A Diet Lacking in Fiber Wreaks System-Wide Havoc, Scientists Find

It's more than just weight gain—it's chronic inflammation and weak immunity.

Photo: U.S. Air Force, Airman 1st Class Grace Lee.
Photo: U.S. Air Force, Airman 1st Class Grace Lee.

The first two episodes of the Netflix documentary series Rotten touch upon important issues in our relationship to food. The first focuses on the dangers of colony collapse in bee populations as well as international companies filling bottles with ingredients that definitely are not honey. The second deals with food allergies, particularly focused on the largest: peanuts.

While these are distinct issues, two themes weave these stories together. First, the impact of our environment on health. Humans have gone to great lengths to separate from nature. Yet we interact with whatever environment we live within. Effects of sedentary existences lived apart from the planet’s rhythms include the slow destruction of our bodies and pretty much every species we come into contact with.

The booming almond industry needs pollinators, which stressed beekeepers (and bees) travel hundreds or thousands of miles to accomplish in California’s central valley each season—adding to the stress. Colony collapse is rampant given the diseases these nomadic bees are now sharing. This is but one example of interdependence that we often overlook. No pollination, no honey, no almonds, no—a lot. 

The rapid onset of food allergies over the course of only one generation provides another example of our exile from nature’s rhythms. We would never eat foods apart from the environment they were grown or captured within until recently. Industrial monocultures are likely, at least in part, to blame for this stunning increase in any or all of the eight allergens, which leads us to the second theme in these episodes: our microbiome. 

These 8 foods make up 90% of all food allergies in the U.S. Image: Fix.com

The bacteria that live inside of our guts is arguably the most important feature of our entire body. While the brain receives the bulk of praise, scientists have more recently raised an inquisitive eyebrow regarding all the data emerging on the microbiome. The relationship between our nervous system and gut (which has its own nervous system) is exceptionally influential on health. 

Our microbiome also directly interacts with our environment. While Purell has proven beneficial for soldiers in foreign territories, constantly sanitizing your hands weakens your immune system when in home territory. Synopsis: let your kids play in dirt. You play in dirt too. Those bacteria are strengthening.

Yet we have many weird relationships with our environment and the foods we eat, often in the invented cause of “purity.” One example is juicing, heralded as the perfect (and profitable) “cleansing” mechanism. Drink juice for five or ten days and your body “resets.” But juice is no different than soda, as you’ve removed the most beneficial part of the fruit: fiber. 

We’ve long known fiber is essential to our diet, in order to “get things moving.” Otherwise known as roughage, dietary fiber is comprised of soluble and insoluble fiber. Both play critical roles in defecation. While too much fiber can cause intestinal gas and bloating, too little, a hallmark of a highly processed diet heavy on sugar, means we’ll turn to laxatives instead of eating the fruits, plants, and grains that offer an abundance of it. 

Fiber also reduces the risk of heart disease, arthritis, and diabetes, and has been shown to lower mortality rates. But its role in digestion is particularly important. The food we consume is broken down by enzymes, its nutrients absorbed by our intestines. The molecules we cannot absorb, fiber, either pass through or, as it turns out, become food for gut microbes. 

A recent study published in Cell Host and Microbe investigates mice on a low-fiber, high-fat diet. The gut bacterial population crashed, triggering immune reactions. A similar experiment, published in the same journal, discovers that the effects of a low-fiber diet are wide-ranging: 

Along with changes to the microbiome, both teams also observed rapid changes to the mice themselves. Their intestines got smaller, and its mucus layer thinner. As a result, bacteria wound up much closer to the intestinal wall, and that encroachment triggered an immune reaction.

Continuation of this diet causes chronic inflammation; the mice also got fatter and developed high blood sugar. In both cases, the inclusion of a fiber called inulin dramatically improved their health and gut bacteria population. The researchers, which include Georgia State University’s Andrew T. Gewirtz, realized that fiber serves as an essential food for an entire population of bacteria. 

"One way that fiber benefits health is by giving us, indirectly, another source of food, Dr. Gewirtz said. Once bacteria are done harvesting the energy in dietary fiber, they cast off the fragments as waste. That waste — in the form of short-chain fatty acids — is absorbed by intestinal cells, which use it as fuel," writes Carl Zimmer for The New York Times.

The “peaceful coexistence” of bacteria in the microbial system is disturbed on a low-fiber diet. Famine breaks out. Bacteria dependent upon fiber starve, followed by the bacteria that depend upon them for sustenance. A colony collapse. What follows isn’t a disappearance, but an aggravation. 

"Inflammation can help fight infections, but if it becomes chronic, it can harm our bodies. Among other things, chronic inflammation may interfere with how the body uses the calories in food, storing more of it as fat rather than burning it for energy," writes Zimmer.

Obesity isn’t the only thing fiber fights. It is also believed to help combat or prevent immune disorders. A fiber supplement probably won’t cut it, however, since what our microbiome truly craves is a variety of fiber sources, which, fortunately, can be found in the produce aisle. 

We begin life with a disadvantage regarding fiber. In his book, Catching Fire, British primatologist Richard Wrangham writes that our relatively small colon means we cannot utilize plant fiber nearly as effectively as great apes. Cooked food provides an important means for intaking more fiber (and other nutrients) than raw plants, but thing is, we have to eat those plants. 

A diet filled with processed foods and fiber supplements is not going to cut it. Our microbiome craves what it has evolved to need in order to survive. Without those requirements those bacteria perish, initiating system-wide havoc in our bodies. Sans fiber we’re not honoring the environment that gave birth to us, and that environment is certainly speaking back. 


Derek Beres is the author of Whole Motion: Training Your Brain and Body For Optimal Health. Based in Los Angeles, he is working on a new book about spiritual consumerism. Stay in touch on Facebook and Twitter.

A landslide is imminent and so is its tsunami

An open letter predicts that a massive wall of rock is about to plunge into Barry Arm Fjord in Alaska.

Image source: Christian Zimmerman/USGS/Big Think
Surprising Science
  • A remote area visited by tourists and cruises, and home to fishing villages, is about to be visited by a devastating tsunami.
  • A wall of rock exposed by a receding glacier is about crash into the waters below.
  • Glaciers hold such areas together — and when they're gone, bad stuff can be left behind.

The Barry Glacier gives its name to Alaska's Barry Arm Fjord, and a new open letter forecasts trouble ahead.

Thanks to global warming, the glacier has been retreating, so far removing two-thirds of its support for a steep mile-long slope, or scarp, containing perhaps 500 million cubic meters of material. (Think the Hoover Dam times several hundred.) The slope has been moving slowly since 1957, but scientists say it's become an avalanche waiting to happen, maybe within the next year, and likely within 20. When it does come crashing down into the fjord, it could set in motion a frightening tsunami overwhelming the fjord's normally peaceful waters .

"It could happen anytime, but the risk just goes way up as this glacier recedes," says hydrologist Anna Liljedahl of Woods Hole, one of the signatories to the letter.

The Barry Arm Fjord

Camping on the fjord's Black Sand Beach

Image source: Matt Zimmerman

The Barry Arm Fjord is a stretch of water between the Harriman Fjord and the Port Wills Fjord, located at the northwest corner of the well-known Prince William Sound. It's a beautiful area, home to a few hundred people supporting the local fishing industry, and it's also a popular destination for tourists — its Black Sand Beach is one of Alaska's most scenic — and cruise ships.

Not Alaska’s first watery rodeo, but likely the biggest

Image source: whrc.org

There have been at least two similar events in the state's recent history, though not on such a massive scale. On July 9, 1958, an earthquake nearby caused 40 million cubic yards of rock to suddenly slide 2,000 feet down into Lituya Bay, producing a tsunami whose peak waves reportedly reached 1,720 feet in height. By the time the wall of water reached the mouth of the bay, it was still 75 feet high. At Taan Fjord in 2015, a landslide caused a tsunami that crested at 600 feet. Both of these events thankfully occurred in sparsely populated areas, so few fatalities occurred.

The Barry Arm event will be larger than either of these by far.

"This is an enormous slope — the mass that could fail weighs over a billion tonnes," said geologist Dave Petley, speaking to Earther. "The internal structure of that rock mass, which will determine whether it collapses, is very complex. At the moment we don't know enough about it to be able to forecast its future behavior."

Outside of Alaska, on the west coast of Greenland, a landslide-produced tsunami towered 300 feet high, obliterating a fishing village in its path.

What the letter predicts for Barry Arm Fjord

Moving slowly at first...

Image source: whrc.org

"The effects would be especially severe near where the landslide enters the water at the head of Barry Arm. Additionally, areas of shallow water, or low-lying land near the shore, would be in danger even further from the source. A minor failure may not produce significant impacts beyond the inner parts of the fiord, while a complete failure could be destructive throughout Barry Arm, Harriman Fiord, and parts of Port Wells. Our initial results show complex impacts further from the landslide than Barry Arm, with over 30 foot waves in some distant bays, including Whittier."

The discovery of the impeding landslide began with an observation by the sister of geologist Hig Higman of Ground Truth, an organization in Seldovia, Alaska. Artist Valisa Higman was vacationing in the area and sent her brother some photos of worrying fractures she noticed in the slope, taken while she was on a boat cruising the fjord.

Higman confirmed his sister's hunch via available satellite imagery and, digging deeper, found that between 2009 and 2015 the slope had moved 600 feet downhill, leaving a prominent scar.

Ohio State's Chunli Dai unearthed a connection between the movement and the receding of the Barry Glacier. Comparison of the Barry Arm slope with other similar areas, combined with computer modeling of the possible resulting tsunamis, led to the publication of the group's letter.

While the full group of signatories from 14 organizations and institutions has only been working on the situation for a month, the implications were immediately clear. The signers include experts from Ohio State University, the University of Southern California, and the Anchorage and Fairbanks campuses of the University of Alaska.

Once informed of the open letter's contents, the Alaska's Department of Natural Resources immediately released a warning that "an increasingly likely landslide could generate a wave with devastating effects on fishermen and recreationalists."

How do you prepare for something like this?

Image source: whrc.org

The obvious question is what can be done to prepare for the landslide and tsunami? For one thing, there's more to understand about the upcoming event, and the researchers lay out their plan in the letter:

"To inform and refine hazard mitigation efforts, we would like to pursue several lines of investigation: Detect changes in the slope that might forewarn of a landslide, better understand what could trigger a landslide, and refine tsunami model projections. By mapping the landslide and nearby terrain, both above and below sea level, we can more accurately determine the basic physical dimensions of the landslide. This can be paired with GPS and seismic measurements made over time to see how the slope responds to changes in the glacier and to events like rainstorms and earthquakes. Field and satellite data can support near-real time hazard monitoring, while computer models of landslide and tsunami scenarios can help identify specific places that are most at risk."

In the letter, the authors reached out to those living in and visiting the area, asking, "What specific questions are most important to you?" and "What could be done to reduce the danger to people who want to visit or work in Barry Arm?" They also invited locals to let them know about any changes, including even small rock-falls and landslides.

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Credit: Pixabay
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