Intelligent people are usually healthy as well, according to a study led by researchers at the University of Edinburgh.

Scientists analyzed the genetic data from about 100,000 people held in the U.K. Biobank, and found that the same gene variants that influence a person's health also indicate their ability to think.

When researchers compared each person's mental test data with their genome, they found that some traits linked to disease and thinking skills had common genetic influences.

People who had higher test scores on memory and verbal reasoning were also more likely to be in good health and less likely to possess genes tied to high blood pressure and diabetes. They were also less likely to develop Alzheimer's. Those with higher intelligence scores also tended to be taller and have larger brains.

While those with genes that indicated higher intelligence generally had better health, intelligence did appear to increase the risk of schizophrenia, autism, and bipolar disorder.

The study wasn't the first to link autism with higher intelligence. A 2015 study at the University of Edinburgh that was published in the journal Molecular Psychiatry found that genetic factors associated with autism were linked to higher intelligence in people who did not have the disorder.

"In addition to there being shared genetic influences between cognitive skills and some physical and mental health states, the study also found that cognitive skills share genetic influences with brain size, body shape and educational attainments," said lead researcher Professor Ian Deary.

"The study supports an existing theory which says that those with better overall health are likely to have higher levels of intelligence," said researcher Saskia Hagenaars.

The research was published in published in Molecular Psychiatry.