Take fermented foods on hikes
Takeaways: fermented foods improve your immune system, no amount of exercise can make up for a crappy diet,
3 Tales of Food, Some Fermented
I promised three tales of food, two of which would be about fermented foods. Actually, two of them are also about hiking and food and I think taken together you will learn some new things, I sure did.
Tale 1: Out of Shape + 8 days + Fermented Foods = Happy Survival
Some of you know that in 2019 Kirsten and I backpacked for a week through Torres Del Paine National Park in Patagonia with two of our sons and their partners. That makes it sound like our idea, and we brought them along, which was not the case. Our kids are all adults, two of them are married, we have three grandkids now, so the tables have turned. For the rest of our ride on this Earth, I think it will be them having adventure ideas and trying to coax us off the farm and away from the ease of daily life.
This adventure involved the "O" route, which everything I read described as physically demanding, and there was the part about no camping unless in designated "refugios," government campsites that take months to get a reservation. So we had to make our decision quickly—something I am never fond of nor good at doing. As usual, Kirsten said yes, and I said no. Then she began eroding my poorly constructed arguments, and I shifted to a stark countdown to 8 days hiking with 50+ pounds in a pack I didn't yet own that just walking up the hill behind our farmhouse made me short of breath.
As any out-of-shape cookbook author with a shred of self-respect, we started training in secret. Helpful REI people carefully fitted us with large backpacks, and I have to say, an empty pack gives one a feeling of already accomplishing something. I think owning a Jeep must feel like that. By just owning it, you are already a little bit healthier. We used dry beans and anything else in the pantry that looked like it would fit and not make a mess for increasing weight training. I sometimes thought that if we both had fallen off the trail and down a ravine, strapped like turtles to shells too large for us, they would have wondered why these people's backpacks were full of dry beans in heavy half-gallon mason jars. The other thing we did was make our own <fermented> trail foods. Okay, that's a lie. Kirsten came up with all the recipes (like most of our books), and I was her fearless taster, which is an excellent job, by the way. See the previous offer to hang out with Kirsten and if you do you can ask her all about it, as well as come up with tasty creations and ways to eat them. She is really good at that.
We didn't know it was illegal to enter Chile with homemade food, and given how little fermented foods have taken hold there, my guess is there would have been extra jail time for the fermented stuff. But for some stroke of luck, we were waved through customs. Once on the trail, everyone is going one way and camping at the same designated areas, so you quickly get to know each other. We were the oldest on the trail, I think, and the only ones with our own food—funky food that we were sharing and teaching how to make by the end. As Kirsten promised, I survived, and I enjoyed myself, which again happens just about every time despite what I know beforehand. That part can be frustrating.
End of the first tale, two out-of-shape cookbook authors on the trail for eight days, with nutritious fermented foods, that do better than their kids or themselves thought they would. Now to a different trail, a different hiker in a very different condition, and a far less harmless diet than he thought.
Head to this post to read about natto with a recipe for Natto Bites — our favorite high energy super hiking snack. We do have to say they are delicious whether you hike or not.
Tale 2: Super Shape + 112 days + Crappy Foods = Surprising Aging
This week I read a story in Outside magazine because of the title: Could Thru-Hiking Be Bad for Your Health? A New Study Makes a Troubling Find. There has been messaging within the family of a partial Pacific Crest Trail hike, and I was attracted to this title for obvious reasons. It is the story of a man quite the opposite of me, young and in remarkable shape, who is in such good condition he does push-ups along his way to completing the entire PCT a month faster than most. In his previous hike of the Appalachian Trail, he earned the trail name Tarzan. I acquired no trail name in Patagonia, but people smiled at me as I stood beside the trail for them to pass, and they would say kind things, like Good for you! Meaning I think, good for you that at your age you are doing this! Or maybe they meant I reminded them of Tarzan, but it was a language thing, and I misunderstood. Anyway, back to Mr. Heinbockel's story because it is about to take a surprising turn. Unlike nearly everyone that sets out on a long through-hike, Heinbockel works at the University of Colorado and, just as a personal interest, gets a full medical workup before leaving. Upon returning to the lab after his speedy 112 days, he submits to the same medical tests. The results were surprising and were written up recently in Physiological Reports, March edition.
Regarding body weight, body mass index, and body fat percentage, not much had changed; however, they found that his calorie-rich but nutrient and fiber-poor diet had caused aortic stiffness despite the continuous exercise. Specifically, they measured his endothelial function in his brachial artery through something called a flow-mediated dilation, FMDBA, if you are playing along at home. This measurement decreased markedly, which the study said may indicate heightened disease risk following the through-hike.
In conclusion, they stated, "our findings suggest that large volumes of exercise do not compensate for a poor diet and/or may provide diminishing returns and prove detrimental to physiological function." So much for exercising so much that you can eat whatever you want. I, for one, am glad to have learned this before beginning a 12-hour-per-day exercise routine just so that I can eat as much junk food as I want. Maybe I saved you from a similar fate. Whew, you are welcome.
Tale 3: Fiber vs Ferments: Smackdown for Our Microbiota’s Love
We leave the trails for this third story, but not the idea that what we eat makes a difference. A study was just published that directly addresses a three-way relationship going on inside of you and me. What we choose to eat affects our gut microbiome, which affects our immune system. As the mysterious monkey in the middle, our unique gut microbes are better understood every day. Now we are in an age of figuring out what microbial mix in the middle best supports and strengthens our immune system, then what diet optimizes the conditions for those microbes. To me, it sounds like precision medicine just focuses upon the microbiome.
This study picked two top contenders for diets that positively affect our microbiome: fiber-rich diets and fermented foods. On the fiber side, you might remember from previous nerd posts that dietary fiber provides microbiota accessible carbohydrates or MACs for short. The product of those microbes consuming MACs includes short-chain fatty acids (SCFAs), which we have discussed regarding helping maintain our gut barrier and keeping inflammation down. Unfortunately, Americans, and now most of the world's populations, are not getting enough dietary fiber, which could weaken immune systems globally. The other contender, a hometown favorite for this community, is fermented foods. Studies cited linked the consumption of fermented foods with decreased diabetes, cancer, and cardiovascular disease risks, earning it the contender slot. It's high ferment versus high fiber for 17 weeks, monitoring both microbiome and immune status as the judges.
The study was made of 36 participants evenly divided between the two diets. The majority were in their 40's to '60s, female, white, and well educated. The first three weeks defined their baseline, followed by a four-week ramp-up that led to a six-week maintenance phase. After that, they had four weeks where they were free to choose what they ate. Stool samples told the story of changing microbiota composition while blood samples allowed for accessing their immune system.
From the baseline start through the maintenance phase, changes were documented. For the high fiber team, not surprisingly, they increased their soluble and insoluble fiber and carbohydrates. Vegetable protein also increased, and there were modest increases in calories and select vitamins and minerals. Their consumption of animal proteins and sodium decreased. Team Ferment showed a rise in animal proteins due to the fermented dairy products. Now comes the finding that I have been asked about for more than a decade. Despite the high consumption of fermented vegetables and fermented brine drinks, the participants' sodium intake did not change. Also, they noticed decreased inflammatory markers for Team Ferment and increased microbiota diversity from the beginning of baseline through the maintenance phase.
Perhaps most surprising, the Team Fiber participants' microbiota diversity did not change substantially with the high fiber diet, though the researchers hypothesized it would. However, they did note that based upon the abundance of microbial proteins per gram of stool sample, their microbiota density did increase. Therefore, the researchers speculate that the local microbiota did not have enough time to respond to the increased fiber food source adequately.
Team Fermented Foods saw an overall increase in the diversity of participants' microbiota. Furthermore, this diversity was sustained during the final phase, where participants were allowed to choose what they ate, which suggests reinforced changes to their microbiomes. Scientists also observed decreased level of activation of cells involved in inflammation. A significant correlation was observed between SCFAs and butyrate production in the stool samples and immune cell frequency.
So, what to make of this? First off, where did the new microbes come from with the fermented foods group? The scientists aren't sure, offering that it probably wasn't directly from the foods, leaving that they were recruited from the participant's body or already there, but in such small numbers to not be detected. However, what I find interesting when digging into their findings was that the increase in diversity was a steady building up through the last choice phase. So, you really can increase your gut microbiota diversity through a diet of fermented foods. You know from an earlier letter about our gut and immune system relationship so this evidence further strengthens that understanding.
Where does this lead? First, I can see where dietary interventions will begin with stool and blood samples to establish a baseline of the diversity of our microbiomes. Secondly, with a map of our microbiota married to health goal interventions, custom diets will be created to target the microbes known to positively affect the changes we want to see in our immune response.
Studies:
Thomas C. Heinbockel Daniel H. Craighead
Gut Microbiota-Targeted Diets Modulate Human Immune Status
Hannah C. Wastyk, Gabriela K Fragiadakis, Dalia Perelman, Dylan Dahan, Bryan D Merrill, Feiqiao B. Yu, Madeline Topf, Carlos G. Gonzalez, Jennifer L. Robinson, Joshua E. Elias, Erica D. Sonnenburg, Christopher D. Gardner, Justin L. Sonnenburg
I am a backpacker and have been trying to figure out ways to incorporate more living and fermented foods into my trail meals. Would you be willing to share what foods you brought on your hike? I would be thrilled to have your input! Thanks!