Diabetes and the keto diet
Resident Pharmacist
Walgreens and Northeastern University
The keto diet
One of the top trending diets today is the low-carbohydrate diet—some popular variations you may have heard of include the keto diet, paleo diet, and the Atkins diet. In the 1920s, doctors at the Mayo Clinic developed a specialized dietary plan to treat epilepsy called the ketogenic or keto diet—a diet plan that is very high in fat, moderate in protein, and very low in carbohydrates (carbs).
The typical keto diet consists of at least 70-80% of calories derived from fat, 5-10% from carbs, and 10-20% from protein. To meet these requirements, followers of the keto diet need to include fats, such as avocados, oils, nuts and full-fat hard cheeses at each meal and snack, while completely eliminating or strictly limiting carb-containing foods, such as whole grains, legumes, fruit and some vegetables. There is solid evidence for the keto diet in the treatment of epileptic seizures. Additionally, the keto diet is being studied for managing weight and diabetes.2
Understanding the Keto Diet
Normally your body runs on energy from glucose (sugar), which is provided from carbs. The goal of the keto diet is to force your body into using fat stores, instead of carbs, for energy. By strictly limiting the amount of carbs you eat (typically less than 50 grams a day), the availability of sugar drops. Your body begins to break down stored fat into substances called ketones. Ketones accumulate in your blood and replace sugar as the primary fuel for the body. This metabolic state is called ketosis. To stay in ketosis, you need to continue to restrict carbs. However, the exact number of carbs that should be limited in the diet varies from person to person.3 Eating too many carbs or too much protein can prevent ketosis.
Ketosis vs. Ketoacidosis
Ketosis is the body's natural response during periods of fasting or when following a strict low-carb diet. It's believed that when healthy people closely follow the keto diet, ketones should not reach dangerous levels in the blood. This is because the body will use ketones for fuel, and healthy people will make enough insulin (a hormone made by the pancreas that's needed to move sugar from the blood to the cells) to keep ketones from accumulating to harmful levels. However, when insulin levels are extremely low in people with type 1 diabetes or advanced type 2 diabetes, ketone production can become dangerously high and cause the blood to become acidic. Without enough insulin, the body continues to break down fat to convert into energy. When ketones reach a dangerous level, it's called diabetic ketoacidosis (DKA). DKA is an emergency medical situation that can be caused by the lack of insulin or infection.4
Can the Keto Diet Help Diabetes?
At this time, research on the keto diet in people with diabetes is in its early stages. Many people with type 2 diabetes are overweight, and losing and maintaining a healthy weight is a key part of managing diabetes. Studies show that following a low-carb diet, such as the keto diet, can aid in weight loss, but it isn't yet known if it's effective or safe to eat this way long-term. What's more, sustaining the keto diet may be difficult as you must severely restrict carbs and eat significantly more fats. And while early research shows that a low-carb diet may improve blood sugar control in people with type 2 diabetes, these diets should be approached with caution. This is because consuming excess unhealthy fats is a risk factor for cardiovascular (heart) disease, and having type 2 diabetes already increases the risk of heart problems. People with type 1 diabetes should also be wary when following the keto diet due to the risk of DKA. Discuss the keto diet or any other diet with your health care provider before you try it, especially if you take any diabetes medications, including insulin.
The Bottom Line
Diet is an important part of diabetes treatment. Eating a nutritious diet can also help with obesity, high blood pressure, and high cholesterol. By eating healthy, you can manage your health and prevent long-term heart or kidney problems.5
In conclusion, there is no one-size-fits-all diet plan for healthy eating. The scientific data is still limited for using the keto diet to manage diabetes.6 Work with your doctor, registered dietitian, and diabetes educator to find a sustainable diet plan to meet your preferences, needs, and goals.
Published on May 25, 2020
References
1. Diet Review: Ketogenic Diet for Weight Loss. (2019, May 22). Retrieved February 16, 2020, from https://www.hsph.harvard.edu/nutritionsource/healthy-weight/diet-reviews/ketogenic-diet/
2. Bolla, A. M., Caretto, A., Laurenzi, A., Scavini, M., & Piemonti, L. (2019). Low-Carb and Ketogenic Diets in Type 1 and Type 2 Diabetes. Nutrients, 11(5), 962. https://doi.org/10.3390/nu11050962
3. Kennedy, M. N. (n.d.).UCSF Diabetes Education Online. Retrieved from https://dtc.ucsf.edu/types-of-diabetes/type2/understanding-type-2-diabetes/how-the-body-processes-sugar/ketones/
4. DKA (Ketoacidosis) & Ketones. (n.d.). Retrieved February 16, 2020, from https://www.diabetes.org/diabetes/complications/dka-ketoacidosis-ketones
5. Marion, DW. Losing Weight: Beyond the Basics. In: UpToDate, Post, TW (Ed), UpToDate, Waltham, MA, 2014.
6. Joshi S, Ostfeld RJ, McMacken M. The Ketogenic Diet for Obesity and Diabetes—Enthusiasm Outpaces Evidence. JAMA Intern Med. 2019;179(9):1163–1164. doi:10.1001/jamainternmed.2019.2633