Is Too Much Protein Bad for Your Kidneys?
One of the most often asked nutrition-related questions is whether too much protein bad for your kidneys? particularly by those who follow high protein diets for healthy ageing, weight control or muscle growth. Although protein is a necessary nutrient, misconception is common regarding protein and kidney health. In reality a person’s general health, kidney disease and overall nutrition play a significant role than just consuming more protein. From the standpoint of clinical nutrition, this article discusses high protein diet safety, what the most recent research indicates, why this has gained popularity and who should exercise caution.
Is Too Much Protein Bad for Your Kidneys?
Building muscle, boosting immunity, repairing bodily tissues, generating hormones and enzymes all depend on protein. Protein is broken down into amino acids during digestion, and the kidneys filter and eliminate waste materials after protein digestion. Many people wonder is too much protein bad for your kidneys and believe that consuming more protein inevitably destroys healthy kidneys, since the kidneys have to work harder to remove these waste products after eating too much protein. Protein and kidney health should be assessed according to a person's medical history rather than making generalisations as research constantly demonstrates. In healthy people the kidneys briefly increase their filtration rate in response to mild increases in protein consumption. This is a typical physiological reaction that does not always signify injury.[1]
Why the Protein Myths Exists
Studies involving people with chronic kidney disease (CKD) are primarily responsible for the assumption that protein damages the kidneys. Reducing dietary protein can help reduce the course of the illness in those with compromised renal function since damaged kidneys have trouble filtering the by-products of protein metabolism. However, this advice for CKD patients eventually spread to healthy people becoming one of the most prevalent protein misconceptions. This misconception is caused by a number of factors like research on renal illness is frequently misapplied to populations in good health, renal damage is sometimes confused with transient increases in renal filtration and unhealthy eating habits that involve a lot of processed foods and salt are occasionally linked to high protein intake.[2]
What Science Says About Protein and Kidney Health
The idea that consuming more protein harms healthy kidneys is not supported by current studies. Even when consumed over long period of time high protein diets have not been demonstrated to affect kidney function in healthy individuals according to studies. In a similar way sports nutrition organisation acknowledge that increased protein consumption promotes healthy ageing, muscle maintenance and exercise recovery without raising the risk of renal disease in those with normal kidney function. The available data on the safety of high protein diet indicates increased protein metabolism is effectively accommodated by healthy kidneys. In healthy people there is no solid proof that protein causes chronic kidney disease. Drinking enough water remains important to support kidney health and function. In addition to sufficient hydration, overall dietary quality and concentrating on including a balanced diet with lean protein sources, whole grains, fruits, vegetables and healthy fats is important.[3]
Who Should Be Careful with Protein Intake?
Higher protein intake seems safe for the majority of healthy people, however specific dietary advice is needed for some populations.
- Existing kidney disease and nutrition – Excess protein can make the kidneys work harder and add to the accumulation of nitrogen containing waste products in those with underlying kidney disease. Protein recommendations are usually customised depending on kidney disease stage, status of dialysis, muscle mass and biochemical parameters. A nephrologist or renal dietician should always monitor protein restriction, it should never be self restricted.[4]
- Elderly individuals, individuals with long standing diabetes, etc. should speak with their healthcare providers before increasing their protein intake.
How Much Protein Is Too Much?
Since the amount of protein needed varies depending on age, exercise level, muscle mass and health concerns there is no common definition of too much protein. The daily protein recommendation are
- Adults in good health can consume 0.8 -1 g protein/kg body weight/day
- People that are active can consume up to 1.2–1.5g protein/kg body weight/day or more, this should be done under supervision of a health care professional.
- 1.0–1.2 g protein/kg for older persons, under medical supervision[5]
Rather than concentrating only on quantity one should focus more on a uniform distribution of protein throughout the day with superior sources of protein, sufficient consumption of fluids and well balanced meals with healthy fats, carbohydrates and high in fibre. These methods boost overall metabolic wellness and support kidney function.
Signs of Excessive Protein Consumption
Protein by itself might not harm healthy kidneys however high protein diets with poor water intake, can affect kidney function. The following are some indicators that a person may be consuming too much protein :
- Reduced consumption of fruits and vegetables
- Constipation
- Discomfort in the digestive system, bloating
- A higher consumption of processed meats that are rich in saturated fat and salt
Look out for these signs and take appropriate measures to include a balanced diet and protect kidney function.
High Protein Diet Safety
When done carefully increasing protein can help with recovery, weight management, muscular health and healthy ageing. Clinical dietitians advise on selecting low fat dairy, fish, poultry, eggs, beans, lentils, soy products and tofu as sources of lean protein. They also advise to increase nutritional diversity and incorporate a range of plant and animal proteins. Rather than taking the majority of your protein in one meal distribute it equally across all your meals. For a balanced diet combine protein with whole grains, vegetables and healthy fats. Drink enough water especially when increase protein intake, exercising or in hot weather. Steer clear of highly processed meats that contain a lot of salt and preservatives. Adhering to these evidence based guidelines promotes the safety of a high protein diet while assisting in the maintenance of long term health.
Conclusion
So is eating too much protein bad for your kidneys? According to recent research consuming more protein as part of a balanced diet does not harm kidneys in healthy people with good renal function. People who already have renal disease or certain medical conditions that call for customised dietary therapy are the main targets of this concern. Instead of being swayed by outdated protein myths concentrate on eating the right amounts of good quality protein that correspond to your level of activity, nutritional requirements and overall health. Before making significant dietary changes speak with a qualified dietitian or other healthcare professional if you have kidney disease, diabetes or any other medical conditions to understand about kidney disease nutrition.
[1] Antonio, J., Ellerbroek, A., Silver, T., Vargas, L., Tamayo, A., Buehn, R., & Peacock, C. A. (2016). A High Protein Diet Has No Harmful Effects: A One-Year Crossover Study in Resistance-Trained Males. Journal of nutrition and metabolism, 2016, 9104792. https://doi.org/10.1155/2016/9104792
[2] Antonio, J., Peacock, C. A., Ellerbroek, A., Fromhoff, B., & Silver, T. (2014). The effects of consuming a high protein diet (4.4 g/kg/d) on body composition in resistance-trained individuals. Journal of the International Society of Sports Nutrition, 11, 19. https://doi.org/10.1186/1550-2783-11-19
[3] Kalantar-Zadeh, K., & Fouque, D. (2017). Nutritional Management of Chronic Kidney Disease. The New England journal of medicine, 377(18), 1765–1776. https://doi.org/10.1056/NEJMra1700312
[4] National Kidney Foundation. (2015). Nutrition and chronic kidney disease (Stages 1–4): Are you getting what you need? https://www.kidney.org/sites/default/files/11-50-0114_nutrition_chronic_kidney_disease_stage1-4.pdf
[5] Jäger, R., Kerksick, C. M., Campbell, B. I., Cribb, P. J., Wells, S. D., Skwiat, T. M., Purpura, M., Ziegenfuss, T. N., Ferrando, A. A., Arent, S. M., Smith-Ryan, A. E., Stout, J. R., Arciero, P. J., Ormsbee, M. J., Taylor, L. W., Wilborn, C. D., Kalman, D. S., Kreider, R. B., Willoughby, D. S., Hoffman, J. R., … Antonio, J. (2017). International Society of Sports Nutrition Position Stand: protein and exercise. Journal of the International Society of Sports Nutrition, 14, 20. https://doi.org/10.1186/s12970-017-0177-8