Maintaining optimal kidney function is crucial for overall well-being, as these vital organs play a central role in filtering waste products, regulating electrolytes, and managing fluid balance in the body. One of the lesser-known but significant markers of kidney function is Cystatin C. This small protein, produced by almost all cells in the body, serves as an important indicator of how well your kidneys are functioning. When levels of cystatin C rise, it often signals that your kidneys may not be working as efficiently as they should. In this blog, we’ll explore what cystatin C is, how it relates to kidney health, and how you can easily monitor your levels with a blood test from Youth Revisited, an online UK-based blood testing service.

What is Cystatin C?

Cystatin C is a protein produced by cells throughout your body. It plays an essential role in regulating the activity of enzymes called cysteine proteases, which are responsible for breaking down proteins in the body. However, when it comes to monitoring kidney function, cystatin C’s most important role is how it’s filtered through the kidneys.

Unlike other markers of kidney function, such as creatinine, cystatin C is not influenced by muscle mass, age, gender, or diet, making it a potentially more reliable indicator of kidney function, especially in people who have varying body compositions. Since cystatin C is produced at a constant rate by all nucleated cells in the body, the level in the blood should remain fairly steady if the kidneys are functioning properly. However, if kidney function begins to decline, cystatin C accumulates in the bloodstream, leading to higher levels that can be detected in a blood test.

How Does Cystatin C Relate to Kidney Function?

The kidneys are responsible for filtering waste products from the blood, and when they are not functioning optimally, waste products like cystatin C accumulate in the bloodstream. Therefore, high levels of cystatin C can be an early warning sign of impaired kidney function. This is particularly useful in detecting kidney disease in its early stages, as cystatin C levels tend to rise earlier than traditional markers such as creatinine.

Many doctors use cystatin C testing as a supplemental or alternative measure to creatinine testing. While creatinine is a widely used marker of kidney function, its levels can be affected by factors such as muscle mass and diet. Cystatin C is less likely to be influenced by these variables, providing a potentially more accurate reflection of kidney health, especially in people with unusual body compositions or those on specific medications.

When Should You Test for Cystatin C?

Cystatin C test can be particularly beneficial for:

  • Individuals at risk of kidney disease: If you have diabetes, hypertension, or a family history of kidney disease, monitoring your cystatin C levels can help detect potential issues early.

  • People with abnormal creatinine levels: If your creatinine levels are inconsistent or difficult to interpret due to factors like muscle mass, cystatin C can provide a clearer picture of kidney function.

  • Those undergoing medical treatment that affects kidney function: Certain medications, like those for cancer or immunosuppressants, can put strain on the kidneys, making regular cystatin C testing important.

Ultimately, if your doctor recommends a kidney function test, it may involve measuring both cystatin C and creatinine to get a fuller picture of your kidney health.

Youth Revisited: Convenient Blood Testing Services in the UK

At Youth Revisited, we believe in making health monitoring easy, accessible, and private. Our online platform allows you to book blood tests in the UK from the comfort of your home, offering a convenient solution for individuals who want to stay on top of their health without the hassle of long waits, unnecessary paperwork, or complicated procedures.