We sure have discovered a lot of things that are bad for us over the last 50 years.
When our grandparents were growing up, the world was a Wild West of unhealthy choices.
You could smoke, drink, and eat with abandon.
These days, we have a lot more laws designed to nudge Americans to live their lives in a healthier way.
Here are 10 things our grandparents probably did back in their day — some of which you're likely still doing — before science figured out they were bad for us:
In 1950, almost half of Americans smoked.
Today, one in five American adults still use tobacco products. But now they probably know about all the risks.
Ate processed meats
While the health effects of eating unprocessed red meat like fresh beef and pork in moderation are contested, scientists have found that processed red meat is not good for us.
This is likely because processed meat contains a lot of salt, which can raise your blood pressure and cholesterol, eventually leading to heart problems.
Heart disease and cancer are the two leading causes of death in the US, and we still haven't kicked the carnivorous habit. In fact, we've gotten worse.
In 1950, an average American ate 138* pounds of meat per year. Today, that number's risen to over 195 pounds.
*Correction: A previous version of this post said an average American ate 57 pounds of meat in 1950; it’s actually 57 pounds less than a modern American.
That's thanks to driving under the influence laws across the country. New York passed the first one in 1910, and the rest of the states soon followed, but the laws didn't get specific enough to really make a difference until the '70s.
Raising the drinking age to 21 in the 1980s and '90s helped, too.
Since 1982, drunk driving fatalities have declined 53%, though today around 10,000 people still die every year in crashes caused by a drunk driver.
Ate lots of sugar
Research has found that diets high in added sugars are associated with an increased risk of obesity, diabetes, heart disease, cancer, and cavities.
That number has been creeping up over the last century, as sugars are added to more and more processed foods and Americans drink a disturbing amount of soda. That's all in spite of the fact that we should really know better by now.
Celebrated processed foods
The middle of the 20th Century was all about convenience. How could we make everything in our lives cheaper and easier with science?
This was especially apparent in the food industry. Companies were coming up with ways to extend shelf lives and freeze anything they could so consumers could have access to food anytime they wanted.
This startling reliance on ultra processed foods is making us "overfed and undernourished," the researchers wrote, because they're often high in added sugars and low in nutrients. It's why people call them "empty calories."
Ultra-processed foods account for 90% of the added sugars in Americans' diets, and we know how bad those are.
Today, Americans consume over 152 pounds of sweeteners per year. That's 43 more pounds than in the 1950s.
The main culprit is soda. In 2000, soft drinks made up over a fifth of the added sugars in the entire food supply, according to the US Department of Agriculture.
Drinking less soda may be the quickest way to cut sugar from your diet, and avoid its negative health effects.
Ate trans fats
Crisco, and other manufactured fats like it, was an unbelievable invention in 1911. Trans fats were cheap, they made food delicious, and they could even extend shelf life.
But they can also raise your cholesterol, increasing your risk for heart disease.
Didn't wear seat belts
In 2014, 87% of people used seat belts, but half of the people who died in car crashes weren't wearing them.
Seat belts save 13,000 lives a year, according to the National Highway Traffic Safety Administration.
New cars didn't even get seat belts until the 1960s, and state laws didn't require people use them until the '80s.
The first car to start obnoxiously dinging when you don't buckle up came out in 1998, to give the final push for people to wear their seat belt.
Biked around without a helmet
A majority of biking deaths involve the head and face. Studies have found that helmets can reduce head injuries by 65%.
But fewer than half of American kids wear bike helmets. If only they were considered cooler.
Tanned without sunscreen
Our grandparents were told to go play outside in the sun as kids.
And while that's still great advice, the problem was that they probably didn't wear sunscreen.
Yet only 14% of men and 30% of women said in 2013 they wear sunscreen when they're outside for more than an hour.
We've figured out that these things are bad for our health, but it's taking a lot longer to actually stop doing them.
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