Half of all Americans - myself included - say that they're on a diet of some kind.
That must mean either our eating habits are totally out of whack, or we're too hard on ourselves about our weight. In all likelihood, both are probably true.
It's no secret that we eat more sugar and processed food but less fruit and veggies compared to older generations and other countries.
That's led some people to wonder if our ancestors understood a secret to eating healthy that we've since forgotten.
Diets based on "ancient" eating habits are getting popular these days, but how close did our ancestors actually stick to them?
The paleo diet
While this fad diet is all the rage these days, it was actually introduced in the early 1960s. Paleo is short for paleolithic, as in humans who used stone tools.
The basic idea is that ancient humans - meaning people who lived anywhere from 10,000 to 2 million years ago - had naturally healthier eating habits.
While there are dozens of books and diet plans, most paleo systems are very similar: you add as much meat to your diet as possible while cutting down on carbs. Then, enjoy some fruit and nuts for variety.
But if you actually believe ancient humans were closely following this diet, we have a bridge to sell you.
It's true that our ancestors were probably eating more fruit and nuts than the average American is these days.
But it's not like they could go to the grocery store for lean chicken breast every day. A real hunter-gatherer's diet could change from week to week, and there would be long stretches with very little meat.
Paleo diet followers also insist that humans aren't meant to eat grains, only meat and produce. But of course our bodies weren't designed to eat anything.
And choosing to go without an entire food group can cut crucial nutrients and vitamins out of your diet.
The real paleo diet
Before farming and animal rearing were common, it's true that humans would hunt and forage for food, or move to follow food sources with the season.
You can guess from their lifestyle that these early humans weren't very picky about meals. And there's evidence that they ate anything handy - including grain.
The biggest difference between your diet and your ancestors are actually the food staples that you take for granted every day.
A study by Colorado Statue University found that 70% of the average American's diet is made of four products our ancestors never encountered:
- Refined grain
- Refined sugar
- Dairy products
- Vegetable oil
So if you really wanted to copy their healthy habits, you could start by cutting white bread and flour, processed frozen meals, and soft drinks.
When it comes to foods like meat and cheese, natural, unprocessed varieties are also a smart choice. That means no cold cuts or hot dogs.
Remember this too: the fruit, vegetables, and nuts that we buy at the store are much healthier than the ones our ancestors used to snack on.
They've been grown selectively for thousands of years to be tasty and healthy, so consider yourself lucky.
Dairy and gluten intolerance
Fad diets that try to capitalize on our ancient ancestors also cut out dairy and gluten, because supposedly our bodies "aren't meant to eat those."
It's true that as little as 8,000 years ago dairy products made us sick. Humans could drink breast milk as babies, but gradually stopped breaking down dairy sugar called lactose as they got older.
Once humans started raising livestock and drinking their milk, our bodies slowly adapted to process lactose.
Today, at least 65% of people have some type of lactose intolerance - usually milk makes them gassy, or causes an allergic skin reaction.
But as long as your reaction isn't severe, there's no reason to take dairy products off your grocery list.
In fact, there are enough health benefits for foods like cheese, milk, yogurt, and kefir to earn them a place in any healthy diet.
Gluten intolerance is a little more tricky. Scientists are still divided on how many people are gluten intolerant, and what this really means for our health.
But they agree that unless you have serious reactions to products with gluten, there's no reason to switch to gluten-free pasta, bread, or cookies.
The 21st century diet
The biggest misconception about our ancient ancestors and their diet is that there was just one paleo diet.
Today, there are still small tribes of hunter-gatherers who live off the land and forage for food. But they don't exactly use the same cookbooks.
The !Kung tribe of Namibia and Angola eat next to no meat, and survive mostly on fruits, vegetables, seeds, and nuts.
Meanwhile, the native Inuit people of Alaska and Canada enjoy a large amount of meat and fish.
If you're looking to get in shape using a special diet, find one that suits your eating habits, not some imaginary caveman.
After all, ancient humans had plenty of unhealthy eating habits too. A survey of mummies from hunter-gatherer societies found almost all of them had clogged arteries.
Remember to keep everything in moderation. And getting a little more exercise wouldn't hurt either.