Does your brain age faster than the rest of your body?

Strokes, one of the clearest signs of brain ageing, are occurring at ever younger ages. Between 1990 and 2019, the number of new cases in people under 70 rose by 15%, and the total number of people living with a stroke by 22%. That is a substantial increase in fewer than thirty years. This does not tell us whether the brain ages 'faster' than the body as a whole, but it does show that age-related brain conditions are increasingly less confined to the oldest age groups.

The major risk factors behind this are not unique to the brain: high blood pressure, excess weight, smoking, high blood glucose and air pollution. High blood pressure alone accounts for more than half of all stroke-related disease burden. These are factors that affect the entire body, yet the brain turns out to be particularly sensitive to them.

Chronic stress is a separate story. Stress hormones structurally damage brain regions important for memory and emotional regulation, such as the hippocampus and the prefrontal cortex. Exposure to stress early in life can accelerate the ageing of both the brain and the body. This makes the brain simultaneously vulnerable to stress and the organ from which stress drives processes throughout the body. Whether it therefore ages faster on balance than other organs cannot be stated with confidence on the basis of the available studies.

What the research does make clear is that exercise and social contact help. They reduce chronic stress load and are beneficial for both the brain and the rest of the body. This holds true for people across all age groups.