Risk of dementia can be lowered through
movement, adequate sleep, physical activity. The less sedentary the lesser the
risk, according to a study.
Dementia is a main cause of death in older
people. Around 55 million people worldwide live with it. By 2050, the number is
likely to soar, mostly in poorer countries. Caring for dementia is very costly
for families and society, so it’s important to find health problems that can be
prevented to lower the risk.
A report published in PLOS One shows
that habits such as regular physical activity, good sleep, and less sitting may
lower the risk of dementia. Identifying preventable risk factors is crucial.
Physical
activity has long been linked to better brain health.
Exercise reduces inflammation, improves heart health, and boosts blood flow to
the brain. It also increases protective molecules like brain-derived
neurotrophic factor (BDNF). In this review of 49 studies, about half showed
significant benefits, and pooled data suggested a 25% lower dementia risk among
active adults over 50. The 2024 Lancet Commission estimated that 2% of
new dementia cases could be tied to low activity in midlife.
Sedentary
behavior, such as sitting for long hours, is linked to
higher cardiovascular and metabolic risks. Only three studies were included,
but they found dementia risk was 27% higher in people sitting eight or more
hours daily compared to those sitting less.
Sleep plays a key role too. Both short sleep (less than 7 hours) and long
sleep (more than 8 hours) were linked to higher dementia risk—18% and 28%
respectively. Too little sleep may impair the brain’s waste-clearing system,
while long sleep may worsen chronic conditions or signal early disease.
The study was based on large, diverse
populations and long follow-up periods, which improve reliability. However,
limitations exist: many studies relied on self-reported behaviours, showed
variability in results, and carried risks of bias. Reverse causation—where
early dementia symptoms affect lifestyle—remains possible.
Overall, the findings suggest that adults
who stay active, avoid long sitting, and sleep 7 to 8 hours nightly may reduce
their dementia risk. These behaviours are interconnected and influenced by
other health conditions, making their combined effects complex. Since dementia
develops over many years, more long-term studies in middle-aged populations are
needed to confirm these links.
Public health strategies could encourage
walking groups, workplace movement breaks, and better access to safe spaces for
exercise. While the evidence is not yet strong enough for firm guidelines,
adopting healthy daily routines may help delay or prevent dementia in many
people.
