Massachusetts - Clever children may be less likely to go on to develop serious disease in later life compared with their less intelligent peers, research in America suggests.
A study in the United States found that conditions such as heart disease, diabetes, asthma, cancer, arthritis and stroke were more common among adults who scored lower in IQ tests as youngsters.
The researchers, writing in the Journal of Epidemiology and Community Health, concluded that childhood intelligence could be an early indicator of future health.
The team, from the Harvard School of Public Health, based their findings on a study of 633 people living in Providence, Rhode Island.
This group was part of a larger study monitoring 50 000 pregnancies across the US up to the age of seven, when they completed a comprehensive IQ test.
Between the ages of 30 and 39 the group was asked if they had any serious illnesses, also including bleeding ulcers, tuberculosis and hepatitis.
Other factors which can affect intellectual development - such as low birth weight and social and economic background - were also taken into account but did not unduly influence the results, the researchers said.
The team, led by Dr Laurie Martin, found that the overall prevalence of serious disease was low.
But they noted that higher intelligence scores at the age of seven were linked with a lower overall risk of serious illnesses.
Those with lower IQ were also more likely to report having several serious illnesses.
The pattern was not limited to any particular disease, but applied across them all generally, according to the report.
The researchers found that every extra 15 points on intelligence score at the age of seven cut the chance of illness as an adult by a third.
They concluded: "People with lower cognitive performance in childhood are at increased risk for serious illness in adulthood, suggesting that childhood cognitive performance is an early determinant of adult health."
The reasons for the health differences were not clear, but the authors suggested that intelligence may reduce the likelihood of risky and unhealthy behaviours.
"There is evidence that health behaviours such as smoking, physical fitness, diet and alcohol are associated with cognitive performance," they said.
The researchers also suggested that intelligence may help people better navigate the healthcare system to make the most of what is on offer.
They added: "Sense of control may also contribute to the association between childhood IQ and adult health.
"People with a higher level of cognitive performance may feel more in control and have less of a physiological response to stressors, resulting in less wear and tear on the body and ultimately better health." - Sapa-DPA