Nutrition / Popular Diets

Why You May Have High Blood Glucose on Keto

Can diets that limit sugar, actually increase glucose in our blood?

The ketogenic diet (known as keto for short) is the latest craze and lifestyle alteration trend that aids with weight loss, weight management, and, for some, overall health. The ketogenic platform follows a particular set of guidelines: consume seventy to seventy five percent of your daily calories from fat, fifteen to twenty percent protein, and five percent from carbohydrates.

By following the keto diet and incorporating healthy habits like exercise (like the many cardio and strength training programs offered by the Aaptiv app), sleep, and meditation, many have been seeing an improvement in size measurements and mental clarity.

On the other hand, some are surprised to find unexpected numbers from the doctor’s office while on the ketogenic diet. One of these results is usually high levels of glucose (other wise known as sugar) in the blood. How is it, that lowering carbohydrate and sugar consumption can lead to high blood glucose? We spoke with doctors and medical professionals to help break down how the ketogenic diet could be causing high levels of blood sugar.

You’re eating too much fat

The ketogenic diet is a big fan of healthy fats, but could too much fat could be hurting our blood glucose levels. Dr. Nikola Djordjevic, MD from explains that the general assumption of the ketogenic diet lowering blood glucose levels is only partially correct. “Some individuals do experience high levels of glucose in their blood while on a ketogenic diet. The reason for this is that substituting fat for sugar isn’t exactly sustainable over time,” she explains. “What’s important to understand is that the glucose in your blood is dependent on both carbohydrate and fat intake.” According to Dr. Djordjevic, when you consume too much dietary fat, you can actually increase your insulin resistance. This results in high glucose levels in your blood and can lead to conditions such as high cholesterol. It can also increase your risk of developing chronic diseases.

While it’s true that “cutting down on carbs will definitely help reduce glucose levels in the short term,” says Dr. Djordjevic, “I wouldn’t recommend loading up on dietary fat in order to achieve ketosis, since, in the long-term, it can affect your insulin resistance and lead to more serious health conditions.”

Your body is building up insulin resistance

As previously mentioned by Dr. Djordjevic, it’s possible that eating too much fat can in fact lead to insulin resistance. But what is insulin resistance and how can the keto diet cause it? Dr. Carla Hightower, physician and founder of Living Health Works, explains, “The keto diet impairs your muscles’ ability to take up glucose in response to insulin (a hormone in the body which regulates blood sugar)—a disorder called insulin resistance. Normally, insulin acts like a key, unlocking muscle cell membranes and allowing glucose to enter and serve as fuel,” she says. “But, when muscle cells become insulin resistant, glucose accumulates in the blood instead of entering the cells where it belongs. As a result, the keto diet increases the risk for high blood glucose (diabetes), low energy, and fatigue.”

Additionally, according to Dr. Hightower, “On a keto diet, the body tends to burn not only fat but muscle, as well. This can weaken the muscles and make it difficult for people to exercise. Consequently, individuals on a keto diet are more likely to gain weight, which, by itself, causes insulin resistance (and repeats the cycle). Although for some people, the keto diet may result in short-term weight loss, the diet is unhealthy and unsustainable for most people long term.”

You’re eating too much protein

Different than diets like Atkins, where you’re primarily eating protein, keto has a particular percentage of protein (macro-nutrient) that you’re allowed to consume in a day. While many don’t see an issue with eating more protein than allotted (it’s not carbohydrates right), there’s an underlying truth that you may not be aware of.

Carolyn Dean, MD, ND, bestselling author, and health and wellness thought leader explains how higher levels of glucose in your blood can occur. “[If you’re] consuming too much protein, it will convert to sugar, which will prevent you from achieving ketosis (and lead to excess levels of glucose). Protein consumption should not be more than ten to thirty percent of what you are eating as part of your daily meals (while on keto),” she says.

Yes, it’s true that excess protein in the body can be converted into sugar. When the body has fed its muscles with protein to maximum capacity, and has excess protein levels to store, they’re converted into glucose to burn. Unfortunately, if you’re not burning the excess glucose through cardio exercise (like many of the workouts featured on the Aaptiv app), it can be stored extra weight and housed higher glucose levels in the blood.

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