How is the long-term, subtle risk from certain herbs characterized in relation to the GFR?

It leads to a gradual decline in GFR over years due to cumulative stress factors.

While known nephrotoxins like *Aristolochia* can cause immediate, catastrophic failure, many other herbs introduce a more insidious risk profile, especially when consumed chronically. This risk involves applying mild but continuous stress to the kidneys over extended periods, such as causing slight, consistent increases in blood pressure or slow, low-grade fluid retention. Because these effects are minor individually, they are often overlooked. However, this continuous imposition on the already diminished reserve capacity of CKD kidneys results in a slow, cumulative erosion of function, manifesting as a gradual decrease in the Glomerular Filtration Rate (GFR) over many years. This insidious decline is difficult to pinpoint to the supplement until significant, permanent damage has already occurred.