Glomerular Filtration Rate, or GFR, is a measure of kidney function, indicating how well these organs filter waste products from the blood. This continuous work is important for maintaining overall health by balancing the body’s internal environment and removing toxins.
Understanding Your GFR
GFR is commonly estimated (eGFR) using a blood test that assesses the level of creatinine, a waste product from muscle wear and tear. The eGFR calculation also considers factors such as age, sex, and body size. In some cases, cystatin C levels may also be used, as they are less affected by muscle mass, age, or diet.
For healthy young adults, a normal GFR range is approximately 80-120 mL/min/1.73 m², although values vary by age and sex. GFR naturally declines with age, even in individuals without kidney disease. For instance, the average eGFR for adults aged 20-29 is around 116 mL/min/1.73 m², decreasing to about 75 mL/min/1.73 m² for those 70 and over.
A GFR below 60 mL/min/1.73 m² may indicate kidney disease, while a GFR of 15 mL/min/1.73 m² or lower can signify kidney failure. Early detection of a declining GFR allows for timely intervention, helping to slow or prevent the progression to advanced kidney disease. Monitoring GFR is important because changes can signal kidney damage and guide treatment strategies.
Lifestyle Approaches for Kidney Health
Adopting specific lifestyle changes can support kidney function and potentially help stabilize or improve GFR. A balanced and kidney-friendly diet is a primary focus, emphasizing whole foods while limiting processed items. Reducing sodium intake, ideally aiming for less than 2300 mg per day, helps manage fluid balance and blood pressure.
Managing protein intake is also important, as the body produces waste products from protein that the kidneys must filter. Your doctor or a dietitian can help determine the appropriate amount and type of protein for your needs. Consuming more fruits and vegetables can support kidney health by aiding in weight management and blood pressure control.
Adequate hydration is important for kidney function, as water helps the kidneys remove waste from the blood and maintain open blood vessels. While drinking enough water is generally beneficial, individuals with advanced kidney disease may need to limit fluid intake, as damaged kidneys struggle to remove excess water. The color of urine can indicate hydration status; straw-colored or paler urine suggests adequate fluid intake.
Regular physical activity benefits overall health, including kidney health, by improving cardiovascular health and helping to control blood pressure and blood sugar levels. Moderate-intensity activities like walking, cycling, or swimming for at least 150 minutes per week are often recommended. Exercise helps reduce factors that can strain the kidneys.
Maintaining a healthy weight also reduces the burden on the kidneys, as obesity is a risk factor for kidney disease. Avoiding harmful substances, such as tobacco and excessive alcohol, is also important. Smoking introduces chemicals that impair kidney function by narrowing blood vessels and reducing blood flow to the kidneys.
Medical Management and Monitoring
Managing underlying health conditions plays a role in maintaining GFR and kidney health. Conditions like high blood pressure, diabetes, and heart disease can significantly impact kidney function. High blood pressure can narrow blood vessels, reducing blood flow to the kidneys and affecting GFR.
Diabetes can also damage the kidneys over time, and managing blood sugar levels is important for kidney protection. Heart disease and kidney disease are closely linked, with issues in one often affecting the other. Medications prescribed for these conditions are important for stabilizing kidney function.
Regular GFR monitoring by a healthcare professional is important, especially for individuals with risk factors for kidney disease. These risk factors include diabetes, high blood pressure, a family history of kidney disease, and being over 50 years old. Early detection of declining GFR allows for timely medical intervention and adjustments to treatment plans.