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The Canyon Ranch Guide To Weight Loss: The Real Risks Of A Keto Diet

Feb 16 2023
By Dr. Stephen Brewer
7 min read
The word keto made of food on a table.

To Keto or not to Keto? That is the weight loss diet question on the minds of many. Dr. Stephen Brewer, Medical Director of Canyon Ranch, answers.

In an excerpt from his new book, The Canyon Ranch Guide to Weight Loss: A Scientifically Based Approach to Achieving and Maintaining Your Ideal Weight ($24.95), Stephen Brewer, MD, Medical Director Canyon Ranch, tackles the subject of embracing a ketogenic diet and shares the long-term health conditions from this not-so-new, low-carb diet craze.

A very popular kind of diet is the ketogenic diet. The focus is to decrease carbohydrate intake. When there are no carbs to break down for energy, the body must metabolize fats for energy. The term “ketogenic diet” generally refers to a diet that is very low in carbohydrate, modest in protein, and high in fat. This combination of macro-nutrients can induce ketosis. Ketosis occurs when the body produces ketone bodies to supply energy for the body when it does not have enough glucose to perform that job. If you are in a ketotic state, those ketones will spill over into the urine. Therefore, urinary ketone levels are often used as an indicator of dietary adherence. This is why many who are committed to this diet will test their urine for ketones to make sure they are complying with the diet.

It is important to note that high-fat, low-carbohydrate ketogenic diets (KDs) are not new. This type of diet was first developed in the 1920s to treat pediatric refractory seizure disorders. In recent years the use of what we call “KDs” has experienced a revival to include the treatment of adulthood epilepsies as well as conditions ranging from autism to chronic pain and cancer.

Health Concerns About Keto
There are several concerns I have with the ketogenic diets. Extreme carbohydrate restriction can profoundly affect diet quality. Very low-carbohydrate diets may lack vitamins, minerals, fiber, and phytochemicals found in fruits, vegetables, and whole grains. Low-carbohydrate diets are often low in thiamin, folate, vitamin A, vitamin E, vitamin B6, calcium, magnesium, iron, and potassium.

Ketogenic diets are typically low in fiber, which is needed not only for healthful intestinal function but also for microbial production of beneficial colonic short-chain fatty acids, which enhance nutrient absorption, stimulate the release of satiety hormones, improve immune function, and has anti-inflammatory and anti-carcinogenic effects. Inadequate intake of these microbiota-accessible carbohydrates found in plant cell walls also increases gut permeability.

Intake of other protective dietary components normally found in many fruits and vegetables appear to be significantly lacking in a Keto diet. Examples are phytochemicals like flavanones and anthocyanins, which are antioxidants that help prevent chronic diseases such as cancers.

Most individuals who go all in with a low-carb ketogenic diet are so excited initially because they often observe a sudden rapid weight loss. Most people think it is due to loss of fat, but in reality, the early rapid weight loss is most likely due to a loss of fat-free mass, which includes body water, glycogen, protein, and contents of the gastrointestinal tract. The body is designed to use glucose for fuel, and when it is taken away because of the low-carb diet, the body immediately goes for stored glucose, which is called glycogen. Glycogen is in the liver and muscles. It is stored glucose that is held together by simple water bonds. When the body breaks down the glycogen molecules to access the glucose, water is released and is eventually eliminated through the kidneys. So that initial weight loss is not a loss in fat. It is only a loss in water from the glycogen bonds.

Inflammation & Liver Disease
An increased level of inflammation with a ketogenic diet is also a concern. In the 2021 metabolic ward trial by Hall et al. comparing the effects of an animal-based ketogenic diet and a plant-based, low-fat diet, the inflammatory maker for inflammation called the high-sensitivity C-reactive protein was substantially higher while on the ketogenic diet as compared to the plant-based diet (2.1 vs. 1.2 mg/L; p = 0.003).

One last comment on the Keto diet is the prevailing concern that it may contribute to developing Non-Alcoholic Fatty Liver Disease (NAFLD). In epidemiological studies, diets high in saturated fat, trans fat, simple sugars, and animal protein (especially from red and processed meat) and low in dietary fiber and omega-3 fatty acids are thought to contribute to NAFLD. In the Rotterdam Study, those consuming the most animal protein were 54% more likely to have NAFLD than those consuming the least (OR 1.54, 95% CI, 1.20–1.98). Dietary components associated with reduced NAFLD risk include whole grains, nuts and seeds, monounsaturated fats, omega-3 fatty acids, vegetable protein, prebiotic fiber, probiotics, resveratrol, coffee, taurine, and choline.

This ketogenic diet, along with many other diets, seems to work at first, but they don’t seem to have staying power. Less than 20% of people that lose weight are able to maintain that weight loss. A common scenario I have witnessed over the years has been if I meet someone who I haven’t seen for a while and they look great because they have lost a significant amount of weight. When you ask them how they were able to lose their excess weight, more often than not, they will tell you they did it by following one of the new fad diets.

Unfortunately, the next time you see them, they often have gained back the weight they lost, and many times they gained back more weight than they originally lost. They will tell you they just could not maintain that crazy diet, and it did not fit into their lifestyle. They sometimes say that if only they had lost their weight by a reasonably healthy approach, they could still be absent those pounds.

A Ketogenic Diet Summary

  • A typical diet contains 48% carbohydrates, 32% fat, and 17% protein. Whereas most ketogenic diets start with carbohydrate restriction of less than 10% of the energy intake for about 2 months before starting a slow reintroduction.

  • Weight loss peaks at about 5 months; then weight is slowly regained.

  • Individuals that are on ketogenic diets have a tendency to eat less food. This appears to be related to a decreased appetite that is often seen in the Keto diet, with its composition of higher fat and protein compared to a more typical diet containing a higher carbohydrate content.

  • Observational data suggest long-term low carbohydrate intake might be associated with increased mortality.

This was excerpted from The Canyon Ranch Guide to Weight Loss: A Scientifically Based Approach to Achieving and Maintaining Your Ideal Weight by Dr. Stephen Brewer. Reprinted with Permission by the publisher, SelectBooks, Inc. Find it here.

Related Pathway: Integrative Weight Loss

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About the Expert

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Stephen C. Brewer

MD, ABFM, Medical Director

Dr. Brewer knows from experience that the key to balancing a busy professional life with personal wellness is to find a plan that works with your lifestyle. He is passionate about helping our guests discover that balance for themselves.

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