Inflammation and Ageing: What's the Link?

What chronic inflammation actually is

Acute inflammation is short, sharp and self-limiting. The immune system dispatches white blood cells to the site of the damage (like a cut, wound or insect bite) to start the healing process. When the healing is complete, the immune cells ‘stand down’.

Chronic inflammation is none of those things. It's a persistent, low-level activation of the immune system that researchers have linked to the pathophysiology of most of the conditions associated with growing older, from cardiovascular disease and type 2 diabetes to osteoarthritis and several neurodegenerative conditions.

A good part of where it comes from is explained by what happens inside cells as the body ages: billions of cells die and get cleared away every day. Some, however, become senescent instead, meaning they stop dividing but don't get removed.

These senescent cells don't sit quietly; they secrete inflammatory chemicals that damage the tissue around them, and the older someone gets, the more of these cells tend to accumulate. It’s something you likely won’t notice day-to-day but it does have major longer term implications for healthy ageing. 

The oxidative stress connection

Chronic inflammation rarely shows up alone. It often comes with oxidative stress, the damage done by free radicals, unstable molecules thrown off by ordinary metabolism, pollution, UV exposure, stress. The two feed each other: inflammatory chemicals generate more free radicals, free radical damage provokes more inflammation, and round it goes. Left alone, that loop just keeps tightening.

Age doesn't help. The immune system gets sloppier at precisely the job of switching itself off once it's finished, a decline researchers call immuno-senescence. So, inflammation that would once have resolved in a few days starts to linger instead.

Why this matters beyond a sore joint

What makes this worth caring about is how far it reaches. A sprained ankle stays in the ankle. Chronic inflammation doesn't respect boundaries like that. It's turned up in arterial stiffness, in the slow loss of muscle known as sarcopenia, in cognitive decline, in the "wear and tear" most people blame on simple old age without realising inflammation is doing a fair bit of the wearing.

The system built to protect the body ends up, quietly, working against it.

Even centenarians carry some degree of inflammageing, so eliminating it isn't really the goal of longevity and probably isn't possible anyway. Keeping it as low as it reasonably can go, for as long as possible, is. It's one of several traits that separate people who achieve healthy ageing from those who don't.

What actually helps

Diet is one of the few genuinely powerful levers here. The ATTICA Study is the clearest evidence1 people who stuck closely to a Mediterranean-style diet showed meaningfully lower C-reactive protein and interleukin-6, Thes are two of the body's main inflammatory markers, along with lower white blood cell counts and fibrinogen. (And your doctor can measure them in a blood test)

A lot of that inflammation lowering effect seems to come down to polyphenols, the compounds behind the colour in so much of the Mediterrananen diet. They work two ways: propping up the body's own antioxidant defences and adding antioxidants directly through food. Oily fish and good olive oil calm inflammatory signalling. Berries, leafy greens and colourful vegetables bring a spread of polyphenols rather than just one type.

Nuts, seeds and wholegrains feed the gut bacteria that help keep immune regulation on track. Processed and refined sugar does more or less the opposite of all that. None of it works as well on its own as it does together, which is really the argument for the nutritional case for the Mediterranean Diet rather than chasing any single ingredient.

The rest of the picture  

Food isn't the whole story. Movement, decent sleep, keeping weight in a sensible range, all of it dampens chronic inflammation too, partly because fat tissue itself pumps out inflammatory signals.

None of this is coincidence: the daily habits that support healthy ageing more broadly overlap heavily with what inflammation research recommends, because underneath, they're often the same mechanisms. The broader essentials of staying healthy as you age cover how it all fits together.

None of this cures anything. But diet and lifestyle do seem to meaningfully shift how much inflammation builds up over time, and with it, how well the body copes later on. It's a slow process. Dealing with it works best the same way, rather than treating it as something to fix once it's already causing trouble.