Evan Amos via Wikimedia Commons // Public Domain
Evan Amos via Wikimedia Commons // Public Domain

The Modern Low-Fiber Diet May Be Damaging Our Microbiomes

Evan Amos via Wikimedia Commons // Public Domain
Evan Amos via Wikimedia Commons // Public Domain

We don’t talk about fiber all that much anymore. The high-fiber diet craze of the 1980s died quietly beneath the heel of the 1990s fat-free foods juggernaut, leaving lonely bran muffins to go stale in pastry cases. But fiber, passé though it may be, is still incredibly important for our health. A new study suggests that eating low-fiber processed food can weaken our microbiomes—and that we pass that weakness on to our descendants. The researchers published their findings today in the journal Nature.

This is a bigger deal than you might think. The communities of microorganisms that make up your microbiome affect more than just your gut. Researchers have linked microbiome health with depression, overeating, sexually transmitted disease, and more. It’s in our best interest to keep the tiny ecosystems in our bodies happy and healthy.

The first bacterial deposit in your microbiome bank was made while you were still in the womb. People take in bacteria through the birth canal, through breast milk, and through contact with their mothers’ skin. So the health of your family members’ microbiomes has a big impact on your own. And if their little ecosystems were deficient in some way, they could pass that deficiency on to you.

And unfortunately, we are looking a little deficient these days, says Stanford University microbiologist Erica D. Sonnenburg, the study’s lead author. “Numerous factors including widespread antibiotic use, more-frequent cesarean sections and less-frequent breastfeeding have been proposed for why we see this depletion in industrialized populations," Sonnenburg said in a press release. “We asked ourselves whether the huge difference in dietary fiber intake between traditional and modern populations could, alone, account for it.”

Why fiber? Fiber is hard for us to digest, so it passes through the intestines without being fully broken down. When those fiber leftovers reach the colon, they become a feast for the bacteria that live there. We need to keep feeding those bacteria to keep them alive. If they don’t get enough fiber, they’re not going to make it.

The odds are that our colon bacteria aren’t getting enough fiber. Our modern diets rely pretty heavily on processed foods, including white flour—that is, flour from which the fiber-rich husk has already been removed. Erica Sonnenburg’s husband Justin works with her at Stanford and was senior author of the study. He notes that members of industrialized societies are only getting about 15 grams of fiber a day. That’s one-tenth the amount consumed by hunter-gatherers, whose microbiomes are said to most closely resemble those of early humans.

So the Sonnenburgs and their colleagues set out to learn how a low-fiber diet affects the microbiome. They were curious about the changes both in individuals and across generations.

The researchers fed high-fiber and low-fiber foods to laboratory mice that had been specially bred for this purpose. The mice had been raised in sterile environments, which meant that they were starting with blank microbial slates. First, the mice were given a dose of bacteria taken from a human gut in order to reproduce the conditions of a human microbiome. Then the mice were divided into two groups. The first group ate a diet that contained plenty of plant-based fiber. The second group ate an identical diet, with one difference: Theirs contained almost no fiber.

The mouse poop was collected and tested at the beginning of the experiment and several weeks later. On day one, all of the mouse microbiomes looked pretty much the same. But a clear difference emerged pretty quickly.

“Within a couple of weeks, we saw a massive change," Justin Sonnenburg said in the press release. "The low-fiber-intake mice harbored fewer bacterial species in their gut." And not just a few less; some of the mice had lost more than 75 percent of the species they’d harbored at the beginning.

In the seventh week, the low-fiber mice were switched to high-fiber chow. After four weeks on this diet, the mice’s microbiomes had partially recovered—but only partially.

In a second experiment, the researchers bred several generations of mice, feeding them all a low-fiber diet. The mouse microbiomes became less and less diverse with every new generation. By the fourth round, the mice hosted only 25 percent of the bacterial species found in their great-grandparents. As before, changing the mice to a high-fiber diet helped some, but many of the species were irretrievably gone.

One thing did work: poop transplants. When the researchers implanted fecal bacteria from high-fiber-eating mice into their low-fiber counterparts, the microbiomes of the low-fiber mice made a full recovery.

So what does this mean for humans? “The extremely low-fiber intake in industrialized countries has occurred relatively recently," Justin Sonnenburg said in the press release. "Is it possible that over the next few generations we'll lose even more species in our gut? And what will the ramifications be for our health?"

We don't know yet. But in the meantime, it might not be a bad idea to give that bran muffin another try. Think of your grandchildren.

The World’s First Totoro-Themed Restaurant Is Coming to Thailand

Japan’s upcoming Studio Ghibli theme park will not open for another few years, but animation fans in Asia will soon have another destination where they can get their Hayao Miyazaki fix. Thailand will soon be home to a Totoro-themed restaurant, SoraNews24 reports.

May’s Garden House Restaurant in Bangkok is the first officially licensed restaurant inspired by Miyazaki’s classic film My Neighbor Totoro. The restaurant features Miyazaki-themed decor, like a giant Totoro figure that sits in the dining room, as well as menu items inspired by the characters, such as steamed buns shaped like Mini Totoros. The tables are adorned with figurines of Totoro, Mei, Sootballs, the Catbus, and other characters from the movie. While they aren't completed yet, the restaurant plans on adding a children’s playground, an orchid greenhouse, and various other elements before the grand opening.

Studio Ghibli co-founder Toshio Suzuki helped develop the concept for the restaurant, and he personally designed its sign. He also designed two exclusive new Studio Ghibli characters for the restaurant, Colko and Peeko (who you can see above).

While it has been open on a trial basis since mid-April, May’s Garden House is set to officially open at the end of May. Until then, Miyazaki uber-fans will have to content themselves with dining at the Straw Hat Cafe, the more general Studio Ghibli-themed restaurant at the Ghibli Museum in Tokyo.

[h/t SoraNews24]

Philippe Huguen, AFP/Getty Images
McDonald's May Be Getting Rid of Its Plastic Straws
Philippe Huguen, AFP/Getty Images
Philippe Huguen, AFP/Getty Images

First Seattle and then the Queen. Could the Golden Arches be next to join the anti-straw movement? As Fortune reports, McDonald's shareholders will vote at their annual meeting on May 24 on a proposal to phase out drinking straws at the company's 37,000-plus locations in the U.S.

If passed, the fast food behemoth would join the ranks of other governments and businesses around the world that have enacted bans against straws in an effort to reduce plastic waste. Straws are notoriously hard to recycle and typically take hundreds of years to decompose.

McDonald's is currently in the process of removing plastic straws from its roughly 1300 outlets in the UK. However, McDonald's board of directors opposes the move in the U.S., arguing that it would divert money from the company's other eco-friendly initiatives, The Orange County Register reports. This echoes comments from the plastic industry, which says efforts should instead be focused on improving recycling technologies.

"Bans are overly simplistic and may give consumers a false sense of accomplishment without addressing the problem of litter," Scott DeFife of the Plastics Industry Association told the Daily News in New York City, where the city council is mulling a similar citywide ban.

If the city votes in favor of a ban, they'd be following in the footsteps of Seattle, Miami Beach, and Malibu, California, to name a few. In February, Queen Elizabeth II was inspired to ban straws at royal palaces after working with David Attenborough on a conservation film. Prime Minister Theresa May followed suit, announcing in April that the UK would ban plastic straws, cotton swabs, and other single-use plastic items.

It's unclear how many straws are used in the U.S. By one widely reported estimate, Americans use 500 million disposable straws per day—or 1.6 straws per person—but it has been noted that these statistics are based on a survey conducted by an elementary school student. However, plastic straws are the fifth most common type of trash left on beaches, according to data reported by Fortune.

[h/t Fortune]


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