Why does daylight saving time vary by country? - Big Questions - (Ep. 209) | Mental Floss

Hi, I'm Craig. Up until now I thought it was Daylight Savings Time, not Daylight Saving Time, and this is Mental Floss on YouTube

Today I'm going to answer Jerome's big question, why does Daylight Saving Time vary by country

Still sounds weird to me. Let's get started. Countries started using Daylight Savings Time, or DST, or DST, during World War I

To clarify, any time I say DST in this video, I'm referring to setting the clocks ahead in the summertime so the sun is out longer during the evening hours

then returning to what's known as standard time during the autumn. Germany was the first country to do this. They implemented it in order to save energy

The British adopted it shortly after, then most of the other countries in the war did too

In the US, observing DST was a federal law for both of the world wars, but after World War II, it became a decision of the states

Currently, the majority of countries in North America and Europe observe daylight saving time

Most countries in Asia and Africa don't. Only about 70 countries or one quarter of the world's population observe it

But a lot of countries have flip-flopped on DST over the years and probably will continue to

This is for a couple reasons. Some people believe that it saves energy. Some say that it's bad for health

And some think it's just an inconvenience. There's no clear consensus on whether daylight saving time actually saves energy

In 2008, the National Bureau of Economic Research, or NABUR, found that even though people used less light during DST, they used their air conditioning more

So there was actually an increase in energy Oh jeez The U Department of Energy on the other hand claims that 0 less energy is used annually thanks to DST Experts also don agree on whether it a health issue Come on experts can we all get along

Can we do some research? You're experts, find out if we can. Some studies show that our bodies never adjust to DST and it increases the risk of illness

Others say that an extra hour of sunlight encourages people to be healthy and exercise more

That said, I can't go through and tell you why each country does or doesn't observe DST, because my own daylight is limited and I have to save it

But I can give you some examples. In 2011, Russia declared that it would stay in DST year-round, but people hated it because

of the dark winters, so they switched to standard time. Some predominantly Muslim countries like Morocco don't use DST during Ramadan because people

fast during daylight, so they prefer the sun goes down earlier. Others just avoid DST altogether

In the US, two states regularly don't observe DST, Arizona and Hawaii

Arizona because they're a bunch of jerks. Hawaii because they're an island off in the middle of nowhere, it doesn't matter

No, Arizona, you're probably great. You haven't observed it since the 60s

believe that they're saving energy by not having an extra hour of sunlight, time that

people would likely spend running their air conditioning. And Hawaii's latitude makes it so that DST wouldn't affect them that much

They get basically the same amount of daylight no matter what season, and their weather is perfect all year round

Have you been to Hawaii? It's amazing. Thanks for watching Mental Floss on YouTube, made with the help of all of these nice daylight savers

If you have a big question of your own that you'd like answered, leave it below in the comments. See you next week