Why Do Average Heights Keep Increasing Across The World?

We keep hearing about how obesity rates are on the rise year after year, but we don’t hear too much about how the average height has also increased during that time. While the average height (based on human remains) bounced up and down for centuries, it remained at a pretty constant baseline. 

Ever since the late 19th century, though, the average height around the world has skyrocketed and only figures to increase with time. Why is this? Let’s take a look at why average heights keep increasing around the world.

1. Nutrition

We’re all told from a young age that if we want to grow up to be big and strong, we have to eat our vegetables and take vitamins. It turns out, it’s not just something your parents said to get you to eat broccoli. More people have access to food than ever before, and getting a wide range of nutrition allows people to reach their maximum height potential.

This wasn’t the case during the 1800s. Food was scarce around much of the country, and it wasn’t until around the 1950s that food was becoming more abundant. Technology that allowed foods to be frozen and shipped easier made the supply chains around the world better for those that had been lacking in food availability.

2. Living Conditions

You’ve probably heard a lot about overpopulation, especially at the beginning of the 21st century. Urban areas simply are running out of room, but that’s nothing compared to the overcrowding that the world was facing during the plague times. People were all in one central area, meaning that disease could spread quickly.

For most people, that isn’t the case anymore. Because of suburbs and liveable rural areas, people are as likely to fall extremely ill. Of course, there are still areas where people are essentially stacked up, but the conditions are far better than they were in the 19th century.

3. Natural Selection

We’ve all been told over the years that taller people are more attractive. The “apex of humanity” is typically seen as athletes, models, etc., all of which happen to be occupations where it pays to be tall. Because of this, taller people tend to have an easier time finding a mate, especially another tall one.

Long story short, tall people are having more babies with other tall people, continuing to increase the average height overall. That doesn’t mean that short people aren’t also having children, it just means that there are taller people to bring up the numbers with each generation.

4. Lack of Infectious Disease

We already mentioned the plague and how it affected the population and stunted the average height all those years ago, but it’s not the only disease that prevented humans from reaching their height potential. Due to modern medicine, infants are less likely to suffer from severe infections. 

This allows them to grow at a rate much faster than previous generations. This is especially true for respiratory infections. Pollution, especially via air, is another respiratory factor that comes into play. Pollution is still bad, but it’s nowhere near what it once was, and it has led to taller people.

Will It Continue?

The fact that humans have grown taller on average so rapidly since the start of the 20th century is a bit baffling to many scientists, actually. For many generations, shorter people were typically part of the lower class, and also had more children on average. That isn’t the case anymore, which has led to a large genealogical melting pot. 

Toward the end of the 20th century, the average height started to finally plateau a bit after decades of tremendous increase. Because of this, scientists believe that our average heights now are what we were capable of in the first place, but never got the chance to get there due to many circumstances. Health problems are common in overly tall people, so the plateau is expected to continue with a very slight increase over a long period of time in the future.