People don't grow up until their 30s

Have you ever been told to "grow up" in your 20s or need an excuse as to why you still find cat videos on the internet really funny?

Well now you might have an official reason as to why you're not acting like a mature adult.

People don't become fully "adult" until they're in their 30s, according to brain scientists, BBC New reports.

Currently, the Serbian law says you become a mature adult when you reach the age of 18.

Scientists who study the brain and nervous system say the age at which you become an adult is different for everyone.

Research suggests people aged 18 are still going through changes in the brain which can affect behavior and make them more likely to develop mental health disorders.

– What we're really saying is that to have a definition of when you move from childhood to adulthood looks increasingly absurd – Professor Peter Jones, from Cambridge University, said.

– I guess systems like the education system, the health system and the legal system make it convenient for themselves by having definitions – he adds.

When you reach 18, you can vote, buy alcohol, get a mortgage and are also treated as an adult if you get in trouble with the police.

Despite this, Professor Jones says he believes experienced criminal judges recognize the difference between a 19-year-old defendant and a "hardened criminal" in their late 30s.

– There isn't a childhood and then an adulthood. People are on a pathway, they're on a trajectory – he added.

Cambridge University

Peter Jones

adulthood

switch from childhood to adulthood