An inflammatory opinion

It is obvious that living things get old and die; wear and tear affects everything in the end, no matter how carefully it is nurtured, so it stands to reason that one day everyone of us must accept his or her time is up.

Yet modern researchers in longevity push back against such fatalism; unlike a car or a new pair of shoes, living things repair themselves as they go. Cuts heal, bones remineralise, old cells are cleared away and new ones sprout. Even your brain, whose cells were once thought to be fixed early in life, is known to make new neurons as it needs them. So the real question is why such processes falter. After all, as long as they keep working, then so do you.

There are many theories, but a stand-out one, widely accepted in the medical community, is that the weak point in the metabolism of long-lived things is the immune system. The immune system is your internal police force. It is a complex collection of proteins (antibodies), white blood cells, and organs like your spleen and tonsils, which keep a watching brief over your bodily integrity. As soon as something goes wrong – a bacterium gets through your skin, your ankle turns and rips its ligaments, or any one of a thousand other mishaps – the squadrons of containment and repair flow to the site through your blood vessels and restore order. Often you don’t even know it is happening. Unfortunately, the older you get, the less friendly these powerful forces become. Years of life mean they have been called into action many, many times, and eventually, around middle age, they become permanently stimulated. Just quietly – you don’t feel unwell – but a low-grade permanent level of inflammation settles down as the new normal for your blood vessels and vital organs.

This silent smoldering inflammation is what heart attacks, strokes, cancer and some forms of dementia (even depression) arise from. These diseases, the most feared consequences of the latter years of life, are not random malfunctions. They all arise from this quiet, ubiquitous, age-related shift in the settings of your immune system.

So far, so conventional. No doctor disagrees. Where the story gets exciting – and controversial – is what you can do to stop it happening. My book The Internal Flame sets out in easily digestible form the detail and the science of age-related inflammation and its role in provoking big diseases. It also discusses at length the way certain lifestyle choices can slow it all down and fend off the big events for years. The star of these options is the phenomenon known as “functional food”. Functional food is food that goes beyond ordinary nutrition and delivers molecules that manipulate your immune system, like drugs do. Some of these options are well known to health-conscious people, like blueberries and dark chocolate. Others are obscure: ever fancied olive leaves, or tree sap?

It is a new concept, and evolving, but that is what makes it interesting. All health-conscious people know the basics of good eating. Functional food is the next step. My book argues that highly specialised dietary choices could be the way of the future in keeping our immune systems in balance, and extending our lives as far as they can go.