People with a higher IQ are more likely to be vegetarian, psychological research finds.

In fact, vegetarians could be up to 10% more intelligent than red meat eaters, according to some studies.

A higher IQ is also seen among those who describe themselves as vegetarian, but also eat chicken and fish.

The conclusion comes from a survey of 8,170 men and women whose IQ was tested when they were 10-years-old.

By age 30, 4.5% had become vegetarian, of these 2.5% were vegan and 33.6% said they were vegetarian, but still ate chicken and/or fish.

People with higher IQs at age 10, the analysis showed, were more likely to be vegetarians at age 30.

There was no difference between stricter vegetarians (ovo-lacto vegetarians) and those who ate some chicken and/or fish as well.

The findings could help to explain why more intelligent people are also healthier, since a vegetarian diet is better for the heart and for maintaining a healthy body mass.

Does money and class explain it?

Part of the link between IQ and vegetarianism was explained by social status and education.

In other words, people of higher social class are more likely to be intelligent and more likely to be vegetarian anyway.

Still, even when these two factors were accounted for statistically, the relationship between vegetarianism and IQ remained.