Over centuries, humans have been growing taller.
Now scientists think they have the answer as to why, and the phenomenon is explained by a sensor in the brain.
The discovery made by UK scientists could inform the development of new drugs to help delayed growth in humans and boost muscle mass.
Throughout history, as nutritional health has improved, so have people’s growing potential.
In the UK the average height rose by 3.9in (10cm) during the 20th Century, and in other countries it was 7.8in.
In South Korea, the average height shot up as the area became increasingly developed and less financially dire – naturally, this has played a role in the nation becoming taller.
It has long been known that better nutrition means people grow taller quicker. In parts of the world with less affluent development, people have grown taller by only small amounts.
It was also already known that signals from food reach a part of the brain called the hypothalamus.
This part can instigate growth – now the brain receptor responsible for that has been found.
The study, published in Nature, identified the receptor MC3R which links food, sex development and growth.
Research was carried out by the University of Cambridge, Queen Mary University of London, University of Bristol, University of Michigan and Vanderbilt University.
Prof Sir Stephen O’Rahilly, study author from Cambridge, says: ‘It tells the body we’re great here, we’ve got lots of food, so grow quickly, have puberty soon and make lots of babies.
‘It’s not just magic – we have the complete wiring diagram for how it happens.’
They also found that when this receptor doesn’t function at it’s optimum, people can be shorter and start puberty later.
Using the genetic make-up of 500,000 volunteers, it was confirmed that children with gene mutations that affect the brain receptor were all shorter and lighter in weight than others.
It reveals the receptor affects humans early on into growth.
The research team found one person with rare mutations in both copies of the gene for MC3R – this individual was very short and began puberty after reaching the age of 20.
Scientists also looked at mice to see if the same issue occurs the animals.
Finding the same pathway, this discovery was confirmed to be true for not just humans.
It’s believed this research could help children with hindered growth and delayed puberty, along with those who have chronic illnesses that lead to weakened muscle.
Prof O’Rahilly said: ‘Future research should investigate if drugs that selectively activate the MC3R might help redirect calories into muscle and other lean tissues, with the prospect of improving the physical functionality of such patients.’
Credit: Original article published here.