25 Small changes that make a big G difference to YOUR DEMENTIA RISK

The way you choose to live helps define your brain health in later life. Here we list some of the behaviours that scientists believe will keep your head in the game

- IAN TAYLOR Illustration by SAM PEET

There’s a temptation to think that dementia is pre-written into your genes. If you're going to get it, there’s nothing you can do about your fate. Scientists, however, are becoming increasingly confident that this is not the case.

As with many illnesses that don’t arise from accident or infection, dementia risk is a seesaw where genes and lifestyle can both tip the balance. Genetic factors — like which variant of the APOE gene you carry — can certainly increase or decrease your chances, but so too can your diet, activity, behaviours, education and stress levels. In fact, you, rather than your genes, may hold a greater share of the power.

In 2020, researchers at Rush University, Chicago, found that stacking four to five healthy lifestyle factors could lower your risk of dementia by as much as 60 per cent compared to people with zero to one of those factors. The same researchers found, in a separate study, that even in people with a strong genetic predisposition, the life you lead has a large bearing on your long-term brain health.

“APOE4 is a well-recognised and strong genetic risk factor for dementia,” says Dr Klodian Dhana, an associate professor and epidemiologist at Rush who coauthored both papers. “We demonstrated that a healthy lifestyle may still be associated with a slower rate of cognitive decline even among APOE4 carriers.”

Dhana says that debate continues among researchers about the extent to which lifestyle factors can outmuscle our genetics. Still, it’s clear that for many of us, the choices we make can at least influence our chances.

In 2024, an extensive report in The Lancet concluded that “evidence is increasing and is now stronger than before that tackling the many risk factors... reduces the risk of developing dementia.”