A recent study published by the European Association for Dialysis (ERA-EDTA) concludes there should be firm warnings about high-protein, low-carb diets for people with diabetes who are at risk of low-grade chronic kidney disease, which total about 30% of all people with T2D.

Low-Carb: Weight-loss + Kidney Damage for Some

While reducing your carbohydrate intake can easily improve blood sugar levels, it inevitably results in an increased intake of dietary fat and protein. 

The promise of losing weight is why a high-protein diet is often recommended to people with diabetes or who are obese,” explains the report, “but they are especially vulnerable to the kidney-harming effects of high-protein intake.”

Even in those without diabetes, low-carb/high-protein diets have become very popular and often lead to noticeable weight-loss, an overall healthier diet (because removing carbohydrates often removes processed, packaged foods), and overall increased energy.

Researchers Kamyar Kalantar-Zadeh, Holly M Kramer, and Denis Fouque, are adamantly pushing for better education around these types of diets for patients with low-grade or fully-developed kidney issues. “

“We may save calories, but we may also risk the health of our kidneys,” they explained in the report. 

“A high-protein diet induces glomerular hyperfiltration, which, according to our current state of knowledge, may boost a pre-existing low-grade chronic kidney disease, which is often prevalent in people with diabetes.”

What is Your “Glomerular Filtration Rate” or GFR?

Glomerular hyperfiltration means your kidneys are not filtering your blood properly and letting too many waste products through. 

Let’s take a closer look.

Your body’s “GFR” measures how well your kidneys are working. 

The glomeruli are small filters in your kidneys that help filter waste from your blood. When signs of kidney disease are already established, high-protein diets can put further stress on these filters and further worsen their functioning.

The reports add that encouraging an overweight patient with type 2 diabetes to follow a low-carbohydrate diet should only come after careful examination of their kidney health and overall blood sugar management.

Researchers found that patients with the highest protein intake had a 1.3 higher risk of faster GFR loss.

Patients with Type 2 Diabetes & Obesity at Highest-Risk

If a patient with type 2 diabetes has been struggling with high blood sugar levels and a high A1c for a number of years, it’s very possible they may already have signs of kidney disease — a common complication of chronically high blood sugar levels.

Researchers estimate that approximately 30 percent of patients with type 2 diabetes have some degree of kidney disease.

“To recommend a high-protein diet to an overweight diabetes patient may indeed result in loss of weight, but also in a severe loss of kidney function. We want one, but we also get the other,” explains the research team.

While it’s already known that those with established kidney issues should avoid excessive protein consumption, it’s too often overlooked in patients who have a very high risk of kidney disease but haven’t been tested for it because it’s still “low-grade” and thus they aren’t experiencing symptoms. 

“By advising people — especially those with a high risk for chronic kidney disease, namely patients with diabetes, obese people, people with a solitary kidney and probably even elderly people — to eat a protein-rich diet, we are ringing the death bell for their kidney health and bringing them a big step closer to needing renal replacement therapy.” 

Instead, the recommendation is to focus on the following nutrition guidelines:

• Reduce or remove your sugary beverage intake
• Limit packaged, processed foods
• Focus on getting more whole food vegetables and fruits
• Limit protein intake to 50 grams per day or less after consulting with your healthcare team
• Drink plenty of water

Talk to your healthcare team about having your GFR and overall kidney health tested to determine if a higher protein-consumption is a safe choice for you.