Episode 91: You Are What You Eat: Examining Beef and Plants With Dr. Stephan van Vliet

Hi, friends, this is John. Welcome back to the Regenerative Agriculture podcast where we talk about agronomic science and cultural management practices and all the fun things that are related to regenerating our soils, our lands, our stewardship, the economic opportunities on farms. Today we have a conversation I've really been looking forward to for a while. And if you haven't encountered Stefan Van Vliet's work yet, then I really encourage you to look it up and to dig into some of the things that he's been doing. Stephan, I'm really excited to have you here today and for you to share more about the things you've been working on and your trajectory over the last decade or plus, tell us a little bit about what you are studying, what's been the scope of your research and when did you first start studying these topics more intensely and what were your early questions that you were trying to get answers for?

So it started in 2019. Yeah, is when we started on this. And it kind of started interesting. I once got a call from two colleagues, Fred Provenza being one of them, and then Scott Kromberg at the USDA being another one. And they are ecologists, animal scientists. And they gave me a call and said, stefan, we heard you speak somewhere and we're looking for a human nutrition scientist to collaborate with. We spend our careers looking at livestock grazing and how different forage and feed selection impacts animal health. But we've never really made the bridge towards human nutrition. And I was already interested in wanting to study grass fed beef and it actually worked out. So it's kind of random that it worked out, but I was like, yeah, let's, let's do it. And then the first year we tried to find funding and of course after many unsuccessful attempts, it became successful. And so the early work, what we did was we were just more looking at this in depth case studies. When I was in Duke University, we worked with three farms in the South. They were using rotational grazing practices. So we went there over the summer multiple times, collected pasture samples, soil samples, collected meat samples at the end, and were also able to obtain meat and samples from a few feedlots and made initial comparisons and found indeed that there are differences and that those differences go quite a bit beyond just omega 3 fatty acids, which is what you typically hear from people, that it's like, okay, grass fed beef has a benefit for omega 3 fatty acids, but not really beyond that. But what we were finding is that if you use what we call a metabolomics approach, so it's really Deep metabolic profiling of the food source, looking at hundreds of compounds, you actually see that there's quite a large number of differences based on what, what the animal ate. And what we've been studying a lot is phytochemicals, which are plant secondary compounds, so they're transferred from the forages into the meat. And these are things such as terpenes, polyphenols, tannins, flavonoids, etc. And we see that those are typically known more with the laban as antioxidants. They have all kinds of potential effects. If we throw many of these compounds in the laboratory on a cancer cell line, it may reduce the cancer proliferation. Not saying that grass fed beef reduces your risk for cancer, that's, that's not what I'm implying. But my point is, is that these compounds, they get transferred from the animal. And it's kind of like if you think about it as a human, right. If I were to ask you, John, if I put you on a Mediterranean diet for three months or standard American diet for three months, you would say, well, of course, I expect large differences at the end. Well, if we put animals on a total mixed ration for four months, or finish them out on pasture for four months, completely different diets, then all of a sudden we don't expect differences. And I must admit it's easy to say now after the fact, because I was also not expecting these differences to this extent. I mean, there was some older research from the French and Italian scientists, particularly in cheese, that were looking at what if we graze these animals through alpine landscapes or in Sardinia, and they were doing this for flavor. But then if you look at those compounds, chlorogenic acid, Gallic acid, cinnamon acid, as a human nutrition scientist, I'm thinking about this, looking at this, yes, these are flavor compounds, but these are also compounds that have potential health effects. And it's that combination between flavor and health. So that is what we were studying largely and kind of took that work and started doing that in North American systems particularly. What we've studied now is bison and beef as well as milk.

My goodness, Stephane, your responses elicit about half a dozen more questions. And I'm not sure which pathway to go down, but why don't we start with the easy one? Is what have you been learning about beef and bison and milk? Like, how significant is the variation and what have you learned so far?

So if we look at term nutrient density, and typically it's how I at least define it, and others too, is the amount of beneficial nutrients per unit product. So it could be 4 ounces of beef. And if it has more nutrient density, it probably has more B vitamins, fat soluble vitamins, phytochemicals, more omega 3s which are potentially beneficial nutrients. So what we've been finding is, is that there's quite a large variation in nutrient density. If we sort of look at grass fed and grain fat as homogenous groups, which they are not. There's grass fed, isn't grass fed, isn't grass fed, grain fed, isn't grain fed. But for e sakes, we see about a 40% difference in the abundance of many of these nutrients. So sometimes higher, sometimes lower.

Is that a 40% variability within each of those two groups or between the two groups?

Between the two groups within each groups, especially grass fed, it's a little bit of a wild west. We found an 11 fold variation between samples. So the lowest grass fed and the highest grass fed were 11 fold difference if in, in many of the especially plant secondary metabolites.

And how much overlap is there between the lowest grass fed and the grain fed?

So the highest grain fat is probably twice as nutrient dense as the lowest grass fed, but the highest grass fed is still six, seven times more nutrient dense than the highest grain fat. If we consider these phytochemicals and omega 3 fatty acids particularly, you know, you.

Have a really interesting perspective approaching this from a human nutrition background. What are the implications of these higher levels of plant secondary metabolites coming through meat, coming through livestock products and being consumed by people? Like there's like on one level we intuitively understand that this must have some positive benefits for our own immune systems. But I'd love to just hear your perspective from a human nutrition point of view. Like what are some of the possible manifestations and how might this play out from a public health and a human nutrition view?

I have no idea, John. There haven't been any randomized controlled trials done yet, so we're running two in our lab at the moment. A very acute study where we're just comparing grass fed beef, grain fed beef and an impossible burger, and pulling blood from people for five hours afterwards to see.

I would only volunteer for one of those three categories.

Yeah, well, we don't tell you, so you, you wouldn't know, right? We're blind, blinded for it. And. But yes, so am I, so are we. But I, when I walk through the hall and into one of those, one of the exam rooms, I can definitely smell whether it's an impossible burger or beef. I don't think I can pick up the smell difference between grass fed and grain fed. But if I, you know, say hi to the participants and check up on them, then yeah, I know immediately if they got an impossible burger or not because it has a very distinct smell, especially in the morning, because they consume it first thing in the morning on an empty stomach and then stay in our lap. So that's the initial thing. We're just really interested. You know, we see difference in composition. Obviously the difference in composition between beef and an impossible burger is much larger than grass fed and grain fed beef. Because you're comparing a plant and an animal there we found a 90% difference in metabolite abundance. But yeah, for now it's just trying to understand does your blood look different because you can actually see things in the blood already that are coming from the food source. Early on in my career we did a lot of amino acid tracer studies. So we would have a labeled amino acid that was actually incorporated into an egg or meat by feeding the animal that's labeled tracer. So it's a stable isotope tracer that kind of has a flag on the amino acid. And then you, if you eat that egg, then you see it appear in your blood after about 15 minutes already. So you, you are what you eat. There's a truth to that saying is your blood starts to somewhat reflect what you just ate. And so that's initial study and then we're doing a longer term trial as well. Actually two longer term trial. One is though we're not per se isolating the effects of beef in that one or animal sourced foods, but we're comparing a regenerative diet which, which is mean all foods are sourced from regenerative agriculture and all foods are sourced from conventional agriculture and people consume those diets for seven weeks each with blood, urine and stool collections pre and post. And we give them their entire diet. So the meat is more from, from conventional systems, CAFOs or grain fat. But also the produce is either coming just, you know, your regular non organic store bought produce or coming from integrated systems. So that's one. But then also we're looking at beef, pork, chicken and eggs specifically as well in a separate study. So we have multiple randomized controlled trials going on that we're trying to hope, at least hope to find out. Like, okay, does this have an appreciable effect on human health or do we see anything changing in their, in people's blood? Especially with randomized controlled trials, you're measuring more biomarkers. You cannot say anything about long term. Well you can make an assessment on it, but obviously no one's going to develop heart disease in a, in a seven week study. And if they do, then I probably have some explaining to do to the irb. So, so that's, that's not the, not the case. But you know, you see inflammatory markers or cardiovascular risk markers change. So long story short is that we don't know the answer. We'll have to perform randomized controlled trials. But yeah, this is really came out of the fact that when we started to profile beef and bison that we started saw differences that went quite a bit beyond just omega 3 fatty acids. So on paper I would say yes, grass fed beef or grass fed bison looks healthier. Whether this translates to a beneficial effects on human health, not sure. What we do know though is the following, that if you eat grass fed beef or pasture raised animal source foods, you see the blood omega 3 profile of consumers go up. If you eat grain fed beef in a randomized controlled trial, it typically stays at the level where it's at and that's been known for about 20 years.

So let's go back to the studies that you've been conducting on beef and bison and milk. You've described the remarkable variation in variability that you've observed and so these health markers within the livestock. I think this certainly is valuable and important information for anyone who's producing livestock. But also considering the possible implications that there might be, or the probable implications, I would even say that we're likely to discover human health correlation once we figure out what it is that we're looking for. What contributes to the variation in phytonutrient density? What are the contributing factors that you've been able to identify that really contribute to producing really nutrient dense foods? And that also kind of begs the question, there's this constant conversation that keeps evolving of what defines nutrient density? What is nutrient density? So that's perhaps even a precursor question.

Yeah, I mean there's no set definition for nutrient density, but like I said, I, I consider it to be the amount of beneficial nutrients per unit product. So typically I think of it in, in 100 grams. That's how we express it and that's how it's expressed in the USDA nutrient reference database. So let's say if you have more alpha tocopherol and beta carotene, which are precursors to vitamin A and elsewhere as vitamin E, if those are twice as high per 100 gram beef, I'd say that is more nutrient dense. If the omega 3 are five times higher in grass fed beef versus grain fed beef, I'd say that's more nutrient dense. If the antioxidants are twice as high, I would say that's more nutrient dense. So that is kind of how we define it. But there's also, the interesting thing is that maybe you get less of the stuff you don't want as well. I mean, we've also been looking at things such as, you know, and this is this you really get at the intersection of are we looking at animal health, are we looking at human nutrition here? If we measure things like homocysteine, homocysteine or for H and E, which is a lipid peroxidation product, these are higher in grain fed animals, which is probably due to them having a little bit more oxidative stress. And those things when they are higher in our blood are associated with an increased risk of metabolic disease. Now we don't, again, don't know how that relates to us consuming that from, from beef. But these are also things that we are thinking of. But you know, lipid peroxidation, it happens within, within the animal. It's probably a marker of their status of metabolic health. But we also know it's a marker of our status of metabolic health. So then when we eat that, what is the impact on that? And yeah, those are some, indeed some of the remaining other questions that we have as well.

You mentioned a bit ago that we've known for 20 years that consuming grass fed beef can have an impact on the Omega 3 profiles in our blood. And I find this interesting because I've heard other nutritionists make the argument that grass fed beef is not a significant dietary source of omega 3 and that if we want to consume omega 3s, we need to be consuming salmon or something like that. What is your perspective?

Yeah, that's so popular. It's one of those things that someone starts to say it and then everyone starts to repeat it and then it becomes truth. And then if you actually look at the literature, there's probably 10 randomized control trials. Not just on beef, mind you. There's only been two on beef. There's another one on horse meat. We don't consume it in the US but elsewhere in the world to consume it. There's on pasture chicken, pork, I want to say. Yeah, a few other studies as well. I want to say yak meat I think is another one.

And I think across the spectrum, in other words.

Yeah, across the spectrum, Yeah. I mean it doesn't. If you eat Omega 3 enriched meats, then you See the blood profile. So I always find that quite interesting when people say that because there's some good evidence, probably you know, 8 to 12 randomized controlled trials that clearly have shown that. And this was already known in the 90s. Sinclair, which was an Australian scientist, first study this in the 90s and he was feeding people kangaroo, whitefish and grass fed beef and I think also grain fed beef. And he did notice that in the grass fed beef, the kangaroo and other passionate animal and the whitefish, they all went up. Of course if you compare grass fed beef to salmon, it's a significantly less in there. I mean if you look, if you combine the Ala, EPA, DHA and DPA, which are the four major omega 3 fatty acids in grass fed beef, if you consume maybe 100 grams, you might get anywhere from like 50 to 100 milligrams. If you consume salmon, it can be as much as, you know, one and a half grams or something. If you look at sockeye salmon, really high quality salmon. But if, then if you look at whitefish, it actually is a little bit closer to grass fed beef. And so the short end of it is, is that yes, it can represent a meaningful source. Is salmon higher? Yes. But if you look at what people more typically consume is we consume probably more, especially in western population, more meat, milk, eggs. So by just virtue of consuming that more often, you just, it contributes more without question.

Like it's. I don't have the stats, I don't know what the data is, but I would imagine we probably consume an order of magnitude more animal and poultry products than we do fish.

Yeah, that's probably a safe assessment, especially in our western population. And you know, that's not to say that we shouldn't consume more fish, I'd say, I mean it depends on what kind of fish. But if you have, you know, very efficient animals, mollusks for instance, you know, if we consume more things such as perhaps oysters or mussels and things like that. Right. These are incredibly nutrient dense foods. Talking about nutrient density, those typically have orders of magnitudes in, in terms of B vitamins and zinc and, and iron as well. But my point being here is, is that yeah, there's definitely been studies done, especially in Irish and Australian populations that would suggest that they can contribute meaningfully. And you can see a movement, a shift in the Omega 3 profiles. And like I said, I mean it's not nothing either. If you consume a hundred grams of beef a day and you end up with 80 milligrams of omega 3s, that's that's not nothing.

Yeah, certainly. And, well, it's obvious if you're producing a shift in the blood profile, then it would be reasonable to expect that that's eventually going to lead to health outcomes.

And one important thing also, John, is the following. And I think people underestimate that docosopantenoic acid is actually readily converted to eicosopantanoic acid, epa. It's conversion to DHA is not as high. But people oftentimes, when they talk about omega 3 fatty acids, only consider EPA and DHA, icosapentaenoic acid and docosahexanoic acid. But there's also DPA, docosalpentanoic acid, which is readily converted to EPA. And that's usually not taken into consideration. But it's actually the risk. One of the richest omega threes, together with alpha linolenic acid in beef. So. And that is readily converted in our body to epa. So that's also probably explains why people usually take into account, say, oh, it's only a few milligrams of DHA, maybe like 10, 15 milligrams of EPA. Yeah. But there's another maybe 20 milligrams of DPA in there that can get converted within our body.

Why is that usually not taken into consideration?

Because I think people heavily focus on EPA and dha. And yeah, I'm not sure, not sure why that is. But if you look at your fish oil pills, it only manages EPA and DHEA, but it doesn't mention DPA. So, yeah, I'm not 100% sure why that is.

All right, coming back to one of the questions that I asked you earlier that we then moved on past is do you have any insights at this point into what contributes to the density of these phytonutrients in meat and milk?

It's plant diversity and not overgrazing. I'd say those are having productive plants and having a variety of productive plants that seems to contribute most to it. So it's almost like the animal can select from what we consider the buffet or salad bar on pasture, can select from a wider variety of plants. And then also the importance is, is that those plants are grazed but not overgrazed. So what we typically see is that animals that are rotationally grazed, maybe, you know, 30, 50% of the plant remains stimulating new growth and they're moved around the landscape or the farm. And then also the diversity piece, if there is, you know, 20 plants, 30, 40 plants on the pasture, as opposed to one or two dominant species, more of a Monoculture, then you also see that. And it's. I often like to draw the parallels with human nutrition. It's kind of. We know that dietary diversity for humans is key too. Right. And if we went to a buffet and there was only two foods available, or there were 20 foods available, we would probably be better able to nourish ourselves. And a cow, if you look at it sort of on a molecular basis, it's just another mammal like us.

Yeah, I find it interesting that you didn't mention there's obviously the plant diversity piece, which is not a surprise at all. But what is the contribution of the relative degree of plant health within that plant population? And I'm of course approaching this from the perspective of working with lots of produce and fruit and vegetable crops and nut crops, where I believe that. Well, I don't just believe we have some evidence that we can really significantly influence the phytonutrient content of plants based on plants microbiome integrity and nutritional integrity. So how does that piece contribute to the overarching view?

Yeah, no, it's a good point. We have to drill deeper into that to find that out as we are learning more and understanding these linkages is between even soil health and plant health and animal health and nutrient density. But yeah, it is a good point. I mean, if you are able to produce more nutrient dense plants on your pasture by virtue of, you know, your grazing practices or other practices that you. That you have, even if it's like, you know, planting cover crops or things like that, then yes, I see that could have a synergistic and beneficial effect. But we don't have evidence for that at the moment.

More homework required. You know, this is one particular domain of research where that phrase is just a constant refrain, isn't it?

Yeah, I could probably work on this for the next 40 years and definitely still don't have all the answers.

You know, different plants produce very different types of metabolic compounds. And I recall in the interview that I had with Chris Nichols, this is now a couple of years ago, she was describing how they were identifying, if I recall the conversation correctly, they were identifying this specific compound that was produced by soil biology and channeled through mycorrhizal fungi into plants and then from plants into meat. And they were actually measuring this compound in beef and I don't remember what the compound was exactly.

It's ergothioneine.

Oh, you're familiar with that?

Yeah, yeah, it's ergothioneine.

How many other stories are there like that?

We have a similar Story. Yeah, I mean, we're finding the same thing. Yeah. Ergothioneine is only expressed in a few soil fungi and cyanobacteria within the rhizosphere. So it has to come from the soil and it makes its way up through the food web. And it has been found at least in animal models. These are talking about rodents or laboratory models. So if we throw it in a petri dish that it has antioxidants and anti inflammatory effects. There has been more interest now also in human clinical trials to study whether it has an effect. But yeah, what you see is, is that more biologically active soils can measure this, for instance, through total exchange capacity soil organic matter. You see that there's more ergothioneine in the, in the plants as opposed to total mix ration. That's the comparisons that we have done. So more ergothioneine in pasture versus the total mixed ration and then also more ergothioneine in grass fed beef than grain fed beef. And we're now exploring correlations between soil health because we're building a big enough data set with hundreds of farms. Can we see a correlation between soil health, markers of soil health and the amount of ergothioneine in the meat? And is that positively correlated? And those are things we're now exploring. Indeed. So ergothioneine and then hercinine, which is a metabolite of ergothioneine, are two main compounds that we've been studying and indeed are very well picking up in, in meat. And then the next part would be, can we pick that up in the human as well? There have been studies with mushrooms. Mushrooms are very rich in herbathionine because there are fungi, right?

Yeah.

And there's been studies done with that. And yeah, if you eat, people that eat more mushrooms have higher amounts of ergothioneine in their, in their blood.

Interesting. So it's fascinating. Have you, do you have any early insights into any possible correlations between soil health and transferring through into meat and ergothioneine levels? Or is that. You don't have that data yet?

No, we don't have that data. Not, not big enough at least. No, not that we can actually, you know, we've seen that correlation or that relationship, I should say, in our initial studies. What we've basically seen, John, is that when we were doing very in depth profiling on, on, on several farms, and these were five farms, what we did was we took soil samples of the pasture. We actually took the plants from the Pasture. Then we asked the farmer, show us the most conventionally managed cornfield that is closest to you. And usually it was the neighbor or, you know, another neighbor a mile apart. And we collected soil there. And then also when we were there at the end of sort of the growing season, we collected some corn and tested that. That was a model of what goes into a feedlot, if you manage to grow feed crops, right? Because, I mean, about 20, 30% of that corn is likely to go into, into the feedlot. Also in other uses, of course, biofuel. But. And what we found there is that sort of organic matter was reduced, the exchange capacity was reduced in those corn fields that were in the same ecoregion, Mind you, it was only a mile apart. So this is definitely a management effect. Pasture was higher, so organic matter, higher mineral content. And then also we saw more thyronine in the pasture samples as opposed to the corn samples, and then more thyroidine in the meat. So we did see this, this relationship, but only if you have. And there we saw a moderately positive correlation. But mind you, this was five farms. So I feel a lot more comfortable by making this statement if we had seen this replicated in a larger number of farms to see if there's actually that that relationship holds up in a broader data set.

When I think about the contribution of soil fungi and being able to track that throughout the food web, the next question that comes to mind is whether we might also be able to track the contribution of specific plants. The one example that comes to mind is a group of organic poultry producers that I worked with a number of years ago who were persuaded that within their own families and their own personal health, they were observing a positive health responses based on feeding poultry garlic powder. And so they were getting garlic powder, they were getting much better feed conversion. They were getting overall improved health in the poultry that they were convinced anecdotally was also having a positive health impact on humans. And so you mentioned, when I asked about what are the factors that contribute to this phytonutrient density, your answer was plant diversity and not overgrazing. And I guess within that, are there specific groups of plants or specific types of plants or even, perhaps even species that you've been able to identify as having observable impacts?

Yeah, we've definitely noticed some things seeing relationships in our data is that especially some of the plants you mentioned. It's interesting that you mentioned poultry because there's a large body of literature that looks at feeding poultry, indeed, things like onion powder, garlic powder, rosemary, sage, and what you typically see is that bird health improves. It kind of has a natural antimicrobial or antibiotic. And then also it enriches the total antioxidant composition of meat. But what we are also seeing indeed is that, you know, when animals are grazing things like wild onions or something. Yeah. There you see onion derived compounds such as chlorogenic acid or quercetin, gallic acid, which would also be actually in garlic. Yeah, you see that being enriched in the meat and maybe 10 times higher than the next sample that did not have those plants on, on its pasture. So it is actually those little nibbles on those colorful flowering plants that sometimes people even consider as weeds because it's not grass that is actually having a beneficial effect. It's almost like the equivalent in humans would be to put some spices on our food. Right. And that's kind of the same thing with the animal. And we think like, oh, having a few, I think a bulb of garlic in our pot roast. How much difference can the garlic make? Well, it does actually provide beneficial effects. So it's the same with the animal with the nibbles on these, you know, wild onion plants or maybe a little bit of like the flowering clover and other things that is chock full in these secondary metabolites. So oftentimes when we see a pasture and then, you know, we see some colorful plants on there as well, in addition to more of like the grasses. And this is especially in rangelands. Right. Is there's probably 150 plants on the rangeland, especially in mountain pastures, and sort of herding these animals through it. Yeah, they're probably being exposed to 150, 200 different plants. And that's where you see this diversity. So that's why I'm coming back to the diversity piece. But yeah, you're right. Different plant species provide different compounds because we also see with more legumes, we see more isoflavonoids being accumulated in the meat. So there's also this ecoregion effect where you can see, oh, this person is grazing some legumes and you see compounds, isoflavonoids are rich in legumes. And you see those then appear things like for mononithin or other isoflavonoids, you see those accumulating in those samples, but then not in other samples because they weren't really grazing any leguminous species. So, yeah, there is definitely that effect, again, analogous to what you see in a human.

What this brings to mind for me is what if we. And this is perhaps less relevant for Rangeland, although it's certainly management associated, but where grazing land is actually being planted, where seeds are being planted, and there's this active engagement with trying to improve and regenerate the landscapes. Perhaps we need to rethink our species selections not just in terms of providing forages, but also, you know, what if we started thinking about each of these plants in the context of herbal medicine. If you look at the herbal medicinal history and the knowledge that has been accumulated, practically all plant species are known to have some very specific medicinal value and benefits, particularly when in concentrated form. And my thoughts naturally kind of just jump to some of these plant species that are known to be anthelmintics, anti parasitic plants that can be grazed on for sheep. Well, there's quite a nice body of research on the use of sainfoin and chicory and trefoil as an enthalmintic that when you graze livestock on these plants, they have this anti parasite effect. And so it would be really interesting to understand when livestock are nibbling on these plants as culinary spices, as you described it, that obviously is benefiting their own health. And do those benefits transfer? Well, there's two questions. One is do those compounds accumulate in the meat? And then of course it's speculation to think about whether those benefits might transfer to people. That homework still needs to be done.

Yeah, they definitely transfer into the meat. You can clearly see that. And it is interesting, John, if you pick up any book before the 70s on, you know, traditional medicine or traditional plants in western rangelands, for instance, you know, it's usually older books because it was prior to the advent of when we started to use more synthetic compounds. Right. Which actually many of them are derived from sort of natural origin. But yes, this is well known, especially on, on in traditional populations or even earlier sheep herders. Right. Is like selecting certain plans or, or hurting the animals through the landscape to pick up certain plants because they have no medicinal effects on the animal. Indeed, now we are quick to give them a round of antibiotic treatment, but back in the day when that maybe wasn't available or cost prohibitive. Yeah. You would find other ways as a producer to make sure your animals don't get parasites. Right. And that was through grazing these medicinal plants. And yeah, there's a whole body of knowledge on it and especially in some of these older books. Yeah, it's fascinating to read indeed that. And I often think we've kind of lost that, that knowledge a little bit as we moved away from. From wisdom and more into like show me the evidence. Right. And so there's, there's a danger of, of thinking that if, if we can't prove it in a study that it doesn't exist. And I, I sometimes think that's sort of now 20, 23, that is sometimes the state that we're in. Right. This is something I often struggle with as well when I visit farmers is we're on the pastures or these rangelands and you can just see it's steaming with life, biodiversity. Right. And you cannot help but think to yourself like, hey, I don't think we're destroying the earth here, but if I go back to my office and read a whole slew of scientific papers, I could convince myself that that pasture raised, that grass fed beef operation that I just been to, that is steaming with wildlife, birds, insects is the absolute worst thing for the environment because of its methane emissions. Right? Yeah, that's sometimes what we're, what we're up against. And in sort of when we take these complex issues, simplify them according to a few different metrics and then make policy based on that. And yeah, I mean I often, you know, ecology, it's not my, my primary expertise, but I often talk about this with other scientists and thinking like, and even farmers that are observing this day in and day out, you would call that wisdom. But it's super hard to prove that scientifically.

One of the reasons it's so difficult to prove scientifically is that science really struggles once you include multiple factors and complexity. It's that the scientific method has almost become associated by definition with single factor analysis.

Yeah, the reductionism in science, I mean, we have to apply a little bit on reductionism. Right. And to kind of simplify things, to understand things. But yet there's this inherent risk in that, that we simplify this complex issue, reduce it to a single factor and then it's no longer representative of that complex system. And I think that is indeed something that is oftentimes happening. And there's a lot of research being done now to try to understand that. But yeah, it is, it is, it is super hard to indeed to categorize that. And therefore I think there's sometimes this little bit of like head butting between sort of the, the ground roots movement, the farmers and sort of the academic sphere where farmers are saying, well I, you know, 10 years ago when I moved onto this land, I've seen it being regenerated, I've seen bird species return, I've seen wildlife return, insects return. But then you have to categorize that scientifically. It's very hard and then if you go to the average meta analysis, it would say that, well, typically with grazing biodiversity reduces. But yes, if we over graze or continuously graze in nine out of 10 instances, then 90% of your findings are going to be that it had negative effects. I'm interested. What are the other 10% doing?

Right, exactly, exactly. Stefan, we've had a fascinating conversation about all these various topics related to nutrient density. But you know, people tend to remember stories. What are some of the stories that are remarkable experiences that you've had that really stand out in your memory?

One particularly, and it's almost been a yearly field trip now as we go up to Idaho in the Salmon Challis National Forest and there's a farmer there by the name of Glenn Alzinga and he runs all the spring ranch. Yeah. And it's such a fascinating story because what he does and his crew does, they graze the animals on horseback throughout the grazing season through these fast mountainous landscapes. And I don't know if you've ever seen a cow climb a mountain, but they can be quite Atlantic if they want to be. So and we always visit, it's an hour deep into the mountains and it is so fascinating because what he typically does, he grazes a piece of land every few years, three or four years, for only a few minutes. So it's very high impact. And then, and then move on. And even when you're talking to him four or five minutes and then all of a sudden you turn around, you're like, where the hell the cattle go? And they have been moved around again and so they're continuously moving. And what is particularly interesting about those rangelands, it's so incredibly diverse. Only 200 plants that they get exposed to. And when we then take that into the lab, we have seen compounds in meat that I was like, no idea that this would be in here. And these are some of those, you know, wild onion derived or other flowering plant derived compounds that we have not picked up before, but we pick it up in that meat. And also it's interesting is that we measure also fatty acids. And this was the only sample that I've seen an omega 6 to 3 ratio that was below 1. So more omega 3 than omega 6s typically like sort of the holy grail is 1 to 1. Not a lot of grass fed farmers reach it. But I'd say anywhere between 1 to 1 and 2 to 1 is an excellent omega 6 to 3 profile for that one. That actually dipped below 1 for a few of those samples. And yeah, that's such a fascinating story and must have been one of the best pieces of meat that I've ever had. And another fascinating story that just pops to mind was we were testing some, some chicken samples from actually an Amish farmer, Miller's Bio Organic Farm.

Yeah. In, in Pennsylvania. Yep.

Yeah, Pennsylvania. And we were just, I mean I bought them just off, you know, from their website and, and I had those in the past and I thought that was delicious chicken, the best chicken I've ever had. And we tested those in the lab and they also had an omega 63 profile of one. And I did not know that was possible in chicken because there is absolutely no reference to that in the literature. Most bastard poultry have an omega 6 to 3 ratio of 7 to 1 because they're being fed quite a lot of grains. But these animals an omega 6 to 3 ratio of 1 which is unheard of in, in poultry. So that was something that really stood by me is the fact that yeah, it is possible.

It's really interesting. I wonder how they are they accomplishing that. Perhaps by feeding linseed or flax or are they just not feeding much grain?

Yeah, they are feeding flax indeed, kelp, even some fish meal. And then they're feeding peas, wheat, barley, so no corn and soy, which is typically high in omega sixes also. Yeah, that, that's mainly it's, it's kelp, flax and then some fish meal. And it also doesn't have a fishy flavor so they must feed that alone amounts. But we know flax is one of the richest sources in omega 3s, so. And you can see that because especially alpha linoleic acid, which is the precursor to the omega 3 fatty acids that we derive a lot of benefits from. ALA in itself as benefits as well. But with elongation you get DHA and epa, but especially the ALA is very rich and we know that's very rich in flax, so they're clearly accumulating that. And. But I was also just surprised that yeah, the meat is just so moist. I'm usually not a huge chicken consumer just because I always consider it a little bland and you need to brine it and spice it really well to get like, you know, a nice piece of meat. But those thighs were amazing. And I used to buy those when I lived in North Carolina because there was a drop off location actually in the Raleigh Durham area. And I just vividly remember those chicken samples and we had a chicken project and I was like, well, what if I just slip those in to see what they Were like, because that's the best chicken I've ever had. And yeah, the nutrient density piece sort of became super apparent there. Again with a mono grass trick. They're probably even. You know, it's even more apparent is what we're seeing because you know, grass fed beef and grain fed beef and omega 6 to 3 ratio of about 2 to 1. One to one in grass fed beef. In grain fed beef it's about 8 to 1. But then if you look at sort of your conventional CAFO poultry that is eating a standard corn and soy feed indoors, they maybe have an omega6.3 ratio of 18 to 1, 20 to 1. So if you then also produce chicken with a 1 to 1 ratio. Yeah. Then the difference is huge.

Obviously when we think about these different omega 3 to 6 ratios. You mentioned a key phrase earlier of or one that I think is key. With my limited understanding of that of antioxidants versus markers of oxidative stress, I'm sure I have an overly simplistic view that might be inaccurate. And so I'm going to ask for your insights here. I've generally tended to think of this nutrient density conversation, the impact that it has on human health and potentially on animal health, just very, very broadly as compounds that have an antioxidant effect versus those that have an oxidizing effect or those that are anti nutrients that can inhibit digestion or have inhibitory effects of some type. Is that such a simplistic way of looking at it as to be inaccurate and what is a better way to think about it?

Yeah, it is unfortunately a little bit more gray John, because we think of things. Yeah, no, I hate to break it but you know, phytic acid, right, gets a bad rep on social media in particular phytic acid, because you know, it's rich in beans and being being a digestive inhibitor and it binds minerals particularly so making for instance the zinc and legumes less bioavailable. But phytic acid also has an antioxidant effect to our tissues. So maybe some phytic acid is good too much. You might have some digestive issues. Other examples are. But mind you, this is more supplementary form. But there's a series of classic studies on beta carotene, on carotenoids and also vitamin C. They're antioxidants, but when taken in high supplemental doses become pro oxidants. So it is not that black and white. But the good news is is that at least from getting these from food sources and it is probably because they come in a complex food matrix with A bunch of other compounds like beta carotene, while it being the major carotenoids, it comes probably with 30 other carotenoids in. In foods. So there are co factors available that probably prohibit maybe some of these issues. So eating an orange and getting vitamin C from oranges. The orange does not act as a pro oxidant. Taking a vitamin C supplement. Yes. Can become a pro oxidant. Eating carrots and getting beta carotene through carrots or sweet potatoes. No indication that it can act as a pro oxidant in normal dietary amounts. Take a beta carotene supplement. Yes. It become. Can become a pro oxidant. So there is. Yeah, there is. There's a gray area that. And even this with livestock grazing, we know that some alkaloids can have actually beneficial effects. But if an animal starts to graze too much clover. Right. We know they get reproductive issues. So. And usually that happens because the animal doesn't have enough other things to select. So it's. If there's a bunch of clover, then. Yeah, I mean, you know, if the option is not sexually reproducing or starving, then you're probably going to pick the not sexually reproducing over starving. Right. And I know putting. It's very crude here, but so that is also. Also the key. But we do see that, you know, grazing some clover on the pasture. Yeah. I mean, can have some beneficial alcohols that. That can incorporate into the meat. So it's definitely a dose response thing.

Yeah. It reminds me also of the coumarin, I think, is originally derived from sweet clover and was originally called sweet clover disease, I think, or something like that. Or had the effect of causing blood thinning to the point of death for livestock that were grazed on exclusively sweet clover.

Yeah, correct.

Fascinating history around how coumarin was discovered. Yeah. And then, you know, Stefan, there's this classical argument that gets refreshed by journalists who don't have anything better to do every four or five years about organic is not more nutrient dense. And I'd like to do a figurative facepalm and say, well, the definition of organics has nothing to do with nutrient density. It's the absence of toxicity, not the, not the inclusion of nutrient density. And my. Just experientially looking at the farms that we have the privilege of working with and observing many different farms in the landscape, there is a certain percentage of organic farms, let's just say broadly, 20%, who are holding true to the foundational values of the original organic pioneers. They are seeking to build soil organic matter and they are using compost and they're using computer crops and they're trying to regenerate their soils and build diversity into their ecosystems. And these 20% of organic farms are producing some of the most flavorful, aromatic, most attractive fresh fruits and vegetables that are out there. And then you have the remaining 80% of organic producers which either are earlier on that pathway or don't have a particular interest in that pathway, that, speaking crudely, appear to be producing absolute junk. And so in my mind, there's no association between organic certification and nutritional integrity because it is not a part of the organic certification process. And I'd love to get your see if you have any insights or thoughts or perspectives on this recurring debate. That is a pointless, improper framing as far as I'm concerned.

Yeah, no, I agree. And the interesting part about this, if you look at a series of meta analysis, on average organic is more nutrient dense than conventional. So I don't know where this comes from. It comes, I think it's the same thing as that myth that grass fed beef does not impact omega 3s. And someone starts to say that and then people start to repeat it and it becomes truth. But if you go into the literature, read a large number of meta analysis, they typically favor organic a little bit in terms of nutrient density.

It's called being selective about the data you choose.

Yeah. Or not looking at the data at all. So I've never quite understood that because there are a number of good meta analysis over the last few years that have been done over the last 10 years and you know, done in a large number of produce. And yeah, if anything there's a neutral effect or it shifts slightly towards the organic. That's typically what you see. But I agree that organic is not always more nutrient dense. So if, if journalists say that, then yes, that is a true statement. Yeah. And I think it indeed comes back to the fact that, you know, if you have an organically managed monoculture, you're probably not going to be very nutrient dense. Whereas organic probably originally was polycultures, putting synergistic crops, growing them next to each other, so that there is a sort of health that's being built. Right. And yeah, I was in South Dakota the other day at one of the Turner Ranches and we drove past one of the largest organic crop farms. And yeah, it was a lot of it, it didn't look great. I mean it was, you know, a lot of bare soil, a lot of monoculture cropping. And. But if you go to other organic farms and There's a bunch of different crops integrated. Then obviously that organic farm is probably going to produce more nutrient dense foods than, than. As opposed to your monoculture. So. Yeah, 100 agree. And you know, regenerative will, you know, it's in the early stages, will that also have incredible variation? Yeah, no doubt there will be a variation. And it, I think it comes back to large part also management practices.

Without question. You know, each one of us as we go through life, we are, we are shaped by our perspectives, are shaped by the experiences that we have and the, the things that we've learned and the things that we've chosen to ignore. So we all have our own unique points of view. And I'd like to ask you, from your point of view, what is something that you believe to be true about agriculture that is perhaps different from the mainstream view? What is your unique point of view that other people may not be aware of?

Good question, John. One of the things that immediately popped to mind, but that's because we just talked about it, it is that the viewpoint that I read all the time, that there's no nutritional differences between pasture finished animal foods and conventionally finished animal source foods. And that is, I think, different from the mainstream view. And you know, if you just think about it, like I said, we had the comparison earlier. If I put you on a standard American diet for three months or four months, or put you on a whole foods diet, and I'd ask you, John, do you think my health is going to be different, differentially impacted? You'd be, yeah, of course it is. But then it doesn't go for animals. Right. And we've kind of disconnected from that so much that we think we can feed or raise animals in very different ways and that has little impact on the nutritional composition. And that's something I read all the time online and even sometimes with fellow colleagues. And yeah, how unlikely is that? If, let's say if we go into the lab, take another mammal, we put rodents, lab mice on diet A or diet B for a couple of weeks, then everyone doing that research would think, oh yeah, of course, going to be major differences based on the diet. If we do a randomized controlled trial, people will be like, oh yeah, of course, going to be difference. If we do this systematically in livestock, which was what we're doing, then all of a sudden now there's no difference. And I think that is such a key point that comes to my mind. It's like, how unlikely is that because we're all mammals, that lab mouse is a mammal we are a mammal, the cow is a mammal. If you sort of distill it down to if I study a piece of meat or a piece of my own muscle or a piece of that muscle from that rodent, metabolically it is not that different. Here we have mitochondria, we have glycolytic enzymes, we have amino acids, we have the secondary metabolites, we have vitamins in there. It's not that different. So I think the key point is sort of, you know, what we do to our livestock, we do to our, ourselves. Perhaps, probably.

You didn't say that, but I will.

Perhaps. Yes, perhaps. Well, I have a colleague, Pablo Gregorini, who is, he's from, he's a scientist from New Zealand and he always says it like this and he says, and then we eat that meat, right?

Yeah.

And that's the power. And what does that then do to us? And yeah, this is a question that we have at the moment. But yeah, it is something to, to, to, to look into. Because yeah, you do see, you know, I don't want to make the claim here that animals in feedlots have metabolic disease. We don't know that. We don't even know what constitutes true metabolic disease in an animal. But what I can tell you this is that their metabolic profile starts to shift to one that you would see in humans that is associated with some metabolic derangements. The mitochondria intermediate enzymes are reduced. We see some dysregulation in glucose, glucose metabolism, we see these lipid peroxidation products increase, we see oxidative stress markers being increased. Right. I don't know if that truly means that, that they are diseased, but they definitely have. As compared to an animal that was raised very well, they don't look a little bit unhealthier, that is no doubt about it. And it doesn't mean that therefore grain fed beef is unhealthy to consume. And I honestly, if you ask me, I don't even per se think that is, that is the case, to be honest with you. If I think about this as the broader perspective of a standard American diet, right. If you're eating grain fed beef with a bunch of fruits and vegetables, then you know, I think you're pretty healthy to analogous to that. If a fast food chain starts to switch out grain fed beef with grass fed beef, that Happy Meal is not going to all of a sudden turn into a healthy meal, right? So when we go into these nuances of single food sources, we do have to take a step back and look at this, at the broader perspective of overall diet, which is really what's going to impact our health. And not so much eating an ounce of almonds a day to extend your life with five years.

Thank you. That was an awesome monologue. What is a topic that we haven't yet spoken about that is important for us to communicate or important for you to communicate?

Communicate to farmers, I'd say don't get caught up in the details as much. Do what works best for you on your farm. There's no magic recipe because sometimes I get the questions like, oh, what kind of species should we use? And I'm thinking, well, the species that were best in your landscape, right? That is so key. It's, it's sort of this local or contextual part that is, that is so key. What works in North Dakota might not work in North Carolina. So it is really looking at these, these local solutions. And even then sometimes this is sort of a bigger thought that I have is that, you know, I sometimes visit farms in southern Utah, northern Arizona and maybe raising a Black Angus cow in the desert is not the best idea because you know, these are animals that were come out of sort of, you know, and obviously there's interbreeding and then you know, maybe you, you breed in some different genetics. But in practice these are animals that are out of sort of wetlands, right? Green luscious pastures. And then you got to create that pasture in the desert by a bunch of irrigation. Oftentimes you see it in these mountain pastures too. There's leafy spurge or other quote unquote weeds. And I'm thinking to myself, well, a goat or sheep would not consider this wheat. They would consider this a yummy meal. And these weeds are probably chock full of secondary metabolites, antioxidants. So it is really also looking at that. And I know it's, it's especially here in the western part, this background of the sheep industry is really interesting, right? It was sort of like this, this idea, if you read about it and the guy escapes me now, but a researcher in University of Montana wrote about this. I think Anderson is his last name in the 90s of how the sort of the sheep industry disappeared because it was not considered cool to raise sheep, right? Real men raise cattle, sort of, that's this idea, right? Real cowboys raise cattle and it's not cool to be a goat boy or something like that. But in fact in these lands it probably makes a lot of sense to maybe have multi species grazing. So this is another part. And now we're getting a little bit out of the box because we have monocultures of cattle, pig and poultry mainly. But in natural ecosystems there's always a multitude of herbivores. So and if you look at studies on multi species grazing, the vast majority always find co benefits, synergistic benefits as opposed to if you grace and these studies have done a lot of them in the 90s and the 80s, graze cattle and sheep separately or you mingle them together, they're actually sort of a synergy that, that occurs. That's probably because there's differences in grazing practices and it does seem to benefit the plant as well. Because the problem is some plants don't get nibbled on, others do and you start to get a sort of more of a monoculture. And so the multi species grazing part is, is another part. And to even put it further out there, you know, there's often this discussion can the land sustain exclusively grass fed beef? And perhaps not is what some studies would suggest. But I think we should diversify our intake to a larger amount of herbal herbivores, duck, geese, rabbits, super efficient herbivores that can do very well on pasture and don't indeed a lot of, lot of feed. Having those integrated. I know this requires a shift or any more goat or eating more sheep. Right, requires a shift. But I think this idea, we think monocultures are a problem in plant agriculture. I think it's a problem as well in animal agriculture. We kind of made our pastures into a giant cattle farm.

That's a fascinating perspective and one that I can see very clearly because we know that these different herbivorous species interact with different plant species differently. And you know, one of the obvious variables that occurs, and I've experienced this, is you have some plants that rapidly become unpollatable if they remain ungrazed, if they become too mature, they become unpalatable to beef, for example. But at those unpalatable for beef stages, they are still palatable and used as a food source by sheep or goats. And so when you combine them, then you have these herbivores consuming these unpalatable species. Well, what happens the next time you go through grazing? Let's say it's three months later or six months or a year or several years later, all of a sudden those species that were previously unpalatable are now palatable to beef because they have already been grazed up upon by the other species and they're now in a vegetative growth stage. And so you have this, this interactive synergistic benefit where the diversity of species of herbivores leads to consuming. It changes the behavior of the herbivores as well and it changes the expression of the plants, both of those and tend to have a synergistic effect. So yeah, it's, that's a very valuable point. Thank you for sharing that.

Yeah. And of course it's easy for me to say here because you know, I can when I talk about this thing, farmers, of course, I mean, we work with several that do have multi species grazing. But yeah, it does consider a little bit of an overhaul of your business. Right. All of a sudden now you have to manage a herd of naughty behaving goat kids that do not listen. Right. So it's definitely not that easy and it requires probably additional perspective. But yeah, if you look at it from sort of the agroecological perspective or the ecology perspective, I don't think there's, there's no good reason not to do it. The reasons not to do it is practical or economical or, you know, you have to have the crew to do it.

It's management hands to do it.

Yeah, it's the management. And I can certainly appreciate for you know, farmers who are, it takes on another risk who are already sort of, you know, working very long hours, not maybe, you know, definitely not getting financially rewarded the way they should. That, that is, yeah, that is easier said than done. So I can certainly appreciate, appreciate that part of it that it's easy to talk about as opposed to doing it. But yeah, that is aligning incentives also. And I think part of those incentives should be aligned on from sort of, you know, statewide or government perspective that you are being can be rewarded for risk or incentivized to take some of those risks and you know, as opposed to focusing on maintaining a status quo. Right. And sort of the high input monoculture model. So it's definitely easier said than done and it requires some shifts both on the ground and on the policy level. But yeah, if we are wanting to move towards agroecology, I think that is the way to do it is using new modern techniques, the knowledge that we have now, and kind of blend that with traditional wisdom on how we used to do it. Because you kind of knew, like you said, John, in wisdom, a lot of people knew that already. It's like, oh, if I have multi species, I actually see synergies and I'm able to produce more food per acre of land.

Stefan, this has been such a fascinating conversation. Where can people learn more about your work?

My Twitter handle isn't fleet PhD so it's my last name and the letters PhD and then also if you Google my name on YouTube, there's many webinars that I've given on the topic where I actually go through a series of slides. So for people that actually want to see some of the data in figures, that could be a good one. And then also my Google Scholar profile, which is just. If you type in Stefan Van Fleet Google Scholar, you can see the papers. We do make it an emphasis that we make our papers open access. It means I have to sell my kidney every time I do so, but because the open access fees are. Yeah, that's another whole nother thing in academic publishing is that, you know, you have to pay a few thousand dollars for your paper to become open access, otherwise it becomes behind a paywall. And then only 100 of my colleagues read it. And so we try to do that as much as possible. And yeah, other than that, that's, that's probably some, some main things and you know, people can probably find my, my contact information, my email online and always happy to, to, to engage and in a, in a friendly and respectful way, even if people don't disagree. So. And which I love to hear too.

Yeah, those are going to be some wonderful resources. And for all of our listeners, we'll link to those in the show notes, which you can find if you go to the Regenerative Agriculture podcast website. All those show notes are linked and we'll have links to the useful resources. So, Stefan, thank you. Thank you for sharing your wisdom, your knowledge, your experiences. I've really enjoyed this conversation and I look forward to having more with you again in the future.

Thanks so much, John. It was a pleasure.

The team at AEA and I are dedicated to bringing this show to you because we believe that knowledge and information is the foundation of, of successful regenerative systems. At aea, we believe that growing better quality food and making more money from your crops is possible. And since 2006, we've worked with leading professional growers to help them do just that. At aea, we don't guess. We test, we analyze and we provide recommendations based on scientific data, knowledge and experience. We've developed products that are uniquely positioned to help growers make more money with regenerative agriculture. If you are a professional grower who believes in testing instead of guessing, someone who believes in a better, more regenerative way to grow, visit advancingecoag.com and contact us to see if AEA is right for you. Thank you for listening and we look forward to working with you.