The kidneys are a pair of bean-shaped organs, each about the size of a fist, situated below the rib cage on either side of the spine. These organs perform many functions to maintain overall health. A common question arises about how their performance might change over a person’s life.
Understanding Kidney Function
The kidneys serve as the body’s primary filtration system, processing blood to remove waste products and excess water. They filter about 120 to 150 quarts of blood daily, producing one to two quarts of urine, which removes toxins.
Beyond waste removal, kidneys maintain a balance of fluids, salts, and minerals like sodium, potassium, and phosphorus in the blood. This electrolyte balance supports nerve and muscle function. The kidneys also produce hormones that regulate blood pressure, stimulate red blood cell production, and help maintain bone health.
How Aging Affects Kidney Performance
A gradual decline in kidney function is a normal aspect of aging. This change often begins around age 30 to 40, though the rate of decline varies among individuals. The kidneys undergo several changes that contribute to this reduced function.
One change is a decrease in the number of functioning nephrons, the filtering units within the kidney. Some nephrons are lost naturally over time, while others become damaged. Blood flow to the kidneys also decreases with age, further impacting their ability to filter efficiently.
The filtering capacity of the glomeruli, networks of blood vessels within the nephrons, also changes. These alterations contribute to a reduction in the overall rate at which blood is filtered. The Glomerular Filtration Rate (GFR) is an important measure of kidney function, indicating how well the kidneys are cleaning the blood. A decline in GFR is often observed as people age.
Beyond Age Other Influences on Kidney Health
While age-related changes contribute to declining kidney function, other factors can accelerate or worsen this process. Chronic diseases are a strong influence, with hypertension (high blood pressure) being a primary cause of kidney damage. Uncontrolled high blood pressure can narrow and harden the arteries supplying the kidneys, reducing blood flow and impairing their filtering ability.
Diabetes is another major contributor to kidney disease. High blood sugar levels over time can damage the small blood vessels in the kidneys, leading to impaired filtration. Cardiovascular disease also negatively impacts kidney health, as a healthy heart is necessary to pump blood effectively to the kidneys.
Certain medications can also affect kidney function. Nonsteroidal anti-inflammatory drugs (NSAIDs) and some antibiotics can be harmful to kidney tissue. Lifestyle factors such as smoking can further compromise kidney health by damaging blood vessels throughout the body, including those in the kidneys.
Strategies for Supporting Kidney Function
Maintaining kidney health as one ages involves several strategies. Staying hydrated is important, as sufficient water intake helps the kidneys flush out waste products effectively. The amount of water needed can vary, but clear urine often indicates good hydration.
Adopting a balanced and kidney-friendly diet also supports kidney function. This includes limiting processed foods, excessive salt, and added sugars, which can contribute to high blood pressure and diabetes. Focusing on fresh fruits, vegetables, and lean proteins can help reduce the workload on the kidneys.
Effective management of existing chronic conditions is important. Controlling blood pressure and blood sugar levels through medication and lifestyle adjustments can slow the progression of kidney damage. Regular monitoring by a healthcare provider ensures these conditions are well-managed. Avoiding substances known to be toxic to the kidneys is also important. Regular medical check-ups, including kidney function tests, allow for early detection of any changes and timely intervention.