Popular high protein diets have been shown to help people lose weight and are sometimes recommended for people with type 2 diabetes. But such diets could also be putting long-term followers at risk of developing irreversible kidney damage, experts from the European Renal Association have warned.
Writing in the journal Nephrology Dialysis Transplantation Kamyar Kalantar-Zadeh, Holly M Kramer and Denis Fouque challenge what they call the ‘dogma of avoiding carbohydrates and substituting them with proteins’.
The authors of the editorial say that a ‘tough warning label’ should be slapped on modern eating habits. They write: “We may save calories, but we may also risk the health of our kidneys. The promise of saving calories and losing weight is why a high-protein diet is very often recommended to people who suffer from diabetes or who are obese. But the crux of the matter is that these groups of people are especially vulnerable to the kidney-harming effects of a high protein intake.”
Professor Fouque, a past-chair of the European Renal Nutrition Working Group, explains the science: “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, by the way, is often prevalent in people with diabetes. It might even increase the risk of de novo kidney diseases.
We are ringing the death bell for their kidney health
“To put it in a nutshell: 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.
“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.
“These people do not know that they are taking the fast lane to irreversible kidney failure.” Prof Fouque and his ERA-EDTA colleagues want to start an information campaign and raise awareness for this problem among the general population. “It is essential that people know there is another side to high-protein diets, and that incipient kidney disease should always be excluded before one changes one’s eating habits and adopts a high-protein diet.”