An Ancient Health Food Is Making A Ridiculous Comeback

America's newest health trend is really an ancient one: Bone broth.

Proponents of the savory solution claim it does everything from draw out toxins to sooth digestion and erase wrinkles. New Yorkers are shelling out up to $9 for to-go cups of the stuff.

In reality, the seemingly magical elixir is really just plain old broth with one added detail: the bones used to make it are slow-roasted, a process that's supposed to draw out nutrients.

But do a few extra hours of cooking and fresh ingredients make this stuff worth $9? We took a look at all of the purported benefits of bone broth so you can decide before you sip.

1. Detoxing

Bone broth fans say it helps rid the body of harmful toxins, the type that supposedly build up over a night of drinking or months of eating too much processed food.

Thankfully for us, our bodies come pre-equipped with their own natural detox system. While our kidneys filter our blood and remove any wastes from our diet, our liver processes medications and detoxifies any chemicals we ingest. Paired together, our bodies are natural cleansing powerhouses.

"Unless there's a blockage in one of these organs that do it day and night, there's absolutely no need to help the body get rid of toxins," family physician Ranit Mishori of the Georgetown University School of Medicine, who has spent years reviewing the medical literature on cleanses, told NPR.

2. Getting Back To Our Roots

Like advocates of the paleo diet - which excludes dairy, grains, and processed foods - bone broth fans say our cave-dwelling ancestors used the elixir to get all the nutrients they needed without any of the processed junk we eat today. Unfortunately for them, there's almost no archaeological evidence to support this idea. While there is limited evidence that early humans cooked food in containers - either inside holes in the ground or early versions of pots - there's no proof that they used them even to make soup, let alone as specific a concoction as bone broth.

Our paleolithic predecessors probably did cook bones, but the broth wasn't their main goal. "I was not aware that 'bone broths' became recently popular," Claire St-Germain, who manages the bone library at the Université de Montréal and studied bone broths for her anthropology masters, told us in an email. "Their main goal was the grease production."

Indeed, researchers have found evidence that cave-dwelling humans, who dined primarily on animal meat and needed fat to supplement their diets, heated bones to squeeze out their greasy, fatty innards.

3. Delivering Key Nutrients

One of the main ingredients in bone broth that makes it a "superfood," according to its fans, is proline, an amino acid that helps repair tissues and maintain blood pressure. Fortunately, as long as you eat enough protein (and most Americans are actually eating too much), you don't need any additional proline.

That's why it's classified as "non-essential" - because the body makes it on its own.

Another one of bone broth's "power nutrients" is glycine, an amino acid that is a building block of collagen, the connective tissue that makes up your skin and tendons, and creatine, which helps you build muscle. Again, your body makes glycine all by itself. Since you don't need any extra glycine, anything you eat that you don't use just ends up in your urine.

4. Soothing Tummy Troubles

The gelatin in bone broths is believed to coat the small intestine, preventing toxins from leaking out into the body and reestablishing a colony of healthy gut microbes. There is some limited evidence that this actually works, at least in animals.

A recent study in mice with acute colitis, for example, found that rodents given a gelatin powder for 7 days stopped losing weight. The lining of their intestine, which had been depleted by the disease, also appeared to regenerate enough to be seen under a microscope. When the researchers examined the mice given a placebo instead of the gelatin, they didn't see any alleviation of their symptoms.

Since no equivalent studies have yet been done in people, it's probably wise to hold off on jumping on the gelatin bandwagon for now, especially since powder is a much more concentrated form of the stuff than broth.

In the meantime, eating foods containing probiotics - like yogurt, miso soup, and some soft cheeses - might help soothe the stomach by reestablishing the balance of good and bad bacteria in your gut. Even then though, it's unlikely that a one-size-fits-all bacterial mix like those found in yogurt would be equally helpful to our wide variety of microbiomes.

5. Erasing Wrinkles

Collagen is a component of bone that also keeps our skin looking soft and supple. Many of the foods we eat, from dark leafy vegetables to nuts, fish, and beans contain ingredients that help the body produce collagen naturally.

Since our bodies produce it on their own, eating it directly probably won't have much of an impact. Like glycine, too much collagen is simply excreted by the body.