Three Things Nobody Told Me About My Knees Until I Was 62

Cartilage has no nerve supply. None. It is physically incapable of hurting.

I had to have that said twice before it landed. The tissue everybody calls “the problem” has no way of telling you it's in trouble.

So what had I been feeling every morning for eleven years?

Everything around it. As the cushion thins, the bone underneath takes load it was never shaped for. Bone has nerves. It responds — swelling inside the marrow, small fluid-filled cysts, inflammation in the lining of the joint. That is the ache. That is what wakes you on the stairs.

Which means the pain is not the wear. The pain is the reaction to the wear, arriving late, from a different tissue.

It also explains the thing that had baffled me for years — why my worse-looking knee was the one that hurt less, and why some mornings were fine and some weren't, with no pattern I could find.

This is the one that made me put my cup down.

Cartilage has no blood running to it. It cannot pull nutrients out of your bloodstream the way muscle or skin does. It is a sealed cushion between two bones.

It feeds a completely different way: it drinks the fluid inside the joint, like a sponge. That fluid is the only delivery route there is.

So when I swallowed a capsule every morning for eleven years, it dissolved, it entered my blood, and then it needed to do a second thing — cross out of the blood into the joint fluid. Most of what I took never did. It circulated, and it left.

The physiotherapist put it in one sentence and I've not forgotten it since:

“You didn't fail the supplement. The supplement never made the jump.”

Eleven years of blaming winter, my weight, my age, being on my feet all day. The pills weren't weak. They were arriving in the wrong room.

A sponge sitting in liquid doesn't absorb much. A sponge you squeeze does.

Cartilage is the same. Every step compresses it, pushes the old fluid out, and lets fresh fluid draw back in as the load releases. Movement is the pump. Without it, the delivery route barely runs.

Now hold that next to what I'd been told for a decade, by well-meaning people: take it easy, protect the knee, don't overdo the walking.

Here is what the research actually shows. Recreational runners have roughly three times lower rates of knee and hip osteoarthritis than people who don't run. Competitive runners, lower still. Running appears to thicken knee cartilage rather than wear it away.

I'm not telling you to go running. I'm 62 and I have no intention of it.

I'm telling you that the instruction to sit still was switching off the only pump the tissue has — and I followed it carefully for years, believing I was being sensible.

The reason nobody had ever bothered to explain any of the above to me, I think, is that it didn't seem to matter. Cartilage wears out, cartilage doesn't grow back, manage the pain, come back in six months.

That last part is being actively reconsidered. National Geographic ran it plainly this year: doctors have long said cartilage can't regenerate, and they're now rethinking that. Researchers at Stanford Medicine published work on reversing cartilage loss in aging joints; cartilage taken from knee replacement surgery produced new tissue in the laboratory.

Now — I want to be completely straight with you about what that is and isn't.

That is laboratory and early-stage research. It is not a supplement, it is not on a shelf, and nothing you can buy today, including the product I take, does what those researchers did. Anybody who tells you otherwise is lying to you.

What it changed for me was smaller and more useful than that.

“It can't come back” is the belief that made me stop trying to feed the joint at all. I wasn't managing it. I was writing it off, one flight of stairs at a time, and calling that being realistic.