Dr. Alexandra MacKillop

I was at the grocery store recently and saw a familiar brand of nut butter with a new label that read “Keto Friendly.” I almost burst out laughing. It was the same old nut butter blend, but in a new cultural context — one in which avoiding carbs is a mainstream practice, and in which brands can have a leg up with their marketing by using trendy buzz words.

Low carb diets aren’t new. Even just 30 years ago, the Atkins diet was wildly popular, claiming that a carb-controlled lifestyle offers everything from guaranteed weight loss to disease management and prevention. Then the ebb and flow of the diet cycle progressed to fear of red meat, hailing veganism as the cure-all, followed by the “superfood” craze (among others) and then finally circling back to low-carb.

Keto advocates would argue that the diet involves much more than avoiding carbs, such as an emphasis on including fatty acids, especially medium chain triglycerides, and keeping protein at a “moderate” level. But there isn’t anything moderate about the Keto diet. It’s an extreme approach to eating that can have extreme, negative consequences. Even aside from the profound psychological toll that such restrictive diets have on a person’s life, (leading to everything from anxiety to social isolation, to eating disorders,) the Keto diet creates a biochemical, physiologic disturbance in a person’s internal environment that is often overlooked by the radical ‘transformation stories’ on social media. Our society’s failure to recognize the Keto diet for what it is — a risky fad — is a public health problem.

A Recap of Functional Medicine

I define functional medicine as a framework in healthcare that looks at the big picture of a patient’s life. This means evaluating symptoms in light of everything else going on, like nutrition, lifestyle, environmental exposures, and stress levels, all of which profoundly affect our health. Treatments in functional medicine focus first on supporting the body’s internal environment with non-invasive methods like nutrition, lifestyle, and supplementation so that drugs and surgery can be avoided as much as possible. The long term goal is to restore the patient’s body to its normal, natural, healthy state that is self-regulated without the need for much intervention at all. [Read more about functional medicine here.]

The sentence in bold represents the primary problem that I see with the Keto diet. Other critics represent risks such as vitamin deficiencies, but those can be corrected (or prevented, when monitored properly.) Others warn against the risk of inflammation, chronic health problems, bone loss, kidney stones, and even infertility. But these latter concerns can all be grouped together under the umbrella statement that the ketogenic diet forces a person’s body into an abnormal chemical state that it was never meant to sustain.

What is Ketosis?

The center of human metabolism is glucose, which is a type of sugar. Almost every cell in the body was designed to use glucose as fuel, which it breaks down through a series of chemical reactions into energy (in the form of ATP) and waste products (carbon dioxide and water, which we expel by breathing). The ATP acts like electricity in our bodies, transferring electrons that make our muscles contract, our nerves send signals, our brains operate, and our hearts beat. When we eat food, our bodies break down the carbohydrates to glucose so that our cells can use the food for energy.

The other stuff we eat — things like vitamins, minerals, protein, and fat — are used as building blocks. For example, we make hormones out of the fat we eat, bone out of minerals, metabolic enzymes out of vitamins, and create new tissues out of protein. Our muscles specifically are primarily made from protein. Building and maintaining muscle means our bodies use the protein we eat in food to synthesize new muscle fibers so that we can maintain our strength. But in periods of food deprivation, when we aren’t taking in enough calories or carbs, our bodies focus on staying alive (i.e. maintaining energy levels) rather than focusing on repairing or creating new tissue. So, instead of using the protein to grow, it breaks down the protein we eat into amino acids through an alternative metabolic cycle and converts the amino acids into ATP. The same is true of the fats we consume when carbohydrates aren’t available for energy.

The word “ketosis” refers to the process of using fat for energy instead of glucose. This name comes “ketones,” which are the chemical breakdown products of fatty acids made by our bodies during this alternative metabolic pathway. The end result is the same as the end result from metabolizing glucose (ATP) but via an alternative pathway. This alternative pathway uses different metabolic enzymes which require different levels of vitamins. If these vitamins aren’t replenished, deficiencies result. This is why individuals on the ketogenic diet are at a higher risk of nutritional deficiencies than their non-dieting counterparts.

Byproducts of the ketogenic metabolic pathway are also different from the glucose pathway in terms of the waste products produced. Instead of just carbon dioxide and water, ketosis creates byproducts that cause kidney stones, inflammation, and more. Our bodies are smart, though. The immediate risks of running out of energy (i.e. death) outweigh the long-term risks of chronic inflammation and organ failure, so the body chooses to go into ketosis in such extreme cases so that it can stay alive until carbohydrates become available again, and the body can function normally.

The functionally normal, optimal state of the body is not ketosis.

The goal of functional medicine is to support the naturally-designed state of the human body. Ketosis does not fit into that picture. The ketogenic diet encourages a metabolically abnormal state, which creates an enormous risk for health problems, many of which are not yet understood.

Fad diets are trendy because our culture is obsessed with weight loss, and many folks achieve weight loss quickly with the keto diet. The reason for this has nothing to do with ketosis and everything to do with the fact that such a restrictive diet is almost always accompanied by a calorie deficit. The keto diet is not a magic pill for weight loss. It is not a simple health solution. It’s everything but!

Cultivating a healthy, balanced lifestyle does not need to be complicated. It does not need to include extreme measures like a carb-restricted, high-fat diet. It doesn’t require excessive exercise, calorie counting, exotic and overpriced ingredients, or high-end MCT oil supplements. Rather, it involves taking the time and energy to get to know our own individual bodies, treat them with kindness, and respond appropriately to the signals they give us when something goes awry.