Human brain / AIGrowing up in poverty may make the brain grow old faster than even a cancer diagnosis would, a new Kenyan study by Aga Khan University has found.
The study showed people who faced hunger as children or lived in poor households were more likely to have memory and thinking problems later in life than people living with cancer.
Some cancer treatments, especially chemotherapy, can sometimes affect memory, attention and thinking.
Researchers said the findings challenge the common belief that diseases such as cancer are the biggest threats to brain health in old age.
The three-year study, called Brain Resilience Kenya, followed more than 404 adults aged 35 years and above from different backgrounds across Kenya.
Scientists wanted to understand why some people keep sharp minds as they grow older, while others struggle with memory, learning and decision-making.
The researchers looked at many parts of a person's life. They studied brain scans, blood samples, memory tests, sleep patterns and physical activity.
They also asked people about their childhood, education, health, family support and living conditions.
The findings showed a person's brain health starts being shaped very early in life.
Children who experienced hunger or severe poverty were more likely to have poorer brain health decades later.
On the other hand, people who grew up feeling safe, stayed in school longer and had strong social support were more likely to keep healthy brains as they aged.
The study found that childhood hunger and poverty were among the strongest predictors of how well a person's brain would perform later in life.
Researchers also found something surprising about cancer.
There was no evidence that people with breast or prostate cancer performed worse in memory and thinking tests than people without cancer. Instead, poverty and life experiences had a much stronger effect on brain health.
The study also looked at people caring for relatives with cancer.
These caregivers often showed signs of higher stress levels and poorer health than the patients themselves.
Speaking during the release of the findings in Nairobi, Prof Zul Merali, founding director of the Brain and Mind Institute at Aga Khan University, said the study should change how society thinks about resilience.
"This study reminds us that resilience is not something we are simply born with. It can be nurtured by families, strengthened by communities, supported by health systems and encouraged through public policy," Merali said.
"Understanding the factors that help people adapt, recover and thrive despite life's challenges creates healthier communities and better opportunities for healthy brain ageing."
The findings were shared during a community workshop and health fair supported by Dartmouth University.
The meeting brought together study participants, community health promoters and residents to discuss ways of protecting brain health throughout life.
The researchers said good brain health depends on much more than medical treatment.
Heart health, education, friendships, proper nutrition and safe communities all play important roles in keeping the brain healthy.
Higher blood sugar levels were linked to a greater chance of memory and thinking problems, while people with higher levels of good cholesterol had healthier brains.
Regular exercise and controlling blood pressure and diabetes were also linked to better brain health.
Prof Mansoor Saleh, one of the study leads, said doctors must look beyond disease when caring for patients.
"These findings remind us that brain health is influenced by more than disease alone. We found that people diagnosed with cancer had more brain resilience compared to their caregivers, showing the great impact support has in advancing resilience," Saleh said.
"Alongside treating cancer, we must support patients' overall wellbeing by promoting heart health, mental wellbeing and strong social support to help improve quality of life and healthy ageing."
The researchers also discovered that sleep and physical activity matter.
Participants in the study took more than 431 million steps during the research period and slept for an average of almost seven hours each night. More movement was linked to better health and wellbeing.
Education also emerged as one of the strongest protections for the brain.
People with higher levels of education were more likely to remain mentally sharp as they aged. Researchers believe education helps the brain build what scientists call "cognitive reserve", which allows it to cope better with stress and disease later in life.
Dr Karen Blackmon, a consultant neuropsychologist and co-principal investigator of the study, said the findings show biology alone does not determine a person's future.
"Advanced brain imaging and cognitive assessments gave us valuable insights into how the brain responds to life's challenges and what supports healthy brain ageing and resilience"
"Combined with participants' lived experiences, these findings show that resilience is shaped by both biology and environment, providing important evidence to guide future interventions that promote cognitive health."
The researchers hope the findings will help shape future health programmes and policies in Kenya and across Africa.
