Protein Intake & Kidney Health: What's The Connection?

Did you know that Chronic Kidney disease is the 6th fastest-growing cause of death in India? In India, approximately over 7.8 million people have acute kidney diseases. Nearly 1.7 million people annually suffer from acute kidney diseases in the world. 

Although the causes of kidney diseases can be many, they could be diabetes, high blood pressure, heart disease, a high protein diet, use of certain medications, and more.

Here in this article, we will cover the connection between protein intake and kidney health. 

Do you believe that a high-protein diet can impact your kidney health? Well, you will find your answer in this article. So, let's get started.

Understanding Kidney Function

The kidneys play a key role in- 

• Filter out the waste and toxic substances from the blood
• Balance fluid and electrolyte levels
• Regulate blood pressure levels
• Release hormones that promote red blood cell production and bone health

Each kidney contains about one million nephrons, the microscopic units that filter blood and remove excess fluids and toxins through urine. Kidneys filter out nearly 50 gallons of blood daily, ensuring internal environment stability.

One of the kidneys' primary functions is regulating the glomerular filtration rate (GFR), which measures how well they filter waste. A normal GFR is 90 mL/min/1.73 m² or higher but declines with age or due to kidney disease. Kidneys filter protein by-products, urea, that result from protein metabolism. Excessive protein consumption can damage kidneys and cause kidney problems.

The Role of Protein in the Body

Protein is necessary for:

• Building and repairing tissues
• Enzyme and hormone production
• Immune system support
• Providing energy when carbohydrate reserves are low

Excessive protein consumption from animal sources can strain the kidneys, while insufficient protein can lead to muscle loss and weakened immunity. A well-balanced diet with plant-based and lean animal proteins supports optimal health and kidney function.

Protein and Kidney Health: The Connection

Protein is vital for overall health, but insufficiency or excessive intake can directly impact kidney functioning. 

About 90% of protein metabolic waste is excreted by the kidneys. As a result, a high-protein diet may cause glomerular hyperfiltration and damage to the kidneys.

Excessive protein intake from animal sources can worsen renal function and cause intraglomerular hypertension, resulting in kidney hyperfiltration, glomerular injury, and proteinuria. However, long-term high protein intake may lead to CKD.

In addition, people with chronic kidney disease (CKD), diabetes, or hypertension should be cautious, as excessive protein can accelerate kidney function decline. High-protein diets may also lead to dehydration, increased calcium loss, and a higher risk of kidney stones due to excess nitrogen excretion.

How Protein Affects Kidney Health?

The impact of protein on kidney health depends on the amount consumed, people's health conditions, and the type of protein sources.

• Excessive Protein Intake and Kidney Strain

Excessive protein can increase the kidney's workload and produce more waste products like urea and ammonia.

• How much protein is safe for kidneys?

The recommended protein intake may vary based on kidney function and overall health status.

Protein is essential for your body, but how much you need depends on your age, activity level, and overall health. What is the recommended protein intake?

• General Recommendation—Protein should make up 10% to 35% of your daily calories. If you eat 2,000 calories per day, that means 50 to 175 grams of protein daily.
• For the Average Adult—To prevent deficiency, people who live sedentary lifestyles should consume 0.8 grams of protein per kilogram of body weight. For example, if your weight is 165 pounds (75 kg), you should take 60 grams of protein daily.
• For Adults Over 40-50—As you age, you naturally lose muscle mass (sarcopenia). Increase protein intake to 1-1.2 grams per kilogram to help maintain strength and independence. A 165-pound person should get 75-90 grams of protein daily.
• For Active people, if you exercise regularly, you need more protein:
• Light to moderate exercise- 1.1-1.5 grams per kilogram
• Strength training or endurance sports- 1.2-1.7 grams per kilogram
• More than 2 grams per kilogram per day is considered excessive.
• For Overweight people, using your total weight to calculate your protein needs might overestimate your requirement. A dietitian can help determine the right amount for your body.
• For individuals with kidney issues, 0.6 to 0.8 grams per kilogram is recommended. Always consult your doctor before consuming any specific amount of protein. 

• Protein Sources: Which Are Better for Kidney Health?

Choosing the right protein sources can help maintain kidney health. Preferred sources include:

• Plant-based proteins: Lentils, chickpeas, tofu, quinoa, nuts and seeds (Almonds, Walnuts, Chia, Flaxseeds), almond or oat milk, and beans (low in phosphorus and gentler on the kidneys)
• Lean animal proteins: Skinless poultry, fish, Salmon, tuna, tilapia, Cod, mackerel, and egg whites (low in saturated fats)
• Avoid high-phosphorus proteins: Processed meats, red meat, organ meats, and fast food

Read More: 10 Benefits of Regular KFT for Monitoring Your Kidney Health

What are the symptoms of protein overload in the kidneys?

If your kidneys are under stress due to excess protein intake, you may experience:

• Fatigue and weakness
• High blood pressure
• Increased thirst
• Brain Fog
• Swelling in hands, feet, or face
• Frequent urination
• Foamy or bubbly urine (indicating protein leakage)

If you experience any kidney-related symptoms or have risk factors like diabetes, hypertension, or a history of kidney disease, consult a doctor for kidney function tests like KFT Test, Creatinine, BUN (Blood Urea Nitrogen), and eGFR (Estimated Glomerular Filtration Rate).

Complications of High Protein Diet

A high-protein diet can offer benefits like muscle building and weight loss, but excessive protein intake over time can lead to several complications, including-

• Proteinuria (Protein in urine)
• Dehydration
• High blood pressure
• Digestive Issues (Constipation or Diarrhea)
• Bone loss & Osteoporosis risk
• Weight gain & metabolic stress
• Higher risk of gout

Also Read: Chronic Kidney Disease (CKD): Symptoms, Causes, Treatment and Prevention

Tips to Balance Protein Intake for Optimal Kidney Health

To maintain kidney health without compromising nutritional needs, follow these tips:

• Calculate your protein needs—The recommended dietary allowance is 0.8 grams per kg of body weight. However, people with kidney disease must consult their doctor about protein intake. 
• Choose High-Quality Protein Sources—To keep your protein levels in check, always choose plant-based protein sources and lean animal protein. Avoid processed meat and fried foods. 
• Balance your protein intake- Combine protein with healthy options to support kidney function. Avoid excessive salt intake, as it increases kidney workload.
• Stay hydrated- Proper hydration helps flush out protein metabolism byproducts like urea and creatinine. Therefore, drink 8–10 glasses of water daily. 
• Take regular Kidney function tests- If you have a high-protein diet, take regular kidney function tests (Creatinine, BUN, and eGFR). Watch for signs of kidney strain, such as foamy urine, swelling, fatigue, or high blood pressure.

Also Read: Discover the Top Foods to Eat for Kidney Health

In Conclusion

Protein intake may vary from person to person's needs, body size, nutritional needs, and health status. Insufficient protein intake may lead to malnutrition, and too much can cause kidney diseases. Therefore, knowing the right amount of protein for proper kidney functioning is important. 

Ask your healthcare professional about the right amount to include healthy protein options in your diet. 

Choose quality protein sources, check your portion sizes, and consume a balanced diet that is nutrient-rich and protein-rich to support your nutritional needs and kidney health. 

FAQ’s

1. Does protein intake affect the kidneys?

Yes, high-protein diets may worsen kidney function in people with existing kidney issues. Therefore, always consult your doctor before starting any new dietary routine. 

2. What is the kidney problem that too much protein can cause?

Proteinuria is the term for too much protein in the urine. It can be a symptom of kidney disorders like nephritis or nephrotic syndrome. 

3. Is plant protein powder bad for the kidneys?

Plant-based protein powder can benefit kidney health, but too much protein can stress the kidneys.