High-to-medium protein, low-carb diets ending in the letter “O” appear to be all the rage in current dieting culture. Everyone wants a safe, fast and effective way to lose weight and hopefully keep it off in the long term. The Ketogenic or Keto diet is one such popularized dieting plan that needs further scientific study and analysis to truly determine its efficacy and safety. The Harvard School of Public Health published its “Diet Review: Ketogenic Diet for Weight Loss” to examine what is currently known about the magical sounding Keto.

What’s Keto?

The keto diet is a low-carb, fat-rich eating plan with a history spanning centuries as a treatment booster for specific medical conditions, such as medication resistant pediatric epilepsy. It has also been utilized in closely monitored circumstances for polycystic ovary syndrome, cancer, diabetes and Alzheimer’s. Yet, the diet has gained attention as a possible weight loss tool due to the hyper fixation around low-carb diets spanned by the Atkins diet of the 1970s. Other low-carb diets are moderate in fat, but the ketogenic diet sets itself apart with its recommended 70-80% fat content.

The ketogenic diet is intended to deprive the body of glucose and encourage the body to use fat converted into ketones as its primary fuel source. The brain needs glucose most readily, at roughly 120 grams daily, as it can’t store it. When someone fasts or cuts out carbs, the body uses stored glucose from the liver and even temporarily breaks down muscle for its glucose needs. Over three-to-four days of continued carb reduction and depleted glucose, the hormone insulin decreases in the blood as the body uses fat to fuel itself. The ketone bodies are produced from the liver and fat, fueling the body instead of glucose.

This process of ketone bodies accumulating in the blood is called ketosis, which healthy individuals naturally experience in fasting periods like after sleep or after intense exercise. The primary immediate health concern with a ketogenic diet is if the diet will propel the body into ketoacidosis, which is when blood levels of ketones reach a harmful excessive level in the body and a person’s insulin production is not enough to combat it. Ketoacidosis is most common for type 1 diabetics due to their lack of insulin production and in rare cases, nondiabetics on prolonged extremely low-carb diets. The risks of ketoacidosis and the rate of ketosis varies by individual, fluctuating based on factors such as body mass index and resting metabolism.

The Keto Menu

Like most diets, it isn’t an exact science for the ratio of nutrients that a person should take in to maximize the desired effect. In general, the suggestion for keto diet is 70-80% fat from daily calories, then 10-20% protein and 5-10% carbs, less than a medium bagel. Protein is limited in this diet compared to other low-carb programs because it can prevent ketosis. A keto diet aims for enough protein to preserve lean body mass and muscle but still allows for ketosis.

There are several popular keto plans out there, so suggested foods may vary, but in general, keto diets permit:

  • Cocoa butter, lard, poultry fat, and most plant fats (olive, palm, coconut oil)
  • High-fat foods like avocado, coconut meat and certain nuts (macadamia, walnuts, almonds, pecans)
  • Seeds (sunflower, pumpkin, sesame, hemp, flax)
  • Some dairies, though it depends on the level of lactose. Butter and hard cheeses are sometimes allowed due to lower amounts of lactose.
  • Pork, bacon, wild caught fish, organ meats, eggs and tofu are on the list. Grass-fed beef and free-range poultry are recommended as they have slightly higher levels of omega-3 fats. In general, protein is moderate in this diet.
  • Non-starchy vegetables, such as leafy greens, cauliflower, broccoli, asparagus, Brussels sprouts, onions, mushrooms, summer squash, cucumber and celery.
  • Fruit is limited, mostly berries in small portions.

Foods not allowed on the keto diet include:

  • Any and all whole or refined grains, flour products
  • Added or natural sugars in food and drinks
  • Starchy vegetables like butternut squash, corn or potatoes
  • Most fruits and all fruit juices
  • Legumes, especially beans, lentils and peanuts
  • Most beers and wines (unless low-carb) or any beverages with added sweeteners.

The Research and Possible Benefits

 In the short-term, a ketogenic diet has been shown to promote beneficial metabolic changes. Weight loss has been seen to improve, as well as insulin resistance, high blood pressure and cholesterol or triglyceride levels. It is theorized that keto could be helpful for type 2 diabetes as well. Some keto supporters have noticed less food cravings and a decrease in appetite. There are theories that the increased ketones in the blood also help curb appetite, as well as more efficient calorie expenditure and promotion of fat loss instead of body mass. Though there have been many studies conducted on keto diets, they were all in the short term of roughly six months or less, so it’s unclear, at best, what a keto lifestyle over years might look like. Not to mention, over 50% keto attempters end up becoming frustrated by the strict dietary rules and cannot keep up the diet for a significant period, according to another Harvard Keto related article.

Possible Dangers of Keto

 A high-fat diet is most likely not for everyone, as it might prove difficult to maintain and produce unwanted symptoms. Not to mention, restricting carbs severely can increase hunger and fatigue, as well as lower mood and increase irritability, headaches and confusion.

Essentially, we don’t know what we don’t know in terms of keto side effects in the long-term, but there is some concern over possible increased risk for kidney stones, osteoporosis and higher uric acid levels that can result in gout. Nutrient deficiencies could also arise, such as lack of vitamin C due to fruit restriction. There are a lot of unanswered questions surrounding who this diet is safe for and in what periods of life.

Summary

Overall, the weight loss effects of a keto diet compared to conventional weight loss plans has not yet shown to be significantly different, so the benefit to most dieters does not seem to be present compared to the work involved. Like with any other major dietary plan, it is crucial to consult a dietitian and your primary care professional to ensure a safe and effective nutritional plan of action.

To learn more about Nutrition as a career, please visit Life University’s Bachelor of Science in Nutrition page.

References

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