The general idea of ​​people is that we have brains They are larger than our ancestors. but Science I just found evidence that the human brain shrinks over time.

Even more intriguing, the culprit behind this fact is obesity, a condition that has increased in our species over the years.

Here are the results of a study that looked at the possible causes of brain shrinkage.

brain and obesity

The Investigation, led by anthropologist Jeff Morgan Staple, has found that over the centuries, brains of modern humans have diminished.

According to the expert, this is mainly due to the increase in human obesity.

brain and intelligence

The study proved that in the past four million years, the size of the human body has increased, with brain It grows at a disproportionate rate in relation to the rest of the body.

Brain augmentation is believed to be the main driver of the increase in cognitive ability observed in mammals. Thanks to this, humans were able to dominate the rest of the species.

But, unlike other humans, the brain block of modern man has decreased significantly in the last fifty thousand years.

Obesity is the culprit

It is not clear the reason for the size brain Humans have been in decline since at least the Late Pleistocene, but Stapel suspects nutrition may have something to do with it.

In their study, human remains were analyzed from the Holocene era until the end of the 1980s. Body and brain mass estimates were taken from each of them.

The result of the study indicates that the absolute size of brain Humans have declined on average by 5,415% over the past 50,000 years.

According to experts, the changes in human body size that occurred in those thousands of years would be the cause of the change in size brain Human.

Brains and fats

Stibel argues that reducing brain size is an adaptive response to changing physiology, particularly body mass, of modern humans.

By comparing changes in other hominins, which were generally stable, Stibel was able to discover that when obesity was controlled for, brain and body mass resembled that of prehistoric modern humans.

Previous evidence indicates this brain block Cognitive function is closely related throughout evolutionary history.

Is this worrying?

Study results prove that obesity has increased alarmingly worldwide in recent centuries.

Although it is not clear whether the physical changes in brain Or genetic predispositions will have a negative impact on human cognitive ability in the long run, Stapel believes we could experience widespread cognitive decline.

In fact, he points out that in the past thirty years there has been a significant decline in IQ, with the largest decline observed in industrialized nations.

Therefore, by taking care of your weight, you also care – in a way – about the future of humanity.