There’s more than one way to grow old: new research shows at least four types of biological ageing
- Stanford University researchers have found people age along at least four biological ‘pathways’
- It’s hoped the research can define what ageing is and exactly how it progresses
Most of us think we know what ageing looks and feels like. It announces itself with wrinkled skin and grey, thinning hair. It blurs vision, makes joints creaky and, if not rigorously countered, causes things to sag.
But scientists are cataloguing far subtler signs of biological ageing, evident long before hair is lost and skin starts to crinkle.
It’s a story told not just in the body’s organs but in its genes, cells and proteins – even in the bacteria that colonise us. First, one or two molecular processes fall out of whack. Those failures send broader functions off kilter. Sometimes all at once, sometimes gradually, our organs suffer and entire networks – the immune system, for instance – begin to falter.
Understanding how all this happens could allow us to live longer someday. But a nearer goal might produce an even bigger payoff: defining what ageing is and exactly how it progresses may enable us to stay healthy for more of our lives.
Two new pieces of research bring that goal of extending humans’ “healthspan” a bit closer. Both identify biomarkers that help define what it means, at a microscopic level, to age. Both zero in on mechanisms prone to break down as we age – in other words, targets for therapies that could disrupt or delay the ageing process. And both offer some guideposts to measure the effectiveness of elixirs that promise to be (but rarely are) fountains of youth.
