London: A new study has blamed modern diet for people`s increasing dental problems.
Researchers say that people soft food diet may actually be causing their jaws to grow too short and small relative to the size of their teeth, meaning their mouths are too crowded,
`The Daily Telegraph` reported.
Comparisons of skulls from 11 different human populations spread across the globe show that those with hunter-gatherer lifestyles grew longer and narrower jaws.
Those with a more modern lifestyle who did not have to chew so much would have put less pressure on the jaw, thus explaining why theirs were shorter and wider, according
to the researchers.
Although almost all the world`s communities now have agricultural rather than hunter-gatherer ways of life, the changes could be seen in skulls from Inuit populations from
Greenland and Alaska within the last 200 years.
In Britain it is likely to have occurred much earlier, with the development of farming coming about 5,000 years ago.
Dr Noreen von Cramon-Taubadel of Kent University, who led the research, said the global nature of the study showed that while features such as skull size are genetic, the variation in jaw size was down to eating habits.
She said: "The jaw is very plastic so depending on your individual behaviour it changes shape during childhood growth and development. There have been suggestions that changing children`s chewing behaviour could have a dramatic effect on the shape of their lower jaw."
The findings have been published in the `Proceedings of the National Academy of Sciences` journal.