause cells to keep growing and dividing, which can be problematic.

Studies have found that suppressing insulin, something keto does, is beneficial for cancer treatments. Cancer researcher and author Siddhartha Mukherjee found that the insulin suppression of keto diets can also enhance the positive effects of a cancer-fighting drug called a PI3K inhibitor.

However, there was a catch. Mukherjee warned users on Twitter that people should not switch to a keto diet without a PI3K inhibitor or medical supervision, emphasizing that his investigations had discovered that the progress of leukemia was actually accelerated by a keto diet alone.

Diets — especially those with extreme restrictions — can be dangerous. They can lead to disordered eating and dietary deficiencies. They are also the hardest diets to maintain. Eating healthy is complex, and it’s easy to fall into diet traps that promise incredible results. Make sure you know what you are getting into before you jump on the fad-diet bandwagon.

—

Erin Matthews / Opinions Editor

Graphic: Cree Longjohn