An estimated 40 trillion microbes make up our gut microbiome. Researchers are now studying how these microbes protect our immune system, fighting off viruses like Covid-19.
“Imagine microbes that block a virus from entering a cell or communicate with the cell and make it a less desirable place for the virus to set up residence,” says Mark Kaplan, chair of the department of microbiology and immunology at the Indiana University School of Medicine. “Manipulating those lines of communication might give us an arsenal to help your body fight the virus more effectively.”
These microbes, according to an article in National Geographic, may fight viruses in one of three ways: “building a wall that blocks invaders, deploying advanced weaponry and providing support to the immune system.” Kaplan calls intestinal bacteria “the gatekeepers between what we eat and our body.”
The article details the new, innovative measures medical professionals are taking to repair a patient’s damaged gut microbiome — transplanting fecal matter, administering a bacteria-targeting virus and pills that release antiviral interferons. But the most compelling way may be consuming a diet rich in fermented foods — the article notes a consensus among medical and science professionals that fermented foods can promote a healthy microbiome.
Read more (National Geographic)
This is the first in a series of articles that TFA will be releasing over the next few months, analyzing trends from our Member Survey.
Though fermentation brands overwhelmingly reported substantial sales gains during the Covid-19 pandemic, they’re not breaking out the champagne. Now, nearing fall 2021, many are starting to see sales flatten. This trend is consistent with sales for the food industry at large, which started to plateau in March 2021.
Most fermenters reported struggles meeting demand — packaging shortages (38%), costly and time-consuming Covid-19 sanitation protocols (30%), distribution delays (29%) and ingredient and labor shortages (both 28%). Then there’s the challenge of keeping a fermented product in stock with constantly changing sales demands.
Jared Schwartz, a TFA Advisory Board member, is founder of fermented sauce producer Poor Devil Pepper Co. and director of operations and quality for Farm Ferments (a facility in Hudson, N.Y., that is home to Hawthorne Valley Farm). He says forecasting has been especially difficult for a refrigerated fermented food with a processing cycle more delicate than that of its shelf-stable counterpart.
“While these spikes in sales are incredible, they also depleted our on-hand WIP [Work-In-Progress],” Schwartz says. He would project barrels of fermenting vegetables to provide adequate inventory for a certain length of time, but peak pandemic demand depleted stock. Finding new ingredients is difficult because everything is sourced locally. “With fermentation, there is of course a much longer lead time on a finished product as the process can’t be rushed. So these challenges left us extending our production season and looking to source from the spot market, which is generally out of our norm. We generally source 95% of our ingredients from New York State and base our projections around the trajectory aforementioned.”
Sales Flatten After Record Year
While predicting sales has been difficult — especially as many states are again increasing Covid-19 restrictions because of the Delta variant — some brand leaders were prepared for a decrease in sales in 2021.
Kheedim Oh, founder of Mama O’s Kimchi (and also on TFA’s Advisory Board), said sales doubled in 2020. But, this summer, they fell dramatically from that peak. “July was terrible,” Oh says, but they “anticipate a boost in the fall since summer months are typically slower.”
Revenue almost tripled in 2020 for hard kombucha brand Dr. Hops, but sales have since started to flatten. The company had secured new distribution before the pandemic, then redesigned their product line this year. “We would have likely done much more… if we had been able to do all the field sales and marketing we had planned,” says Joshua Rood, co-founder and CEO of Dr. Hops Real Hard Kombucha,
Hawthorne Valley is seeing a similar downturn. Sales from March to April spiked about 50%, with overall year-over-year growth at 46%. But “things have definitely plateaued for now,” Schwartz says.
Supply Chain Nightmares
Small packaging supplies — like the tiny plastic caps for glass kombucha bottles — caused huge production issues. Hannah Crum, president of Kombucha Brewers International, says this was the biggest challenge for brewers. “It’s had a massive impact,” she says.
Twenty-four percent of survey respondents said they anticipate production constraints will continue to be a challenge throughout 2021.
And though sales remain strong for Bubbies pickles according to John Gray, owner of Bubbies (and TFA Advisory Board member), “glass shortages have affected the entire industry. Sales are strong, but shortages persist,” as he describes the pandemic’s double-edged sword facing many fermented brands.
Production and distribution issues hit frozen pizza brand Alex’s Awesome Sourdough, too — packaging costs went up 10%, and freight expense nearly doubled. But these didn’t slow the company’s growth. They expanded massively in 2020, from 100 to 1,500 stores. An overall uptick in frozen food sales helped them as well, especially as competing pizza brands went out of stock.
“Sales are strong as pizza is a seasonal category and the end of summer and early fall are the beginning of peak season,” says Alex Corsini, founder of Alex’s Awesome Sourdough (and another TFA Advisory Board member). “We anticipate sales being even stronger if Covid protocols remain strict and restaurants continue operating at a limited capacity. Restaurants definitely take a piece of our pie (pun intended).”
The New York Times breaks down “The Dos and Don’ts of Fermented Foods” in a new article. Food science writer, Anahad O’Connor, was interviewed to answer some of the most frequently asked questions about fermented foods. For example: What are the differences in sugar content of yogurt brands? How can fermented foods be incorporated into daily life?
O’Connor says there are “thousands of different types of fermented foods consumed around the world” that “are chock-full of live microorganisms, known as probiotics, and they are widely available at grocery stores, supermarkets and farmers’ markets.”
He shared his advice for shopping for fermented foods, pointing out: “Not all foods that are made through fermentation contain live microorganisms when they reach store shelves or your kitchen table.” Sourdough, for example, loses all fermented bacteria once baked. Most wine is filtered and processed to make any live microbes disappear. Fermented foods packaged with statements like “containers probiotics,” “contains live cultures” or “naturally fermented” are good products to look for — and most are in the refrigerated aisles.
Read more (The New York Times)
In America, where 40% of the population identifies as nonwhite, why do grocery stores still have an ethnic aisle? The outdated aisle initially began after World War II as a way for soldiers to buy the food they ate while in Italy, Germany or Japan. But the European foods, like pasta sauces and sauerkraut, eventually became integrated with the rest of the store, while foods from BIPOC countries stayed put.
Heads of ethnic food brands and grocery chains have been pushing for a change, but it’s been a hard sell. Doing away with the aisle is a layered problem — and still not the most popular approach with food professionals.
“Several food purveyors of colors see the aisle as a necessary evil — a way to introduce their products to shoppers who may be unfamiliar with, say, Indian food — though a barrier to bigger success,” reads an article in The New York Times.
Some ethnic brands come to store buyers with little capital to get their products on the shelf, so the only spot for them is on the ethnic aisle. They will never break out unless they’re acquired by a larger company. Larger corporations, like Pepsi or Nestlé, can afford to pay stores to put their products on shelves with prime product placement. And large ethnic brands (like Goya beans and Maruchan ramen) are placed on both ethnic aisles and their respective traditional product section because they’re considered broadly recognized.
But many products with international flavors made by nonwhite brands are not placed on the ethnic shelf. The Times shares the story of Toyin Kolawole, who runs the African ingredients brand Iya Foods. Kolawole tried to get her cassava flour into the flour aisle with a Midwestern retailer with no success. But when cassava flour began trending as a substitute for traditional flour, bigger companies launched their own cassava brands — which were put in the flour aisle.
On the flip side, other food professionals note that consumers turn to the ethic aisle in search of international flavors. Customers like the convenience. There is a fear that unique ingredients (like tamarind or pomegranate molasses) without a clear spot in a grocery store would get lost in a conventional aisle. And, even worse for some brands, integration in an American grocery store means being “divorced from its cultural background.”
Read more (The New York Times)
Will fermentation be key to the future of the food industry? A third of food produced globally is thrown out, but an article in Forbes explores a promising solution — more companies are using fermentation as a way to decrease food waste.
A new Danish startup, Resauce, gives companies the resources to turn their food waste into fermented products. Their success stories include a farmer who made fermented onion paste and sauerkraut from excess onions and cabbages, and a vineyard owner who converted grapes into a honey-fermented grape syrup. Each producer then sold their product under their own brand.
Resauce founder Philip Bindesbøll said: “Now we can give companies an innovative product, financial benefits, as well as a positive sustainable story.”
Read more (Forbes)
“If there were a country whose cuisine excels in the realm of fermented foods, it’s Japan,” highlights an article in Discover Magazine. In Japan, hakkо̄ (which translates to “fermentation”) forms “the very basis of gastronomy in the island nation,” continues the article.
Tsukemono (pickles), miso (fermented soy bean paste), soy sauce, nattо̄ (fermented soy beans), katsuobushi (dried fermented bonito flakes), nukazuke (vegetables pickled in rice bran), sake and shōchū (liquor distilled from rice, brown sugar, buckwheat or barley) are all staples of traditional Japanese meals.
Nattо̄ in particular has been proven to lower obesity rates, boost levels of dietary fiber, protein, calcium, iron and potassium and reduce diastolic blood pressure.
Though the article highlights the few, limited studies on the effects of other fermented foods, it also noted how difficult it is to study them. There little money behind the study of traditional foods (outside of yogurt), and participants in any such research would need to be on the same diets and exercise programs in order to produce objective results. A study would also need to take place over multiple years — “the cost would be vast, the ethics questionable.”
Read more (Discover Magazine)
The Fermentation Association recently surveyed our community to better understand who has engaged with us, how their businesses are doing and to gauge the impact of the pandemic. We want to share the very interesting results.
A few qualifying comments first, however. This survey should not be interpreted as producing a profile of the fermented industry — it reached only those with whom we have connected since TFA was launched in 2017. This group is heavily weighted to Food and Beverage Producers and those in the Science, Health and Research fields. And, even as we note surprisingly high response rates below, the quantities of responses to certain questions were small and would not meet standard analytical thresholds of statistical significance. So please treat the comments and conclusions that follow as directional rather than definitive.
We received 450 full or partial responses — nearly twice the number we had expected and what we would have considered “good.” Not surprisingly, the bulk of these were from Food and Beverage Producers — just under half — with a strong representation of the Science, Health and Research community, a little less than one-fifth. The balance of the respondents were classified as Supplier or Service Provider (9%); Chef/Writer/Educator (8%); Retailer/Distributor/Broker (3%); Food Service/Hospitality (3%); or fell into a miscellaneous Other category (12%).
We will be presenting further analyses and follow-up discussions in the coming weeks. This article focuses on the two largest segments: first, Food & Beverage Producers; then, Science, Health, and Research.
FOOD & BEVERAGE PRODUCERS
- We found that over 80% of our Producers are small businesses with 25 or fewer employees, and 65% had 2020 sales of less than $500,000. That said, over 11% of the companies represented are toward the other end of the spectrum, with 100 or more on staff, and 13% with revenue of over $10 million.
- We reach a lot of Owners/Founders/Senior Executives, over 70% of respondents. The next most well-represented functional areas are Operations and Product Development.
- These businesses are spread across the developmental timeline — a little over 40% are selling at the local level, or earlier in their growth cycle (selling at farmers market or still in testing/pre-launch mode). Yet 45% are selling regionally, nationally or internationally.
- Retail is still the largest (45%) channel of sale for these producers, but Direct-to-Consumer (DTC) is just slightly behind at 40%, with the remaining 15% through Food Service/Hospitality.
- Sauerkraut/Kimchi, Pickles, Condiments/Sauces and Kombucha were the most frequently-listed product categories, each mentioned by more than 20% of the producers. Kefir, Vinegar/Shrubs, Wine and Miso also were mentioned often. Of the 25 product categories listed, we had respondents involved in every one — except poor, slimy, and unrepresented natto.
- Nearly half of producers selling at retail and/or DTC had sales gains in 2020 and another third maintained their revenues. Not surprisingly, nearly 40% of producers selling into food service saw sales take a hit — only 15% reported gains.
- The Covid-19 pandemic caused a host of issues for producers, though their prevalence seemed to vary depending on the size of the company. Among larger producers, over 90% had issues meeting demand, with the primary problems being shortages of raw materials, packaging and staff, as well as distribution delays. Fewer of the small producers reported issues, but their problems fell into the same categories. Financial difficulties were cited more often among small producers.
- Nearly 30% of producers took advantage of the government’s Payroll Protection Plan.
- This year appears to continue or build on the sales levels achieved in 2020 for most producers. Nearly 40% report first quarter 2021 sales at the same level as last year, and nearly 50% reported further increases. And producers are optimistic about continuing these trends, with a mere 5% anticipating sales declines.
- Most (nearly two-thirds) of responding producers did not participate in tradeshows and conferences, and therefore felt no business impact from show cancellations in 2020.
- The producers that did participate in events favored the Natural Products Expos, Fancy Food Shows and IFT Show. While some felt that they lost short-terms sales and their future growth was hurt by the shows being cancelled, nearly 30% noted that they saved money and time by not attending. Some of those savings were reinvested in increased marketing, DTC sales and virtual events.
- Interestingly, half of the producers plan to continue their involvement as events resume at the same level as before the pandemic, and fully one-third plan to increase activity.
- Looking ahead, producers see numerous challenges on the horizon, led by a need for expanded distribution. They expect many of the recent shortages to continue to challenge, compounded by production, facility and financial constraints. While Covid protocols and food safety concerns persist, they are joined by the need for product development, e-commerce skills, and consumer marketing
- The clearly-articulated top priority for producers is a better-educated consumer. When asked what would foster increased consumption of fermented foods and beverages, the top item for nearly 70% is consumer education as to the nature and benefits of fermentation. The next highest priorities all support this same goal — more research into health impact (+40%), greater familiarity with flavors of fermentation (+40%) and more exposure at retail (+30%).
SCIENCE, HEALTH & RESEARCH
- The bulk — nearly 75% — of these respondents work in an academic environment, with very small clusters in government and medical/health organizations. It’s a well-educated group, with over half holding doctorates, plus another quarter with Master’s degrees. Roles are split quite evenly into thirds — professors, science/technical support and students/postdocs.
- Over 60% of these respondents are looking into connections between fermentation and health; roughly half are specifically focused on gut health and the human microbiome. Overall, three-quarters are currently researching fermentation and fermented products. Their activities, though, span the full spectrum of product categories. All the key categories among our producers — Sauerkraut/Kimchi, Pickles, Condiments/Sauces, Kombucha and Kefir — were well-represented in research. But they were joined by meaningful work across the board — Yogurt, Beer, Cheese, Alternative Proteins, Koji, Wine, Sourdough, Tempeh, Tea — even Natto!
- Slightly more than a third of this group is involved with fermented alternative proteins – an important, emerging category.
- Funding for research showed more declines (30% of respondents) than gains (under 15%) over the last year. But half of our sample expects funding to increase in the coming 12-18 month.
- Our Science, Health & Research respondents were split in how they viewed the interest in fermentation research — 60% felt the focus was increasing, but the topic was not yet a top priority. Yet a third saw fermentation as a hot topic, with more emphasis and activity than ever.
- Respondents in this group shared the views of producers that the key activities that would drive increased consumption of fermented products are:
- Consumer education about fermentation
- More research into health benefits
- Greater consumer familiarity with fermented flavors
Cheffing is a second career for Jessica Alonzo. Originally a hospital administrator in Dallas, she liked the stability and the benefits, but wasn’t happy. She longed for the days around the kitchen table with her mom, cooking for large family gatherings — “I have such fond memories of food.” Hospital pay got her through culinary school, and then she joined the acclaimed Dallas restaurant FT33 as a line cook. It was there that she got introduced to fermentation.
“With fermentation, the transformation of ingredients is just insane,” Alonzo says. “Fermentation is not new, it’s something that we’ve been doing for thousands of years. It’s a lost art and now it’s starting to make a resurgence.”
Fermentation and whole food utilization are Alonzo’s specialty. Whole food utilization, the cooking technique of using the entire animal or produce, marries perfectly with fermentation. Instead of discarding food scraps, skilled chefs are using the byproducts in brines, condiments and sauces.
“I preserve with a purpose,” says Alonzo, a Texas native. “I’ve worked with farmers long enough to understand what works with their produce throughout the year and what doesn’t. I’ve harvested with them, I’ve worked on their land. It plays a big role in fermentation to know how to properly preserve what farmers are harvesting.”
Alonzo is the sous chef at Dallas-based Petra and the Beast, a James Beard Award semifinalist known for its seasonal tasting menu. She stepped back to part-time status this year and launched her own business, Native Ferments TX, a larder shop that sells local ferments and offers virtual fermentation classes. Below are highlights from TFA’s interview with Alonzo.
The Fermentation Association: Tell me where the idea for Native Ferments came from.
Jessica Alonzo: Misti (Norris, chef/owner at Petra and the Beast) and my husband really pushed me to do it. They were like “You have the drive, you have the knowledge — why not share that talent with others?” People are always messaging me on Instagram asking me about different fermentation methods, and now I can teach them through classes. I love fermentation, I’m just fascinated with it, and it’s just continuous learning for me. You feel like you never really learn everything with fermentation, there’s so many different types of cuisines and techniques.
TFA: Why is it so important to you to support local farmers through fermentation?
JA: With both Native Ferments and Petra and the Beast, I get to work with farmers and support them, which is really what I love doing. Noma is helping make fermentation popular again, opening people’s eyes to the fact that fermentation has been happening forever. Fermentation is not new, there’s a tradition to respect. It was done back in the day because of necessity, people had to figure out how to save their harvest, and fermentation made it so they’d have the nutrients from their harvest throughout the rest of the year.
During the pandemic, restaurant sales for farmers dropped off drastically. At Petra, we had one of our farmers come to us with like a hundred pounds of mushrooms they couldn’t sell and they were going to go bad. I preserved them and made mushroom conservas and dried and did all these things with it, and then we ended up selling some of the mushroom pickles and conservas. I don’t know if any other restaurant did that in Dallas. It forced us to be really creative with food.
On my website for Native Ferments, I have profiles of the main farmers I use. When I sell at farmers markets, I have a big board with their Instagram handles. It’s their livelihood, I don’t want any of their produce to go to waste or to compost, I want the community to enjoy it. The magic of fermentation is transforming these simple ingredients with the natural microbes around you. I’ve worked with many of these farmers long enough to know what type of technique works well to pickle or ferment. I want to help educate people and get them excited and spread the word about the farmers’ hard work.
TFA: Tell me more about whole food utilization.
JA: At Petra, Misti was more the meat charcuterie person. She knows how to utilize every part of a pig or an animal. My mind goes more to vegetables, which I think is why we make such a good team. It makes sense that whole food utilization and fermentation go hand-in-hand. It’s part of preserving. We may be prepping something for tasting and then we have like carrot scraps or like some sort of vegetable or fruit scraps and we’ll automatically turn that into a vinegar. Or we dehydrate our char and dehydrate skins and turn that into part of a seasoning for another dish. Or I’ve done like roots from spring onions, I’ll brine those or I’ve chopped them up and parts in a condiment. We try to be as low waste of a kitchen as possible.
I do that with my ferments here with Native Ferments, too. In my fennel kimchi, I use the entire part of the fennel in that fennel kimchi, the fronds, the stems, everything, and then if my ratios were a little different so I did have some fronds left over, I dehydrate those and make that into a powder and now i’m utilizing that powder into a cure that I’m using on carrots for vegetable charcuterie. Understanding flavor profiles, too, helps when you’re cross utilizing your larder.
TFA: So tell me what have been some of your favorite fermentation creations you’ve been working on lately.
JA: Vegetable charcuterie is pretty cool, I’ve gotten some local produce in different root vegetables and I’m working on different charcuteries with more whole utilization in the curing. So like using the fennel from powder for part of the cure with carrots. I’m doing some shiro shoyu for another chef here in town and gluten-free shoyu for myself. I just smoked some beets and I’m pickling them in a shio koji that I made with a half sour brine and some spring onions. I’m hoping it takes on a meaty, smoky-like brisket, I was really craving barbecue when I did it.
TFA: Why do you think fermentation has become such a bigger interest among chefs?
JA: I think chefs are understanding the importance of the different complexity that you get when you build with fermented food in your cuisine. When Misti and I create dishes at Petra, we always in every dish that we create have some sort of pickle or ferment. Whether it’s an actual fermented vegetable or it could be an amino sauce that I’ve made or a shoyu or using shio koji or something, you don’t get that same transformation just by sauteing vegetables. You see the transformation by marianating them in shio koji first or using a brine in your pasta sauce rather than using a lemon juice. That’s how you build on these complex flavors. Some chefs are really trying to understand that. Utilizing fermented foods in their cuisine, being more creative with their flavor profiles, that’s what we do.
TFA: What do you think is the future of fermentation?
JA: With the resurgence of fermentation, I think it’s going to be more accepted in every household. I would hope that it would be something that every household would have. My parents grew up in the ‘60s, when everything was in a can. We had our traditional Mexican food, but we also had those times where it was Americanized, like everything in a canned food. Fermentation, this really should be the norm. Consumers need to be more aware of how beneficial it is
Fermented foods are produced through controlled microbial growth — but how do industry professionals manage those complex microorganisms? Three panelists, each with experience in a different field and at a different scale — restaurant chef, artisanal cheesemaker and commercial food producer — shared their insights during a TFA webinar, Managing Fermented Food Microbes to Control Quality.
“Producers of fermented foods rely on microbial communities or what we often call microbiomes, these collections of bacteria yeasts and sometimes even molds to make these delicious products that we all enjoy,” says Ben Wolfe, PhD, associate professor at Tufts University, who moderator the webinar along with Maria Marco, PhD, professor at University of California, Davis (both are TFA Advisory Board members).
Wolfe continued: “Fermenters use these microbial communities every day right, they’re working with them in crocks of kimchi and sauerkraut, they’re working with them in a vat of milk as it’s gone from milk to cheese, but yet most of these microbial communities are invisible. We’re relying on these communities that we rarely can actually see or know in great detail, and so it’s this really interesting challenge of how do you manage these invisible microbial communities to consistently make delicious fermented foods.”
Three panelists joined Wolfe and Marco: Cortney Burns (chef, author and current consultant at Blue Hill at Stone Barns in New York, a farmstead restaurant), Mateo Kehler (founder and cheesemaker at Jasper Hill in Vermont, a dairy farm and creamery) and Olivia Slaugh (quality assurance manager at wildbrine | wildcreamery in California, producers of fermented vegetables and plant-based dairy).
Fermentation mishaps are not the same for producers because “each kitchen is different, each processing facility, each packaging facility, you really have to tune in to what is happening and understand the nuance within a site,” Marco notes. “Informed trial and error” is important.
The three agreed that part of the joy of working in the culinary world is creating, and mistakes are part of that process.
“We have learned a lot over the years and never by doing anything right, we’ve learned everything we know by making mistakes,” says Kehler.
One season at Jasper Hill, aspergillus molds colonized on the rinds of hard cheeses, spoiling them. The cheesemakers discovered that there had been a problem early on as the rind developed. They corrected this issue by washing the cheese more aggressively and putting it immediately into the cellar.
“For the record, I’ve had so many things go wrong,” Burns says. A koji that failed because a heating sensor moved, ferments that turned soft because the air conditioning shut off or a water kefir that became too thick when the ferment time was off. “[Microbes are] alive, so it’s a constant conversation, it’s a relationship really that we’re having with each and every one on a different level, and some of these relationships fall to the wayside or we forget about them or they don’t get the attention they need.”
Burns continues: “All these little safeguards need to be put in place in order for us to have continual success with what we’re doing, but we always learn from it. We move the sensor, we drop the temperature, we leave things for a little bit longer. That’s how we end up manipulating them, it’s just creating an environment that we know they’re going to thrive in.”
Slaugh distinguishes between what she calls “intended microbiology” — the microbes that will benefit the food you’re creating — and “unintended microbiology” — packaging defects, spoilage organisms or a contamination event.
Slaugh says one of the benefits of working with ferments at a large scale at wildbrine is the cost of routine microbiological analysis is lower. But a mistake is stressful. She recounted a time when thousands of pounds of food needed to be thrown out because of a contaminant in packaging from an ice supplier.
“Despite the fact that the manufacturer was sending us a food-grade or in some cases a medical-grade ingredient, the container does not have the same level of sanitation, so you can’t really take these things for granted,” Slaugh says.
Her recommendations include supplier oversight, a quality assurance person that can track defects and sample the product throughout fermentation and a detailed process flow diagram. That document, Slaugh advises, should go far beyond what producers use to comply with government food regulations. It should include minutiae like what scissors are used to cut open ingredient bags and the process for employees to change their gloves.
“I think this is just an incredible time to be in fermented foods,” Kehler adds. “There’s this moment now where you have the arrival of technology. The way I described being a cheesemaker when I started making cheese almost 20 years ago was it was like being a god, except you’re blind and dumb. You’re unleashing these universes of life and then wiping them out and you couldn’t see them, you could see the impacts of your actions, but you may or may not have control. What’s happened since we started making cheese is now the technology has enabled us to actually see what’s happening. I think it’s this groundbreaking moment, we have the acceleration of knowledge. We’re living in this moment where we can start to understand the things that previously could only be intuited.”
A diet high in fermented foods increases microbiome diversity, lowers inflammation, and improves immune response, according to researchers at Stanford University’s School of Medicine.The groundbreaking results were published in the journal Cell.
In the clinical trial, healthy individuals were fed for 10 weeks, a diet either high in fermented foods and beverages or high in fiber. The fermented diet — which included yogurt, kefir, cottage cheese, kimchi, kombucha, fermented veggies and fermented veggie broth — led to an increase in overall microbial diversity, with stronger effects from larger servings.
“This is a stunning finding,” says Justin Sonnenburg, PhD, an associate professor of microbiology and immunology at Stanford. “It provides one of the first examples of how a simple change in diet can reproducibly remodel the microbiota across a cohort of healthy adults.”
Researchers were particularly pleased to see participants in the fermented foods diet showed less activation in four types of immune cells. There was a decrease in the levels of 19 inflammatory proteins, including interleukin 6, which is linked to rheumatoid arthritis, Type 2 diabetes and chronic stress.
“Microbiota-targeted diets can change immune status, providing a promising avenue for decreasing inflammation in healthy adults,” says Christopher Gardner, PhD, the Rehnborg Farquhar Professor and director of nutrition studies at the Stanford Prevention Research Center. “This finding was consistent across all participants in the study who were assigned to the higher fermented food group.”
Microbiota Stability vs. Diversity
Continues a press release from Stanford Medicine News Center: By contrast, none of the 19 inflammatory proteins decreased in participants assigned to a high-fiber diet rich in legumes, seeds, whole grains, nuts, vegetables and fruits. On average, the diversity of their gut microbes also remained stable.
“We expected high fiber to have a more universally beneficial effect and increase microbiota diversity,” said Erica Sonnenburg, PhD, a senior research scientist at Stanford in basic life sciences, microbiology and immunology. “The data suggest that increased fiber intake alone over a short time period is insufficient to increase microbiota diversity.”
Justin and Erica Sonnenburg and Christopher Gardner are co-authors of the study. The lead authors are Hannah Wastyk, a PhD student in bioengineering, and former postdoctoral scholar Gabriela Fragiadakis, PhD, now an assistant professor of medicine at UC-San Francisco.
A wide body of evidence has demonstrated that diet shapes the gut microbiome which, in turn, can affect the immune system and overall health. According to Gardner, low microbiome diversity has been linked to obesity and diabetes.
“We wanted to conduct a proof-of-concept study that could test whether microbiota-targeted food could be an avenue for combatting the overwhelming rise in chronic inflammatory diseases,” Gardner said.
The researchers focused on fiber and fermented foods due to previous reports of their potential health benefits. High-fiber diets have been associated with lower rates of mortality. Fermented foods are thought to help with weight maintenance and may decrease the risk of diabetes, cancer and cardiovascular disease.
The researchers analyzed blood and stool samples collected during a three-week pre-trial period, the 10 weeks of the diet, and a four-week period after the diet when the participants ate as they chose.
The findings paint a nuanced picture of the influence of diet on gut microbes and immune status. Those who increased their consumption of fermented foods showed effects consistent with prior research showing that short-term changes in diet can rapidly alter the gut microbiome. The limited changes in the microbiome for the high-fiber group dovetailed with previous reports of the resilience of the human microbiome over short time periods.
Designing a suite of dietary and microbial strategies
The results also showed that greater fiber intake led to more carbohydrates in stool samples, pointing to incomplete fiber degradation by gut microbes. These findings are consistent with research suggesting that the microbiome of a person living in the industrialized world is depleted of fiber-degrading microbes.
“It is possible that a longer intervention would have allowed for the microbiota to adequately adapt to the increase in fiber consumption,” Erica Sonnenburg said. “Alternatively, the deliberate introduction of fiber-consuming microbes may be required to increase the microbiota’s capacity to break down the carbohydrates.”
In addition to exploring these possibilities, the researchers plan to conduct studies in mice to investigate the molecular mechanisms by which diets alter the microbiome and reduce inflammatory proteins. They also aim to test whether high-fiber and fermented foods synergize to influence the microbiome and immune system of humans. Another goal is to examine whether the consumption of fermented foods decreases inflammation or improves other health markers in patients with immunological and metabolic diseases, in pregnant women, or in older individuals.
“There are many more ways to target the microbiome with food and supplements, and we hope to continue to investigate how different diets, probiotics and prebiotics impact the microbiome and health in different groups,” Justin Sonnenburg said.
Other Stanford co-authors are Dalia Perelman, health educator; former graduate students Dylan Dahan, PhD, and Carlos Gonzalez, PhD; graduate student Bryan Merrill; former research assistant Madeline Topf; postdoctoral scholars William Van Treuren, PhD, and Shuo Han, PhD; Jennifer Robinson, PhD, administrative director of the Community Health and Prevention Research Master’s Program and program manager of the Nutrition Studies Group; and Joshua Elias, PhD.