Myths & Facts about keto

Numerous studies show that the ketogenic diet has helped athletes improve their body composition, trim fat, maintain performance and improve recovery. These studies have included marathon runners, triathlon competitors, CrossFit athletes, gymnasts, and other athletes performing high intensity and interval exercises.

One study found that after 12 weeks eating a ketogenic diet, endurance athletes cut body fat, increased oxidation and sprint power, and performed better overall on a critical power test compared to athletes on high-carb diets.

The ketogenic diet has actually been endorsed by the American Diabetes Association as the best diet to control blood sugar for people with Type 2 diabetes. Some studies have shown that extreme caloric restriction can also reverse diabetes, but continued starvation is largely unsustainable.

No other diet has demonstrated more promising results for Type 2 diabetes than one very low in carbohydrates.

Upwards of 17 scientific studies support the idea that carbohydrate restriction works to manage blood sugar, or glycemia, in patients with diabetes.

Upon starting the diet, some patients report symptoms like fatigue, headaches, and muscle aches. However, these short-lived symptoms are, in fact, a sign that the diet is working, and the body is switching over from burning glucose as fuel to burning fat. This transition involves upregulating certain enzymes and down-regulating others; it is a profound shift for the human body that can have uncomfortable symptoms. However, these side effect usually last only 3-4 weeks.

While it’s true that low-carb diets do raise the so-called bad LDL-cholesterol in some people, it’s important to note that LDL-C, when influenced by diet, has never been shown to have any effect on cardiovascular risk.

More importantly, the ketogenic diet also reliably raise the “good” HDL-cholesterol, while also improving most other cardiovascular markers, including blood pressure, as this study shows. Thus, the overall effect on cholesterol and other markers for heart disease is positive.

One study found carbs to be the “main culprit” in causing acne. However, another study found that low-glycemic diets lessened acne. What’s more, a review conducted by Italian researchers suggested that the keto diet could target acne by reducing inflammation and levels of insulin and IGF-1 — all known causes of acne.

Patients with gastroesophageal reflux disease (GERD) have been shown to improve after eating very low carbohydrate diets. Another study found increased carb-intake worsened GERD, while a high-fat, low-carbohydrate diet reduced symptoms. And two studies have linked esophageal diseases, including Barrett’s esophagus (BE) and GERD, to sugar and carbohydrate intake.

The European Association for the Study of the Liver actually cites a low-carbohydrate diet as a way to treat the disease. Studies show that cutting carbohydrates and particularly fructose, or sugar from plants, works to improve liver fat metabolism.

What’s more, high-carbohydrate diets have been associated with worsening non-alcoholic fatty liver disease.

There seems to be no foundation for this claim. People eating diets very low in carbohydrates and high in fats and proteins have been found, in one study, to enjoy better sleep quality, meaning they spent more time in deep sleep than those on high-carbohydrate, low-fat diets. A survey of 1,580 low-carb consumers published by the Journal of Insulin Resistance found that while more than 11% of respondents reported using sleep-aids before beginning their low-carb diet, less than 5% reported using them after their diet.

Multiple studies have found that diets higher in fat prevent gallstone formation. Examples are here and here. Meanwhile, diets low in fat actually increase gallbladder volume and may increase the risk of gallstone development, as do diets high in sugar and carbohydrates.

Studies have demonstrated that the keto diet may in fact be ideal for long term weight management. One meta-analysis found that individuals following very low-carbohydrate ketogenic diets lost more weight in one year than those on low-fat diets.

A survey published in the Journal of Insulin Resistance found that three of four respondents on a low-carb diet reported losing 10 pounds or more; one-third reported losing more than 30 pounds. Six out of 10 respondents who were on the diet two years or more reported losing 20 pounds or more and 46% said they lost 3 inches from their waists.

The ketogenic diet does not limit calories; people can eat as much as they like so long as they restrict carbohydrates. This means that people don’t have to endure long periods of feeling hungry—which is why the ketogenic diet tends to be sustainable.

The survey in Journal of Insulin Resistance found that before respondents started their low-carb diets, nearly nine of 10 experienced intense hunger between meals. Once on the diet, only 3.5% said they grew hungry between meals. Respondents reported similar improvements in other aspects of their physical and psychological well-being.

Of the 1,580 survey participants, more than half reported staying on a low-carb diet for at least one year, and 34% reported more than two years. Further, those on the diet for two years or more said that they had largely maintained their weight loss.