FRIDAY, Dec. 14, 2012 (HealthDay News) -- Elderly black people who sometimes went hungry as children had slower mental decline than those who always had enough to eat, a new study finds.
"These results were unexpected because other studies have shown that people who experience adversity as children are more likely to have problems such as heart disease, mental illness and even lower cognitive [brain] functioning than people whose childhoods are free of adversity," Lisa Barnes, a cognitive neuropsychologist in the Rush Alzheimer's Disease Center at Rush University Medical Center, said in a medical center news release.
The study included more than 6,100 people, average age 75, in Chicago. The participants were asked about their health as children and about other aspects of their childhood. Then, every three years for up to 16 years, they underwent tests to measure any changes in their mental abilities and skills.
The nearly 6 percent of black people who said they sometimes, often or always went without food as children had a one-third slower rate of mental decline during the study than those who said they rarely or never went hungry, the investigators found.
The roughly 8.5 percent of blacks who said they were much thinner at age 12 than other children their age also had a one-third slower rate of mental decline than those who said they were about the same size or heavier than other children their age.
There was no relationship between childhood hunger and mental decline in whites, according to the study in the Dec. 11 issue of the journal Neurology. This may be because so few white people in the study reported hunger or other types of adversity in childhood.
"Researchers are not sure why childhood hunger could have a possible protective effect on [mental] decline," said Barnes, who is also an associate professor in the neurological and behavioral sciences departments at Rush University. "One potential explanation for the finding could be found in research that has shown that calorie restriction can delay the onset of age-related changes in the body and increase the life span."
Another explanation could be a selective survival effect, she noted.
"The older people in the study who experienced childhood adversity may be the hardiest and most resilient of their era; those with the most extreme adversity may have died before they reached old age," Barnes said.
While the study found an association between childhood hunger and less mental decline in older adults, it did not prove cause-and-effect.
The Society for Neuroscience has more about healthy brain aging.