Nobody's Really Sure Whether Yogurt Is Good For You

If in a Back to the Future-esque scenario, someone from the year 1991 was flashed forward into 2015 and found themselves in front of the dairy aisle in a contemporary grocery store, or an office refrigerator, or a break room at a fancy gym, they would probably ask themselves, What the fuck is with all of this "Greek yogurt"?

Just a decade ago, the yogurt world was but a quiet sea of frilly, low-fat Yoplait flavors. But after the meteoric rise of Greek yogurt after Fage entered the US market in the early-to-mid aughts. Soon, Chobani had become the top-selling brand of yogurt in the US by 2011. Greek yogurt was just 4 percent of the US market in 2008, but had grabbed 52 percent of the industry by 2014.

Yogurt became near impossible to escape—and far more ingrained in our diets. Now, one out of three Americans regularly eats yogurt—and one of the major reasons is because of its supposed health benefits.

The health benefits of probiotics—a.k.a. the fun little strains of bacteria that gives yogurt its signature tang, and are found in other fermented foods such as kimchi and kombucha—are oft-discussed and little-proven, outside of their anecdotal success in treating digestive issues and feminine problems with errant "flora." Others have said that probiotics can aid everything from mental health to bad breath to weight loss.

The only problem: no one's totally sure whether yogurt actually does any of this.

And nothing demonstrates the lack of clarity about yogurt's benefits better than the fact that two studies came out today with completely conflicting implications about whether eating it actually does any good.

One study—as reported today in the UK's Guardian and originating from Lieden University in the Netherlands—found that one portion of yogurt or another probiotic food per day can actually help to fight depression, with a four-week regimen of probiotic food supplements resulting in "a significant reduction in negative and aggressive thoughts." This research appears to confirm the results of a 2013 study that found that eating yogurt twice a day can help to reduce stress, anxiety, and negative emotions. Sounds great, right?

But a Spanish study that just published its findings in the Journal of the Academy of Nutrition and Dietetics analyzed the yogurt intake and quality of life of more than 4,400 people and concluded that, definitively, "the regular consumption of yogurt was not linked to health-related quality of life," in the words of lead author Esther López-García. And in case you think that just means physical health, López-García notes that "although there was a slight improvement mentally, this was not statistically significant." In other words, the discrepancy can't be accounted for by yogurt consumption alone, or was too minor to be conclusive.

That's not to say that yogurt isn't rich in calcium, potassium, vitamins B and D, and low-fat protein—all of which are good for you. But if you're giving yourself Greek yogurt enemas on the reg, John Harvey Kellogg-style, thinking that your body is going to heal itself from the inside out because of your mass intake of fermented milk, you may want to remember that it isn't necessarily a miracle food.

But if yogurt makes you feel good—or enemas, for that matter—carry on.