BBC News: The brain sensor discovery behind humans getting taller

[John Mac]

The puzzle of why humans are growing taller and reaching puberty earlier than ever before can be explained by a sensor in the brain, scientists say.

The average height in the UK rose by 3.9in (10cm) during the 20th Century, and up to 7.8in in other countries, as nutritional health improved.

But exactly how this happens has never been understood.

The discovery could lead to drugs to improve muscle mass and treat delayed growth, UK researchers say.

Scientists have known for a long time that humans with easy and reliable access to food tend to grow taller, and evolve into adults more quickly.

In South Korea, for example, adult height has rocketed as the nation transformed from a poor country to a far more developed society. Yet in parts of South Asia and Africa, people are only slightly taller than 100 years ago.

It's known that signals reach a part of the brain called the hypothalamus, telling it about the body's nutritional health, and triggering growth.

This new study, published in Nature, and led by researchers from the University of Cambridge alongside teams from Queen Mary University of London, University of Bristol, University of Michigan and Vanderbilt University, has discovered the brain receptor behind that process.

It's called MC3R and is the crucial link between food and sex development and growth.

"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," said Prof Sir Stephen O'Rahilly, study author, from Cambridge.

"It's not just magic - we have the complete wiring diagram for how it happens."

https://www.bbc.co.uk/news/health-59140359

 

[InitialConditions]

A 10cm increase over just 100 years seems quite remarkable.

 

[Mithriel]

It does not explain the onset of puberty in very young girls from as young as 5 years old.

Thirty years ago they spoke of feminised fish due to the amount of hormones in the water after the contraception pill became widespread and the use of hormones in farming and good old industrial pollution.