美国国家公共电台 NPR Is The Secret To A Healthier Microbiome Hidden In The Hadza Diet?

ARI SHAPIRO, HOST:

The phrase endangered species often refers to charismatic animals like mountain gorillas 1 or polar bears. Well, today scientists are reporting that a whole different type of extinction 2 is happening inside our bodies. NPR's Michaeleen Doucleff explains.

MICHAELEEN DOUCLEFF, BYLINE 3: So if you want to see where this extinction is happening, just look down at your belly 4. Inside there is a whole ecosystem 5. Yes, I'm talking about your microbiome, which contains more than a thousand species of bacteria. Justin Sonnenburg at Stanford says they are powerful critters.

JUSTIN SONNENBURG: These microbes influence biology all over our bodies. So they're affecting our immune system, our metabolism 6.

DOUCLEFF: Even our brains.

SONNENBURG: So moods and behavior can be affected 7 by our gut 8 microbes. So it's really an important community for our health.

DOUCLEFF: A community, Sonnenburg says, that's in danger. Today in the journal Science, he and his colleagues report that some bacteria inside our guts 9 are disappearing.

SONNENBURG: Over time, we are losing valuable members of our gut community.

DOUCLEFF: Sonnenburg and his colleagues analyzed 10 the microbiomes of 18 different cultures around the world, including traditional cultures like hunter-gatherers in Tanzania who don't eat any processed food or refined sugars. The findings were crystal clear. The further away people's diets are from a Western diet, the more variety of microbes they have in their guts, including bacteria that are missing from Americans.

SONNENBURG: We've come to realize how important this gut community is for our health, and yet we're eating a diet that totally neglects them. So we're essentially 11 starving our microbial selves.

DOUCLEFF: In other words, a Western lifestyle has wiped a few species from our digestive tracts 12. Jens Walter, a microbiologist at the University of Alberta, says now the big question is, how is this affecting our health? He talked to us on Skype and says one hypothesis is that losing those bacteria has contributed to the rise in autoimmune diseases, including diabetes 13.

JENS WALTER: All these diseases, you know, they have skyrocketed within the last 50 or 60 years.

DOUCLEFF: And they've already been linked to the microbiome in animal models.

WALTER: Although we lack a definite proof, at least the picture or the puzzle is getting more and more complete. And everything points to that hypothesis.

DOUCLEFF: And keeping people healthy likely means keeping the critters inside of us healthy and happy. Michaeleen Doucleff, NPR News.