High-Protein Diet May Hurt Your Kidneys: Study
Thu, April 22, 2021

High-Protein Diet May Hurt Your Kidneys: Study

Recent study shows that High-protein diet may not be as "healthy" as it seems / Photo Credit: Oleksandr Prokopenko via 123rf


There are many benefits to maintaining a high-protein diet, such as for weight loss, having more sustained energy, better skin, nails, and hair, improved sleep, better workouts, stronger bones and tendons, better mood and focus, and helps the body recover faster from illness and injuries. Yet, a new study finds that HPD is not safe for kidney health.

A team of researchers from the University of California Division of Nephrology, Hypertension, and Kidney Transplantation, University of Chicago, and the  Centre Hospitalier Lyon Sud in France highlighted that a high-protein diet may hurt the kidneys of the dieters. While the person saves calories from such a diet, it also risks the health of their kidneys, particularly those with limited nephron endowment and at risk of chronic kidney disease.


Why HPD is bad for kidney health

Authors Kamyar Kalantar-Zadeh, Denis Fouque, and Holly M. Kramer explained that a high-protein diet leads to an increased glomerular filtration rate (GFR), a calculation that determines how well the blood is filtered by the kidneys and is used by doctors to determine the stage of chronic kidney disease. When GFR in kidneys is increased, it likewise results in glomerular hyperfiltration, which may also raise pre-existing low-grade chronic kidney diseases. HPD may also increase a person’s risk of de novo kidney diseases.

Fouque, who also served as chair of the European Renal Nutrition Working Group, said that recommending an HPD to an overweight diabetic patient may result in successful weight loss but it may also cause a severe loss of their kidney function. The researchers highlighted the harmful impact of a high protein diet may not affect people with healthy kidneys but those who are at risk of chronic kidney disease or with limited nephron endowment. This applies to obese and diabetic persons and those with reduced kidney function. Nephron endowment refers to the number of functioning nephrons that an individual has at birth.


Implementing and practicing the high-protein diet may hurt the kidneys of the dieters / Photo Credit: dolgachov via 123rf


The research, which appeared in the peer-reviewed medical journal Nephrology Dialysis Transplantation, serves as a warning in consideration of the rising number of individuals affected by type 2 diabetes and that 30 percent of people diagnosed with diabetes also suffer from CKD. They emphasized that advising people who are obese, diabetic, and those with a single kidney to eat a protein-rich diet is like “ringing the death bell for their kidney health.” 

There are also two studies linked to the findings of Kalantar-Zadeh and colleagues. The first one was an analysis of the dietary and kidney data from a prospective study of 4,837 Dutch patients aged 60 to 80 years old with a prior history of myocardial infarction and after the subjects participated in a clinical trial of low-dose omega-3 fatty acids. The findings showed a “strictly linear association” between high dietary protein intake (DPI) and a decline in kidney health. The higher the DP intake, the faster the kidney health decline would be.

The second study linked was the epidemiological research conducted among 9,226 South Koreans. The findings also revealed that people with high protein intake are at 1.3 higher risks of faster glomerular filtration rate loss.

Kalantar-Zadeh and colleagues said that the problem is that even those with mild chronic kidney disease follow the trend of eating a diet that is rich in protein because it is generally viewed as healthy. However, they are not aware that it would be a fast lane to kidney failure. This is why they wanted to raise awareness to the public to inform them about the other sides of HPD. 

Some sources of protein include eggs, lean meat, poultry and fish, seeds and nuts, dairy products like cheese, yogurt, and milk, soy products, legumes and beans, and some cereal-based and grain products.



Chronic kidney disease: statistics

The National Kidney Foundation published that CKD causes more deaths than prostate cancer or breast cancer. It affects about 37 million people in the United States, 15 percent of whom are adults. This means that more than one in seven adults are affected by CKD and 90 percent of those with such a condition may not even be aware that they have it.  Also, one in two persons with very low kidney function but are not on dialysis doesn’t know that they have chronic kidney disease.

The two main causes of CKD are high blood pressure and diabetes. From 2014 to 2016, the two were the culprits for nearly 75 percent of kidney failure cases recorded by the National Kidney Foundation. More than 3,500 kidneys are surgically discarded every year and the NKF is helping to utilize more of these organs for transplantation.

The US-based voluntary health organization added that the most effective means to combat CKD is early detection when the disease can be stopped or slowed. The treatment includes lifestyle changes, medications, exercise, diet, and treating the risk factors like hypertension and diabetes. Once the organs fail, a kidney transplant or dialysis is needed.  It is a stage of CKD called end-stage kidney disease or end-stage renal disease.