People used to be particularly dissatisfied with their lives in middle age, creating a " unhappiness hump " between the happier periods of youth and old age—but this is no longer the case.

This notorious peak has now disappeared, not because people are happier in middle age, but because young people are more unhappy than before, said Alex Bryson of University College London.

"We found that stress increases among most people under the age of 40 and grows much faster the younger you are. So we are seeing an increase in stress over time, with younger people becoming increasingly stressed," he explained.

Previous studies based on data from 145 countries suggest that people are happiest before the age of 30 and after the age of 70, with unhappiness peaking around the age of 50. Similar trends seem to apply even to orangutans and chimpanzees.

But Bryson and his colleagues noticed that the unhappiness hump seems to have disappeared, based on data from national mental health surveys in the US, which involved 10 million adults from 1993 to 2024, and in the UK, which surveyed 40,000 households from 2009 to 2023.

To understand whether this is true on a global scale, researchers turned to data from Global Minds, a mental health study conducted since 2020 among nearly 2 million people in 44 countries, including the US and the UK. They found that in each of the countries studied, the peak of unhappiness was replaced by a gradually declining curve, as unhappiness decreased with age.

So, are middle-aged people happier now than they used to be? "Absolutely not. If there is any change, it is not in middle-aged people, who remain somewhat in the middle. Things have not changed much for them. All the changes are in the lower half of the age distribution," Bryson said.

The new trend is most pronounced in high-income English-speaking countries such as the UK and the US, and least pronounced in parts of Africa with poor internet access, he said. In Tanzania, for example, where only 32% of people had internet access in 2022, young people without internet access were significantly happier than those without access. Further research could help explain these findings, Bryson noted.

There could be a few reasons for the drop in happiness among young people, like them using social media more often or the fact that they're especially affected by the isolation caused by the COVID-19 pandemic, as well as having a hard time getting mental health services, he explained. | BGNES