Does your brain age faster than the rest of your body?
Whether your brain ages faster than the rest of your body varies from person to person, but the consequences are significant: a biologically old brain increases the risk of Alzheimer's more than threefold. Keep an eye on your blood pressure, sleep and lifestyle, as these have the most demonstrable influence on brain ageing.
The brain does not age at the same pace as the rest of the body, but whether it ages faster depends strongly on the individual. Research involving more than 50,000 people shows that biological ageing is not a gradual process: there are acceleration peaks around the ages of 41, 60 and 67. For the brain, peaks of accelerated biological change are visible at 57, 70 and 78, with each peak driven by its own underlying processes, such as inflammation or a decline in repair capacity.
Almost one in five people has one organ that is biologically ageing considerably faster than the rest of the body. The brain and blood vessels stand out in particular: accelerated ageing of the brain or blood vessels predicts the development of Alzheimer's disease just as strongly as the best blood test currently available for that condition. People with a biologically 'old' brain have more than three times the risk of developing Alzheimer's over the following 17 years. That effect is comparable to carrying one copy of the APOE4 gene, the best-known genetic risk factor.
The reverse is also true: a biologically young brain offers strong protection. People with both a young brain and a young immune system have more than half the risk of premature death compared with people in whom both organs are biologically old. Of all eleven organs studied, the brain and the immune system are the two strongest protectors. Other organs do not show this pattern to the same degree.
Brain ageing begins early in life and is accompanied by measurable volume loss, a thinning cerebral cortex and the breakdown of nerve pathways. These are in themselves normal processes, but they lie on a sliding scale towards diseases such as Alzheimer's and Parkinson's. Age is the greatest risk factor for neurodegenerative conditions: one in ten people over 65 has Alzheimer's, and the probability continues to rise with the years.
Whether anything can be done about it remains largely unanswered. A compound called urolithin A, which gut bacteria produce from pomegranate and nuts, improves muscle function in older adults in clinical studies and protects the brain in animal research. For the brain, however, there are as yet no clinical results in humans, and several authors of that research have commercial ties to the manufacturer. Concrete recommendations for slowing brain ageing cannot at this point be derived from the available studies.
All claims are based on associational research (cohort and proteomic studies). No RCTs on interventions specifically targeting brain ageing. Plasma protein models are promising but have not yet been widely validated in clinical practice.
How do you keep your brain healthy as you age?
Combining more physical activity with staying mentally active and eating a diet low in sugar and higher in omega-3 fatty acids currently gives you the best chance of a healthy brain. Spermidine and new insights into how the brain cleans itself are, for now, interesting developments to follow rather than actionable advice.
What do immune cells in your brain do during ageing?
Microglia play an active role in brain ageing through fat build-up and energy shortage, but most of the evidence still comes from animal studies. There are no human treatments yet, so if you have concerns about memory problems, discuss them with your doctor.
What does excess weight do to your brain in the long run?
Excess weight harms your brain in multiple ways at once: less brain tissue, weaker connections and a higher risk of dementia. Exercise combined with diet appears to be able to partly reverse this, so losing weight is good for your brain too.
Do your brains really shrink as you get older?
Your brain does indeed shrink with age, particularly in areas involved in memory and planning. High blood pressure accelerates that process, while exercise and cognitive effort strengthen your brain's compensatory activity.
Does speaking a second language or making music protect the brain from ageing?
Speaking two languages pushes the first symptoms of dementia back by an average of three to seven years, though it does not prevent dementia altogether. Making music shows preliminary indications of brain changes in healthy older adults, but the evidence is still too thin for firm conclusions.
What does smoking do to your brain as you age?
Smoking accelerates brain ageing and increases the risk of dementia. Quitting smoking is one of the best-supported steps you can take to keep your brain healthy for as long as possible.