A low carbohydrate diet plus a sodium glucose contransporter-2 (SGLT2) inhibitor was found to be safe and effective for weight loss and glycemic control in patients with diabetes and chronic kidney disease.
The ketogenic diet—a low carbohydrate (LCD) that aims to induce ketosis (a state during which the body breaks down stored fat instead of glucose for fuel)—was the most popular Google search related to diets in the United States in 2020; in total, 25.4 million people conducted unique searches of it, according to a review published in Missouri Medicine.1
However, the ketogenic diet could serve as more than a trend. According to Johannes Kovarik of the Medical University of Vienna in Austria, a low carbohydrate diet (LCD) or very low carbohydrate diet (VLCD) could be an effective intervention for patients with diabetes and chronic kidney disease (CKD). Kovarik presented these findings in a session titled “Ketogenic Metabolic Therapies for CKD” at the American Society of Nephrology (ASN) 2023 Kidney Week Annual Meeting in Philadelphia, Pennsylvania.2
“We now have 2 ways to approach this problem,” Kovarik said during the session. “One way is with drugs. The other way is choosing dietary components.”
In 2020, the Kidney Disease Improving Global Outcomes (KDIGO) organization updated dietary recommends for patients with CKD and diabetes, highlighting a diet individualized to the patient that was inclusive of ample vegetables, fiber, legumes, whole grains, plant-based proteins, nuts, and unsaturated fats. According to Kovarik the diet should be low in processed meats, refined carbohydrates, and sweetened drinks.
The ketogenic diet also limits carbohydrate consumption to less than 50 to 60 grams daily while maintaining sufficient protein intake, according to Kovarik. Serum ketone B-OHB should also be greater that 0.5 millimeters and, in theory, entering ketosis effectively should help patients to achieve stable blood insulin and glucose, Kovarik said. Insulin is an important therapeutic target for diabetes and hypertension.
“Keeping your insulin level low is key,” he explains. “This will reduce your inflammation, your inflammatory pathways, reduce accelerated stress, and can also improve insulin resistance.”
Insulin resistance is the “common denominator” in hypertension and diabetes, according to Kovarik. Hypertension is linked to diabetes, which is the most common cause of CKD, withinsulin resistance linked to all 3 conditions (hypertension, CKD, and diabetes), as well as obesity and pre-diabetes, Kovarik explained. Without intervention, these conditions may lead to cardiovascular disease.
“If you look into the future with this epidemic of kidney disease, obesity, pre-diabetes, diabetes, and hypertension [and] we keep marching, we will have a problem,” Kovarik said during the session.
In a pivotal study published in Lipids in 2008, the ketogenic diet decreased hemoglobin A1c(HbA1c), fasting glucose, weight, blood pressure, and visceral fat in patients with type 2 diabetes and hypertension. In addition, investigators in the ongoing Vienna Keto-CKD project observedthat LCD plus treatment with a weight loss medication, such as a sodium glucose contransporter-2 (SGLT2) inhibitor, can be safe and effective for weight loss for patients with CKD and type 2 diabetes.
The patients were able to work with psychologists and receive nutritional counseling, so thismultidisciplinary approach might be a successful lifestyle intervention, alongside current medications, according to Kovarik. Notably, the diet was effective for glycemic control--and in certain conditions it was found to reverse type 2 diabetes--and stabilized or improved globular filtration rate (GFR), Kovarik said.
Further, the dietary intervention has the potential to reduce morbid obesity (defined as a body mass index [BMI] of 30 or higher), and it can even serve patients with later stage (stage 3 or 4) CKD, along with patients of various economic or racial backgrounds, Kovarik said.
One of the primary concerns when practicing an LCD-VLCD is diabetic ketoacidosis, a condition caused by excess ketones in the blood, which are created when the body breaks down fat, according to Kovarik. However, Kovarik noted that promising studies have identified advanced CKD as protection against ketoacidosis, with more to come with this research.
This dietary approach is also being explored as a management approach for mental disorders, polycystic ovarian syndrome, epilepsy, and autoimmune diseases, among other conditions. Still, the diet is met with hesitancy among health care professionals, and more research will hopefully help to shed light on the full impact of LCD-VLCD for diabetes and CKD to protect against worsening condition and negative cardiovascular outcomes, Kovarik said.
“The first premise of our work is patient safety and the best investment that we can do in our patients,” Kovarik said during the session. “We'll continue to look at this diet on risk factors.”
1. McGaugh E, Barthel B. A Review of Ketogenic Diet and Lifestyle. Mo Med. 2022; 119(1): 84–88. PMID: 36033148; PMCID: PMC9312449.
2. Kovarik J. Ketogenic Metabolic Therapies for CKD. Session. ASN 2023 Kidney Week Annual Meeting. November 2 to 5, 2023. Philadelphia, PA.