An unprecedented window into how diseases take hold years before symptoms appear

> What UK Biobank is revealing, scan by scan and layer by layer, is that disease doesn’t arrive out of nowhere. It accumulates quietly, shaped by genes, environment, and habits.

I think that is already known for a while. It's called functional reserve, and was a big topic in HIV patients (and then again for SARS-CoV-2).

Like people with higher cognitive capabilities will be protected by those a bit longer before onset of HIV-associated neurocognitive disorder (or even dementia).

Same for kidneys: They have a functional reserve that you are born with gets used up during life, until it is gone. Acute kidney disease treatment is aimed at preserving whatever little function is left.

I am a 61 year old guy. I've never been overweight, never smoked, I've never been drunk and drink only infrequently, and have been fitter than average ... sometimes very fit. A few years ago I decided to make an undirected kidney donation. I thought I'd be a slam dunk. Everything was great, except my eGFR (estimate granular filtration rate) was 73, and for many people it is more like 110, which disqualified me, as after donating my number would get cut in half, putting me at some risk.

So I pulled up blood work results going back 15 years that I had records for and found that 73 was my high score! It typically was mid 60s, with a low of 61. I have no idea why it is so low. Anyway, this is the reason I'm relating this story. It seems odd that my kidney function has gone up. It wasn't just a fluke -- I've had bloodwork done at least five times since then and I'm always in the mid 70s now.