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Biotics in animal and human nutrition

Episode 22: Biotics in animal and human nutrition

/in Podcast, Season Two /by Laura

Biotics in animal and human nutrition

 

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The Science, Microbes & Health Podcast 

This podcast covers emerging topics and challenges in the science of probiotics, prebiotics, synbiotics, postbiotics and fermented foods. This is the podcast of The International Scientific Association for Probiotics and Prebiotics (ISAPP), a nonprofit scientific organization dedicated to advancing the science of these fields.

Biotics in animal and human nutrition, with Prof. Kelly Swanson

Episode summary:

In this episode, the ISAPP podcast hosts join guest Prof. Kelly Swanson PhD from University of Illinois at Urbana-Champaign, to discuss the role of biotics in animal and human nutrition. They review the criteria for prebiotics and synbiotics, then discuss how we gain knowledge about nutrition and the role of biotics in animals compared to humans.

Key topics from this episode:

  • A good argument can be made that biotics are essential for our diet; they are beneficial even if efficacy is sometimes difficult to prove.
  • Nutrients have an impact on the host’s health and simultaneously on the host-associated microbes.
  • Health benefits are essential to the FDA definition of fiber.
  • Antibiotics’ effect on the microbiota: short-term effects may be minor, but we still don’t know the long-term effects.
  • The synbiotics definition, criteria for products to meet this definition, and the health outcomes from using these biotic substances.
  • The difference between complementary and synergistic synbiotics.
  • When studying biotics in companion animals (cats and dogs), can results from one host be extrapolated to another host? Final studies should be in the target host.
  • Biotics are important in veterinary medicine and a popular topic of study.
  • Predictions about the future of nutrition science as informed by the microbiome.

Episode links:

Additional resources:

About Prof. Kelly Swanson:

Kelly Swanson is the Kraft Heinz Company Endowed Professor in Human Nutrition at the University of Illinois at Urbana-Champaign. His laboratory studies the effects of nutritional interventions, identifying how diet impacts host physiology and gut microbiota. His lab’s primary emphasis is on gastrointestinal health and obesity in dogs, cats, and humans. Much of his work has focused on dietary fibers and ‘biotics’. Kelly has trained over 40 graduate students and postdocs, published over 235 peer-reviewed manuscripts, and given over 150 invited lectures at scientific conferences. He is an active instructor, teaching 3-4 nutrition courses annually, and has been named to the university’s ‘List of Teachers Ranked as Excellent by Their Students’ 30 times. He serves on advisory boards for many companies in the human and pet food industries and non-profit organizations, including the Institute for the Advancement of Food and Nutrition Sciences and International Scientific Association for Probiotics and Prebiotics.

Can diet shape the effects of probiotics or prebiotics?

/in Consumer Blog, ISAPP Science Blog /by KC

By Prof. Maria Marco PhD, University of California – Davis and Prof. Kevin Whelan PhD, King’s College London

If you take any probiotic or prebiotic product off the shelf and give it to several different people to consume, you might find that each person experiences a different effect. One person may notice a dramatic reduction in gastrointestinal symptoms, for example, while another person may experience no benefit. On one level this is not surprising, since every person is unique. But as scientists, we are interested in finding out exactly what makes a person respond to a given probiotic or prebiotic to help healthcare providers know which products to recommend to which people.

Among factors that might impact someone’s response to a probiotic or prebiotic – such as baseline microbiota, medications, and host genetics – diet emerges as a top candidate. Ample evidence has emerged over the past ten years that diet has direct and important effects on the structure and function of the gut microbiome. Overall the human gut microbiome is shaped by habitual diet (that is, the types of foods consumed habitually over time), but the microbes can also can fluctuate in response to short-term dietary shifts. Different dietary patterns are associated with distinct gut microbiome capabilities. Since probiotics and prebiotics may then interact with gut microbes when consumed, it is plausible that probiotic activity and prebiotic-mediated gut microbiome modulation may be impacted by host diet.

A discussion group convened at ISAPP’s 2022 annual meeting brought together experts from academia and industry to address whether there is evidence to support the impact of diet on the health effects of probiotics and prebiotics. To answer this question, we looked at how many probiotic or prebiotic studies included data on subjects’ diets.

  • Prebiotics: Our review of the literature showed that only a handful of prebiotic intervention studies actively measured background diet as a potential confounder of the effect of the prebiotic. One such study (Healey, et al., 2018) classified individuals based on habitual fiber intake, and in doing so found that the gut microbiome of individuals consuming high fiber diets exhibited more changes to microbiome composition than individuals with low fiber intake. While both groups consuming prebiotics showed enrichment of Bifidobacterium, those with high fiber intake uniquely were enriched in numerous other taxa, including butyrate-producing groups of microbes. Prebiotics also resulted in improved feelings of satiety, but only among the high fiber diet consumers.
  • Probiotics: We found no evidence of published human RCTs on probiotics that investigated diet as a possible confounding factor. This is a significant gap, since we know from other studies that host diet affects the metabolic and functional activity of probiotic lactobacilli in the digestive tract. Moreover, the food matrix for the probiotic may further shape its effects, via the way in which the probiotic is released in situ.

Our expert group agreed that diet should be included in the development of new human studies on probiotics and prebiotics, as well as other ‘-biotics’ and fermented foods. These data are urgently needed because although diet may be a main factor affecting outcomes of clinical trials for such products, it is currently a “hidden” factor.

We acknowledge there will be challenges in taking diet into account in future trials. For one, should researchers merely record subjects’ habitual dietary intake, or should they provide a prescribed diet for the duration of the trial? The dietary intervention (nutrient, food, or whole diet) must also be clearly defined, and researchers should carefully consider how to measure diet (e.g. using prospective or retrospective methods). In the nutrition field, it is well known that there are challenges and limitations in the ways dietary intake is recorded as well as the selection of dietary exclusion criteria. Hence, it is crucial that dietitians knowledgeable in dietary assessment and microbiome research contribute to the design of such trials.

If more probiotic and prebiotic trials begin to include measures of diet, perhaps we will get closer to understanding the precise factors that shape someone’s response to these products, ultimately allowing people to have more confidence that the product they consume will give them the benefits they expect.

New ISAPP Webinar: Fermented Foods and Health — Continuing Education Credit Available for Dietitians

/in News /by KC

Dietitians – along with many other nutritional professionals – often receive questions about consuming fermented foods for digestive health. But how strong is the evidence that fermented foods can improve digestive health?

ISAPP is pleased to work with Today’s Dietitian to offer a free webinar in which Hannah Holscher, PhD, RD, and Jennifer Burton, MS, RD, LDN will discuss the foundational elements of fermented foods, the role of microbes in fermentation, how they differ from probiotics and prebiotics, and how to incorporate fermented foods into client diets in an evidence-based manner. Participants will come away with a grasp of the scientific evidence that supports fermented food consumption. This activity is accredited by the Academy of Nutrition and Dietetics Commission on Dietetic Registration (CDR) for 1.0 CPEUs for dietitians.

The one-hour virtual event, titled “Fermented Foods and Health — Does Today’s Science Support Yesterday’s Tradition?”, was held April 20th, 2022, at 2:00 pm Eastern Time.

See the webinar recording here.

ISAPP and Today’s Dietitian also collaborated on a self-study activity titled “Evidence-based use of probiotics, prebiotics and fermented foods for digestive health”. This free activity, which provides more detail on the topic that the 1-hour webinar above, was approved by CDR to offer 2.0 CPEUs for dietitians and is available here through November 2023.

Do fermented foods contain probiotics?

/in Consumer Blog, ISAPP Science Blog /by KC

By Prof. Maria Marco, PhD, Department of Food Science & Technology, University of California, Davis

We frequently hear that “fermented foods are rich in beneficial probiotics.” But is this actually true? Do fermented foods contain probiotics?

The quick answer to this question is no – fermented foods are generally not sources of probiotics. Despite the popular assertion to the contrary, very few fermented foods contain microbes that fit the criteria to be called probiotic. But this fact does not mean that fermented foods are bad for you. To uphold the intent of the word probiotic and to explain how fermented foods actually are healthy, we need to find better ways to describe the benefits of fermented foods.

Probiotics are living microorganisms, that when administered in adequate amounts, confer a health benefit on the host (Hill et al 2014 Nat Rev Gastroenterol Hepatol). This current definition reflects minor updates to a definition offered by an expert consultation of scientists in 2001 convened by the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization. Evident from the definition, a microbial strain is not a probiotic unless a health benefit has been found with its use. At a minimum, the strain should be proven to be beneficial in at least one randomized controlled trial (RCT). Probiotics must also be defined at the strain level through genome sequencing (a strain is a single genotype of a species).

Fermented foods, on the other hand, have no requirement to improve health. Fermented foods are foods and beverages made through desired microbial growth and enzymatic conversion of food components. This definition was recently formulated by an ISAPP consensus panel of scientific experts to affirm the common properties of all foods of this type and to differentiate foods that may look or taste similar but are not made using microbes (Marco et al 2021 Nat Rev Gastroenterol Hepatol). Fermented foods encompass an expansive variety of foods made from animal and plant sourced ingredients and produced from all types of microbial metabolism. The desired characteristics of these foods are frequently how they look, smell, and taste. There no expectation in this definition that fermented foods alter health in any way.

There is also no requirement for fermented foods contain living microbes at the time they are ingested. Foods such as bread, chocolate, and beer are fermented but then are baked, roasted, and/or filtered. This means those fermented foods cannot be probiotic.

Some fermented foods, such as kimchi and kombucha, are typically eaten with living microbes present. However, the microbes in those foods usually do not meet the criteria to be called probiotic. Whether the fermented food was made at home or purchased from the supermarket, studies investigating whether the microbes in those fermented foods are specifically responsible for a health benefit remain to be done. Those foods also do not contain microbes defined to the strain level, nor is the number of living microbes typically known. An exception to this is if specific strains previously shown to provide a health benefit in one or more RCT are intentionally used in the production of the food and remain viable at expected numbers over the shelf-life of that fermented food product. An example of this would be a commercial fermented yogurt that has an added probiotic strain remaining viable at the time of consumption, beyond the strains that carried out the fermentation.

Despite these distinctions between probiotics an fermented foods, the probiotics term has pervaded common lexicon to mean “beneficial microbes”. In contrast to pathogenic or harmful microbes, beneficial microbes are those that are understood to help rather than hurt bodily functions. However, just as we do not assume that all pathogens cause the same disease or result in the same severity of symptoms, we should also not expect that beneficial microbes all serve the same purpose. By analogy, automobiles are useful vehicles which help us to get from place to place. We do not expect that all automobiles perform like those used for Formula 1 racing. Microbes are needed to make fermented foods and may be beneficial for us, but we should not assume that those drive health benefits like established probiotic strains.

What are the consequences of calling fermented foods probiotic when they include undefined numbers of living microbes for which strain identities are not known? One can suppose that there is no harm in labeling or describing those products as “probiotic” or “containing probiotics”. However, by doing so, confusion and misunderstanding is created and too often, spread by journalists, nutritionists, scientists, and medical professionals. For example, news articles in reputable sources have written that foods like kefir, kimchi, sauerkraut made from beets or cabbage, pickles, cottage cheese, olives, bread and chocolate are rich in probiotics. As misuse perpetuates, what becomes of bona fide probiotics shown with rigorous study to benefit health, such as reducing the incidence and duration of diarrhea or respiratory infections? It becomes difficult to know which strains have scientific proof of benefit. Just as there are laws for standards of food identity, we should strive to do the same when describing microbes in fermented foods.

Avoiding the term probiotic when describing fermented foods should not stop us from espousing the myriad of positive attributes of those foods. Besides their favorable sensory qualities, fermented foods are frequently safer and better tolerated in the digestive tract than the foods they are made from. During the production of fermented foods, microbes remove or reduce toxins in the ingredients and produce bioactive compounds that persist long after the microbes that make them are gone.

Even though the living microbes in fermented foods may not rise to the standard of a probiotic, they may provide health benefits. We just don’t have the studies to prove that they do. With more study, we may find that viable microbes in fermented foods work similarly to probiotics in the digestive tract through shared mechanisms. This is already known for yogurts. Yogurt cultures share the ability to deliver lactase to the intestine, thereby improving tolerance of lactose by intolerant individuals. Clinical and epidemiological studies performed on fermented foods already suggest an association between them and different health benefits but as we recently explained (Marco et al 2021 J Nutrition), more work is needed in order to understand if and what benefits these microbes provide.

For now, we should simply continue enjoying the making and eating of fermented foods and reserve the term probiotics for those specific microbial strains which have been shown to improve our health. Marketers should resist labeling products as containing probiotics if their products do not meet the criteria for a probiotic. Indeed, the descriptor “live and active cultures” more accurately reflects the microbial composition of many fermented foods, and should be used until controlled human trials demonstrating health benefits are conducted.

 

Additional resources:

How are probiotic foods and fermented foods different? ISAPP infographic.

Fermented foods. ISAPP infographic.

What are fermented foods? ISAPP video.

Are fermented foods probiotics? Webinar by Mary Ellen Sanders, PhD.

 

Can fermented or probiotic foods with added sugars be part of a healthy diet?

/in Consumer Blog, ISAPP Science Blog /by KC

By Dr. Chris Cifelli, Vice President of Nutrition Research, National Dairy Council, Rosemont IL, USA

What about added sugar in fermented or probiotic foods? I am almost always asked this question whenever I give a nutrition presentation, no matter the audience. It’s not a surprising question as people care about what they eat and, often, are looking for ways to reduce their intake of sugar. Yet, if someone wants to add fermented or probiotic foods such as yogurt, kefir or kombucha to their diet, they often find the products available to them contain sugar as an added ingredient.

Should these products be part of you and your family’s healthy eating plan even if they have added sugar? The simple answer – yes, they likely can still fit into a healthy eating plan.

According to the U.S. Food and Drug Administration, ‘added sugars’ are defined as sugars that are either added during the processing of foods or are packaged separately as sugars (e.g. the bag of sugar you buy to make your treats). Added sugars in the diet have received attention because of their link to obesity and chronic disease risk. The World Health Organization, American Heart Association, Dietary Guidelines for America, and American Diabetes Association all recommend reducing added sugar intake to improve overall health. While data from the US National Health and Nutrition Examination Survey (NHANES) has shown that consumption of added sugar decreased from the 2007-2010 to the 2013-2017 surveys, the most recent Dietary Guidelines Advisory Committee report noted that the mean usual consumption of added sugars was still 13% of daily energy in 2015-16, which exceeds recommendations of 10%.

Including fermented foods in one’s diet may be important for overall health. The recent ISAPP consensus paper on fermented foods indicated that fermented foods, especially the live microbes contained in them, could benefit health in numerous ways, such as by beneficially modulating the gut microbiota or the immune system. Similarly, foods with added probiotics may confer health benefits ranging from impacting digestive health to metabolic parameters, depending on the probiotic contained in the product. Our understanding of the gut microbiota continues to evolve, but one thing is for certain: it is important for health. This provides a compelling reason to find ways to include these foods in healthy eating patterns.

So, back to the question at hand. Should you reduce or eliminate fermented foods and foods with probiotics from your diet if they have added sugars? Just like a “spoonful of sugar helps the medicine go down,” a little added sugar to improve the palatability of nutrient-dense foods is okay. Indeed, government and health organizations all agree that people can eat some sugar within the daily recommendations (which is 10% of total daily calories), especially in foods like yogurt or whole-grain cereals, or other healthy foods. And, there is no scientific evidence to show that the sugar in these products reduces the health benefits associated with eating foods like yogurt or probiotics. Human studies assessing health benefits of probiotic foods typically use products with added sugar, yet health effects are still observed.

The next time you are out shopping you can choose your favorite fermented or probiotic-containing food guilt free, as long as you’re watching your overall daily intake of sugar. But, if are you are still concerned, then choose plain varieties to control your own level of sweetness or you could opt for a probiotic supplement to avoid the sugar. Whether you go with the sweetened or unsweetened version of your favorite fermented food, you’ll not only get the benefit of the live microbes in these products but also the nutritional benefit that comes with foods like yogurt.

 

Ambient yogurts make a global impact

/in Consumer Blog, ISAPP Science Blog /by KC

By Prof. Bob Hutkins, PhD, University of Nebraska Lincoln, USA

Quick, which country consumes the most yogurt? Must be France? Or the Netherlands? Maybe Turkey? The United States, perhaps? Try none of the above: the answer is China.

While many other countries consume way more yogurt than China on a per capita basis, China’s population gives it an advantage, with 1.4 billion potential consumers. And yogurt has become one of the most popular snack foods in China. It’s especially trendy among young and affluent urbanites. Indeed, total consumption of yogurt in China now exceeds that of France, the Netherlands, Turkey, and the United States, combined!

Whereas per capita consumption of yogurt in China in 2000 was around 1 kg per person per year, it’s now approaching 5 kg. Yogurt consumption even exceeds that of fluid milk.

Considering that dairy consumption was virtually non-existent in China for thousands of years, this trend is nothing short of a cultural phenomenon. While some of the yogurt consumed in the country is produced by domestic manufacturers, yogurt and yogurt ingredients are also being imported from other countries in the region, including New Zealand and Australia.

There is, however, one major difference between yogurt typically consumed in China and the products consumed in other regions. Indeed, ambient yogurt, short for “yogurt-based product for ambient distribution”, is all the rage in China.

Ambient yogurt and yogurt drink products, as the name implies, are stable at room temperature. This is achieved by heat-treating the yogurt after fermentation.  Many ambient yogurts are aseptically processed similar to ultra-high-temperature processed (UHT) products, leaving the product commercially sterile (i.e. without live microbes) and stable for up to a year. In China, these products can still be labeled as yogurt.

Not only are these ambient yogurt products convenient for retailers, but also, a cold-chain infrastructure, often absent in rural areas of China, is not necessary during transport and distribution. Perhaps for this reason, ambient yogurts are also being introduced in other regions, including Africa, South America, and the Middle East.

The popularity of yogurt in China, in the absence of a live microbe label declaration, is evidently due to the ‘healthy’ virtues or halo effect ascribed to yogurt, because of its high protein, calcium, and vitamin content. Perhaps there are also postbiotic benefits in the yogurt – this would be an interesting topic for research. But the novel flavors, textures and grab-and-go convenience, especially for drinkable yogurt products, also appeals to teens and young adults.

Traditionalists balk at the very idea of heat-treating yogurt and inactivating the live microorganisms. In some countries, such products cannot even be labeled as yogurt. In the U.S., these products can be labeled as yogurt but must be further labeled as “heat-treated”.

In reality, consumers’ expectation of live microbes in yogurt is so ingrained that heat-treated yogurts are nearly impossible to find in the United States. Indeed, yogurt, kefir, and other cultured milk and non-dairy products are promoted, in part, on the high number of viable microbes they contain. Probiotics are added to more than 90% of the yogurts sold in the United States.

According to international CODEX standards, yogurt must be made with Lactobacillus delbrueckii subsp. bulgaricus and Streptococcus thermophilus, AND must contain at least 107 CFU/g “through to the date of minimum durability after the product has been stored under the storage conditions specified in the labeling”. Any other labeled bacteria must be present at a minimum of 106 CFU/g. The CODEX standards have been widely adopted, although some countries have lower minimum levels.

Interestingly, and despite appeals by yogurt manufacturers, the U.S. Food and Drug Administration does not require minimum numbers of CFUs for yogurt. They have been considering changes that would be consistent with CODEX for more than a decade. In regions that do not require the CODEX standards, the International Dairy Foods Association offers the Live & Active Cultures (LAC) seal, which requires 107 CFU/g of yogurt cultures at time of manufacture.

The China National Food Safety Standard for Fermented Foods does specify a minimum Lactobacillus count of 106 CFU/g, but importantly, also includes the following footnote:

“products that have gone through heat treatment after the fermentation process will not be subjected to any requirements on the minimum Lactobacillus Count”

Such products, however, must be labeled as heat-treated. It should be noted that there is still a substantial market for more traditional (chilled) yogurt containing live microorganisms.  Still, ambient yogurts account for most of the yogurt consumed in China.

Given the relatively flat yogurt market in Europe and the United States, it should not be surprising that this rapidly growing market in China has attracted so much attention.  The China Nutrition Society and government policymakers have recommended that consumers increase dairy consumption to 3 times higher than current levels. That means a lot more yogurt will be consumed in China.

Translated, that means, from culture companies to processing and packaging industries, there will continue to be plenty of interest, innovation, and investment in yogurt for the Chinese population. For example, new generation yogurt products have recently been introduced with the claim of having 90 days’ shelf-life and containing live probiotic bacteria.

Still, whether by new or traditional technologies, the availability and consumption of live microbes in yogurt and other cultured products may be expected to increase as Chinese consumers become more informed about their health benefits. Perhaps, as cold-chain infrastructure also improves, these live yogurts may become a bigger part of the yogurt culture in China.

 

New ISAPP-led paper calls for investigation of evidence for links between live dietary microbes and health

/in ISAPP Science Blog, Consumer Blog /by KC

The past two decades have brought a massive increase in knowledge about the human gut microbiota and its links to human health through diet. And although many people perceive that regular consumption of safe, live microbes will benefit their health, the scientific evidence to date has not been sufficiently developed to justify adding a daily recommended intake of live microbes to food guides for different populations.

Recently, a group of seven scientists, including six ISAPP board members, published their perspective about the value of establishing the link between live dietary microbes and health. They conclude that although the scientific community has a long way to go to build the evidence base, efforts to do this are worthwhile.

The collaboration on this review was rooted in an ISAPP expert discussion group held at the 2019 annual meeting in Antwerp, Belgium. During the discussion, various experts presented evidence from their fields—addressing the potential health benefits of live microbes in general, rather than the narrow group of microbial strains that qualify as probiotics.

Below, the authors of this new review answer questions about their efforts to quantify the relationship between greater consumption of live microbes and human health.

Why is it interesting to look at the potential importance of live microbes in nutrition?

Prof. Joanne Slavin, PhD, RD, University of Minnesota

Current recommendations for fiber intake are based on protection against cardiovascular disease—so can we do something similar for live microbes? We know that intake of live microbes is thought to be health promoting, but actual recommended intakes for live microbes are missing.  Bringing together a talented group of microbiologists, epidemiologists, nutritionists, and food policy experts moves this agenda forward.

Humans need proper nutrition to survive, and a lack of certain nutrients creates a ‘deficiency state’. Is this the case for live microbes?

Dr. Mary Ellen Sanders, PhD, ISAPP Executive Science Officer

I don’t think we’ll find that live microbes are essential in the same way that vitamins and minerals lead to deficiency diseases. After all, gnotobiotic animal colonies are viable. But I believe there is enough evidence to suggest that consumption of live microbes will promote health. Exactly how and to what extent remains to be established.

Why think about intake of ‘live microbes’ in general, rather than intake of probiotic & fermented foods specifically?

Prof. Maria Marco, PhD, University of California Davis

We are constantly exposed to microorganisms in our foods and beverages, in the air, and on the things we touch. While much of our attention has been on the microbes that can cause harm, most of our microbial exposures may not affect us at all or, quite the opposite, be beneficial for maintaining and improving health. Research on probiotic intake as a whole supports this possibility. However, probiotic-containing foods and dietary supplements are only a part of our dietary connection with live microbes. Non-pasteurized fermented foods (such as kimchi and yogurts) can contain large numbers of non-harmful bacteria (>10^7 cells/g). Fruits and vegetables are also sources of living microbes when eaten raw.  Although those raw foods they may contain lower numbers of microbes, they may be more frequently eaten and consumed in larger quantities. Therefore, our proposal is that we take a holistic view of our diets when weighing the potential significance of live microbe intake on health and well-being.

What are dietary sources of live microbes? And do we get microbes in foods besides fermented & probiotic foods?

Prof. Bob Hutkins, PhD, University of Nebraska Lincoln

For tens of thousands of years, humans consumed large amounts of microbes nearly every time they ate food or drank liquids. Milk, for example, would have been unheated and held at ambient temperature with minimal sanitation and exposed to all sorts of microbial environments.  Thus, a cup of this milk could easily have contained millions of bacteria. Other foods like fruits and vegetables that were also exposed to natural conditions could have also contained similar levels of microbes. Even water would have contributed high numbers of live microbes.

Thanks to advances in food processing, hygiene, and sanitation, the contemporary western diet generally contains low levels of microbes. Consider how many foods we eat that are canned, pasteurized, or cooked – those foods will contain few, in any live microbes. Fresh produce can serve as a source of live microbes, but washing, and certainly cooking, will reduce those levels.

For sure, the most reliable sources of dietary microbes are fermented foods and beverages. Even if a fresh lettuce salad were to contribute a million bacteria, a single teaspoon of yogurt could contain 100 times more live bacteria. Other popular fermented foods like kefir, kimchi, kombucha, and miso, can contain a large and relatively diverse assortment of live microbes. Other fermented foods, such as cheese and sausage, are also potential sources, but the levels will depend on manufacturing and aging conditions. Many fermented, as well as non-fermented foods are also supplemented with probiotics, often at very high levels.

What’s the evidence that a greater intake of live microbes may lead to health benefits?

Prof. Dan Merenstein, MD, Georgetown University

Studies have shown that fermented foods are linked to a reduced risk of cardiovascular disease, reduced risk of weight gain, reduced risk of type 2 diabetes, healthier metabolic profiles (blood lipids, blood glucose, blood pressure and insulin resistance), and altered immune responses. This link is generally from associative studies on certain fermented foods. Many randomized controlled trials on specific live microbes (probiotics and probiotic fermented foods) showing health benefits have been conducted, but randomized controlled trials on traditional fermented foods (such as kimchi, sauerkraut, kombucha) are rare. Further, no studies have aimed to assess the specific contribution of safe, live microbes in diets as a whole on health outcomes.

Why is it difficult to interpret past data on people’s intake of live microbes and their health?

Prof. Colin Hill, PhD, University College Cork

It would be wonderful if there were a simple equation linking the past intake of microbes in the diet and the health status of an individual (# MICROBES x FOOD TYPE = HEALTH). In reality, this is a very complex challenge. Microbes are the most diverse biological entities on earth, our consumption of microbes has not been deliberately recorded and can only be estimated, and even the concept of health has defied precise definitions for centuries. To further confuse the situation microbes meet the host in the gastrointestinal tract, the site of our enormously complex mucosal immune system and equally complex microbiome.  But the complexity of the problem should not prevent us from looking for prima facie evidence as to whether or not such a relationship is likely to exist.

Databases of dietary information have data on people’s intake of live microbes, but what are the limitations of our available datasets?

Prof. Dan Tancredi, PhD, University of California Davis

Surveys often rely on food frequency questionnaires or diaries to determine consumption of specific foods. These are notoriously prone to recall error and/or other types of measurement error. So, even just measuring consumption of foods is difficult. For researchers seeking to quantify survey respondents’ consumption of live microbes, these challenges become further aggravated because the respondents would not typically know the microbial content in the foods they consumed. Instead, we would have to have them tell us the types and amounts of the foods they ate, and then we would need to translate that into approximate microbial counts—but even within a particular food, the microbial content can vary, depending on how it was processed, stored, and/or prepared prior to consumption.

See ISAPP’s press release on this paper here.

Update on harmonized guidelines for probiotics being developed by the Codex Alimentarius

/in ISAPP Science Blog, News /by KC

By Prof. Gabriel Vinderola, PhD,  Associate Professor of Microbiology at the Faculty of Chemical Engineering from the National University of Litoral and Principal Researcher from CONICET at Dairy Products Institute (CONICET-UNL), Santa Fe, Argentina

In December 2017, at the 39th session of the Codex Committee on Nutrition and Foods for Special Dietary Uses (CCNFSDU) in Berlin, members of the Committee agreed to include in the agenda a discussion of harmonized guidelines on probiotics for use in foods and food supplements. Argentina supported this initiative and proposed itself to lead the work, building a guideline based on the present Argentinian framework on probiotics.

The first draft of the document was presented in 2018. Some countries supported the work to develop harmonized guidelines with a definition and minimum requirements for characterization, quality, and labeling, while other countries did not support the initiative, arguing that there was no perceived need to start this new work, it was not a priority for the Committee at that moment, and the document should be revised to provide more clarity on the need to start work on this topic.

Early in 2019, Argentina convened a panel of local experts to contribute to the discussion of the paper based on the issues raised in the first round of revision. I participated in that panel.

In November 2019, at the 41th meeting of the CCNFSDU, an updated version of the paper was presented. This revision clarified that the goal of the work was to produce a regulatory framework for the use of probiotics in food and food supplements. This objective is in line with the purpose of the Codex Alimentarius to guarantee safe and quality food and to ensure equity in international food trade.

In the course of the debate, some delegations favored the topic, stressing the value of regulatory harmonization within the Codex. They pointed out that framework could be based on the existing probiotic definition and guidelines of FAO and WHO, providing clear guidance and principles focused on the use of probiotics as ingredients. Delegations that opposed the new work noted that the Codex had already adopted principles and guidelines of a similar (horizontal) nature on issues such as labeling, claims, contaminants, safety and hygiene covering all foods, including food supplements, and that probiotic-specific regulations were not needed. FAO and WHO had also conducted work in this area.

After the debate, the Committee considered that the document presented needed further clarification, especially with regard to the scope and the issues raised in the discussion. Finally, it was agreed that Argentina and Malaysia would revise the document to be presented at the next plenary meeting of the Committee (42th meeting), to be held in November 2020. It was agreed that in order to assess the need to work on this topic, the new proposal should include a justification for additional probiotic-specific criteria in accordance with the mechanism for assigning Committee priorities.

Due to the COVID-19 pandemic, the 42th meeting has been postponed until November 2021, and a deadline of March 2021 was set for submitting the revised paper to the CCNFSDU.

The information reported in this post was kindly provided by Andrea Moser, Argentinian representative at the Codex Committee on Nutrition and Foods For Special Dietary Uses.

 

Locally produced probiotic yogurt for better nutrition and health in Uganda

/in Consumer Blog, News /by KC

By Prof. Seppo Salminen, Director of Functional Foods Forum, University of Turku, Turku, Finland

Can locally produced probiotic yogurt be a way to increase the health and wealth of people in resource-poor areas of Uganda? Recently Dr. Nieke Westerik, a researcher from the Netherlands, partnered with a local Ugandan team to explore a yogurt production and distribution program similar to one that had previously proved successful in low-income areas of Argentina.

Since 2008, “Yogurito Social Program” has been operating in Argentina and now some 350,000 schoolchildren in less developed provinces enjoy the benefits of daily probiotic yogurt developed locally. Dr. Westerik (Free University of Amsterdam and Yoba 4 Life Foundation), with support from former ISAPP board member Prof. Gregor Reid, has now helped adapt the program to local needs in Uganda, making use of a well-known probiotic (Lacticaseibacillus rhamnosus GG) plus a yogurt starter (produced by the Yoba 4 Life Foundation) for production of the yogurt. The probiotic’s health effects have been demonstrated in human intervention studies.

The team worked on technical training and quality control of the locally produced yogurt, developing a production protocol suitable for Ugandan small-scale manufacture of probiotic fermented foods. Dr. Westerik’s team then conducted two clinical studies that demonstrated that the consumption of this probiotic product improved natural defenses and prevented respiratory infections (e.g. the common cold) and intestinal infections, which are the infectious conditions of greatest relevance in childhood in Uganda.

Yogurt is a new tool for individuals in developing areas of Uganda to achieve better health through diet, with potentially significant social and economic implications. Both the Ugandan and Argentinian experiences illustrate the power of microbes to positively impact the lives of women, men, and children. Given the positive results from these two different contexts, such activities could be replicated in other geographical areas—with either dairy, vegetable, or grain fermentations used locally with defined, well-studied starter cultures.

Further reading:

Julio Villena, Susana Salva, Martha Núñez, Josefina Corzo, René Tolaba, Julio Faedda, Graciela Font and Susana Alvarez. Probiotics for Everyone! The Novel Immunobiotic Lactobacillus rhamnosus CRL1505 and the Beginning of Social Probiotic Programs in Argentina. International Journal of Biotechnology for Wellness Industries, 2012, 1, 189-198.

Westerik N. 2020. Locally produce probiotic yoghurt for better nutrition and increased incomes in Uganda. PhD thesis, Free University of Amsterdam, The Netherlands.

Reid G, Kort R, Alvarez S, Bourdet- Sicard R, Benoit V, Cunningham M,  Saulnier DM, van Hylckama  Vlieg JET, Verstraelen H, Sybesma W.  Expanding the reach of probiotics through social enterprises. Beneficial Microbes, 9 (5): 707-715.

YOGURITO –the Argentinian social program with a special yogurt

 

 

 

Opportunity for research grants to help understand evidence linking live dietary microbes and health

/in News, ISAPP Science Blog /by KC

For thousands of years, cultures across the globe have been consuming fermented foods, many of which contain diverse and numerous live microbes. Yet scientists are still puzzling over whether a greater intake of live microbes results in measurably better health. As part of long-term efforts to understand evidence for the health benefits of live dietary microbes and identify research gaps, ILSI North America is presenting a grant opportunity for researchers to help assess current scientific evidence for these links.

Researchers are invited to submit grant proposals, which should include the research approach along with anticipated challenges, resources, timeline, and key deliverables. The ILSI North America Gut Microbiome Committee also requests the inclusion of a suggested publication plan for the work. Budgets in the range of $100-150K will be considered. The deadline to submit the proposal is October 30, 2020 at 11:59PM EST. See here for more details.

ISAPP is supporting long-term efforts in this topic area. Its latest effort is the publication of a review paper (in press) on the links between dietary live microbes and health, called Should there be a recommended daily intake of microbes? The paper is authored by ISAPP board members Prof. Maria Marco, Prof. Colin Hill, Prof. Bob Hutkins, Prof. Dan Tancredi, Prof. Dan Merenstein, and Dr. Mary Ellen Sanders along with well-known nutrition researcher, Prof. Joanne Slavin.

ILSI North America is a non-profit scientific organization whose mission is to advance food safety and nutrition science for the benefit of public health. The organization engages academic, government, and industry experts by conducting­ research projects, workshops, seminars, and publications.

 

bowl of yogurt with strawberries

Advice from a Nutritionist:  Eat More Fermented Foods.

/in Consumer Blog, featured, ISAPP Science Blog /by Mary Ellen Sanders

September 2017. By Christopher Cifelli, PhD, VP of Nutrition Research, National Dairy Council.

Whenever I tell someone that I have a degree in nutrition science, I usually get asked, “Are carbs bad?” or “Should I avoid added sugars?” Rarely do I get asked “What should I be eating more of?” While vegetables, fruits, dairy and whole grains would all be perfectly suitable answers to that question, my go-to response is fermented foods.

Fermented foods have been around for thousands of years. Fermentation is the process of using specific microbes – for example, bacteria, yeast, and molds – to transform one food into another. For example, the fermentation process transforms milk into yogurt. Fermented foods are unique because they can contain live microbes, which can confer health benefits beyond simple nutrition. For instance, did you know that the microbes in fermented foods can help inhibit pathogen growth in the gut? Or, that eating certain fermented foods, such as yogurt, is associated with reduced chronic disease risk?

Government organizations across the globe provide dietary recommendations to help guide people choose the type of foods or diets that promote health. Commonalities include eating more fruits, vegetables, whole grains, beans, legumes and dairy. Another commonality – albeit a disconcerting one – is the lack of a recommendation for consuming fermented foods even though fermented foods, including red wine, kimchi, soya, and yogurt are key parts of healthy diet patterns.

Several recent publications have discussed the need to encourage the consumption of foods that can directly and beneficially impact our gut microbiota to improve overall health (e.g., Bell et al. or Gordon et al.). Identifying and consuming foods that can selectively impact the microbiota to benefit the host health should be a priority.

The time is now. Health professionals should review available evidence to determine how fermented foods fit into dietary recommendations to promote a healthy microbiota. They should encourage the public to increase their consumption of fermented foods to support the health of their microbiota and body. That way, the next time any of us are asked “What should I be eating” we can point to dietary recommendations and say — Fermented Foods!

Read more on fermented foods here and here.