Episode #13 Thinking Small and Big - Microencapsulation with Robert Langer
Dr. Robert “Bob” Langer joins us to discuss his work microencapsulating probiotics, micronutrients, and even human cells. Microencapsulating is the scientific process which creates a protective barrier around a cell and has been a lifesaving technology for a variety of conditions. Researchers are just on the cusp of nano-encapsulating technology. Dr. Langer, a chemical engineer and Institute Professor at MIT, has been called “the Edison of Medicine” by Times for his breakthrough innovations. He has over 1,350 patents and it’s estimated that over 2 billion people worldwide have been impacted by his innovations. From an early career as a chemical engineer working in Boston Children’s Hospital, where he developed the world’s first angiogenesis inhibitor (a medicine that prevents cancer growth by starving tumor blood vessels) to his present-day work developing a novel mRNA COVID-19 vaccine, Dr. Langer’s career has been full of innovation. Dr. Victoria Maizes and Dr. Langer discuss how cross-discipline collaboration in the sciences and diversity play an important role in innovation. Dr. Andrew Weil and Dr. Langer discuss how microencapsulating probiotics will improve gut health and how microencapsulating nutrients could yield better long-term health outcomes in populations lacking nutrient dense foods. We also discuss tissue regeneration, the process of growing new skin, which is already being applied to treat burn survivors. Dr. Langer’s scientific contributions are testament to what’s possible when you think outside the status quo and nurture imagination.
Please note, the show will not advise, diagnose, or treat medical conditions. Always seek the advice of your physician or healthcare provider for questions regarding your health.
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Dr. Victoria Maizes: Hi Andy. Robert Langer: Hi Victoria. Dr. Victoria Maizes: So today's guest is not an integrative medicine doctor or author or personality. He is actually an MIT scientist, chemical engineer. Dr. Andrew Weil: A chemical engineer. Dr. Victoria Maizes: How did you first hear of him? Dr. Andrew Weil: You know, I was invited to be on the scientific advisory board of a company that he started called Vitakey and Robert Langer this is just the latest in a series of very innovative projects. Dr. Andrew Weil: This one is looking at ways, micro encapsulate, nano encapsulating, micronutrients, probiotics, and other things that the body might need to make them more available and delivered them in better ways. Dr. Victoria Maizes: It's interesting. You say that because you think, you know, you can take that capsule by mouth and all is fine. But it turns out all is not so fine. Dr. Andrew Weil: Well, as you know with probiotics is a great question as to whether they even get to where they're feeding, you know, do they survive passage through the stomach, to the actually colonize the intestinal tract? Dr. Andrew Weil: Probably in many cases they don't, and here's a new technology that may make that possible. Dr. Victoria Maizes: Well, let's get Dr. Langer on. Dr. Andrew Weil: Okay. Intro music [00:00:00] Dr. Victoria Maizes: Dr. Robert Langer is one of 12 Institute Professors at the Massachusetts Institute of Technology. Being an Institute Professor at MIT is the highest honor that can be awarded to a faculty member. He has written nearly 1,500 articles, which have been cited more than 300,000 times. He has over 1,300 patents worldwide and has won more than 220 awards. Forbes magazine named Dr. Langer is one of the 25 most important individuals in biotechnology in the world. And it's actually estimated that more than 2 billion people worldwide have been impacted by Dr. Langer's biotech innovations. We're so delighted to have you welcome, Dr. Langer. Robert Langer: Well, thank you. It's a pleasure to be here. Dr. Victoria Maizes: So I'm going to be informal and call you Bob and ask about the beginning of your career. You began as a chemical engineer at Boston Children's Hospital in the 1970s. And at that time it was really quite unusual for a chemical engineer to work in a hospital. How did that happen? How did that end up being your start? Robert Langer: Yeah, well, that's a very good question. So when I was getting my doctorate at MIT in the early seventies, you know, there were these gas shortages, I guess, and pretty much all my classmates and friends, you know, would get jobs in the oil industry. So, I thought, you know, I do what everybody else did. So I interviewed at those companies and I actually got 20 job offers from oil companies four from Exxon alone. And I wasn't that good, but you know, they have a lot of openings. At any rate, you know why it wasn't very excited about that. And as I, you know, I mean, when I was there, it was actually okay. But then I fly back home and I be thinking about what they said. And they said, you know, if you could just increase the yield of this one petrochemical by 0.1%, they said that would be great. You know, it'd be worth billions of dollars. But to me it seemed like what was the impact of that? And so, I started thinking about other things that I might do. And one of the things I did when I was a grad student is I helped start a school for disadvantaged kids, high school kids, the Group School. And I got very involved in creating new math and science curriculum and chemistry curriculum. And one day I saw an ad actually at City College of New York to do that, to do something like that. And I was very excited. I wrote them a letter applying for a job, but they didn't write me back. But I liked the idea. So I found all the ads I could to develop, you know, a new chemistry curriculum. and I, anyhow, I wrote about 40 places and none of them wrote me back. So then I started thinking, well, how else can I help people with my chemical engineering background? And I thought about medicine. So I wrote for a lot of hospitals and medical schools. And they actually didn't write me back either. But then one day I walked into the lab and one of the older guys said to me, said, Bob said, “There's a surgeon in Boston named Judah Folkman at Children's Hospital. And he said, sometimes he hires unusual people.” You know, he thought very highly of Dr Folkman. And I won't say what he thought about me, but anyhow, I wrote to Dr. Folkman and he was nice enough offer me a job. He was a very, very famous guy and… But I didn't know that because I didn't know the area, but that, and you're right I was the only engineer in the hospital, but it was a transformative experience for me. Dr. Andrew Weil: Judah Folkman was one of my teachers when I was a student at Harvard Medical School. Robert Langer: Is that right? Wow. Dr. Andrew Weil: And I had some wonderful interactions. I got to present him with an award, much later after he had retired, but he was one of the main developers of anti-angiogenesis therapy for cancer you were involved in. What was your involvement with that? Robert Langer: Yeah, so that's a great question. So you're absolutely right. So when I came Dr. Folkman had this theory that if you could stop blood vessels, you could stop cancer. But as you know, from being there, it was very controversial. Everybody told them it was wrong and of course, I thought it was great, I didn’t know any biology, I thought it was a terrific theory. So my job was to do two things, one to prove it was right, and to actually isolate the first angiogenesis. So he and I wrote a paper in Science actually in 1976, which is the isolation of the first angiogenesis. And, also developed a paper in Nature at that same time, which helped set the stage for bioassays for all future angiogenesis. And that actually involved the drug delivery systems, the slow release polymers and others, things that we developed. But, he was a wonderful man. Dr. Andrew Weil: What's the status of that therapy now in cancer treatment? Robert Langer: It's gotten to be incredibly broad. Well, by the way, it's, it's, it's a very good question for several reasons. First it took 28 years from the paper he and I wrote in 1976 in Science before the first angiogenesis would get approved, but that one that got approved in 2004 by Genetech was Avastin. And that's one of the most widely used biotech drugs in history. And not only that many other angiogenesis inhibitors have been approved for different kinds of cancers. And then for eye diseases like macular degeneration and diabetic retinopathy, you know diseases in the back of the eye where there's abnormal vascularization. There was really no pharmacologic treatment. And now because of these inhibitors, drugs, like Eyelea and Lucentis, that actually can even reverse. They're the only pharmacological treatments for those diseases of blindness and they can reverse it in some cases Dr. Andrew Weil: I want to talk to you mostly about your current work with micro encapsulation of micronutrients and probiotics. Before we do that, I know you're also involved in the development of a vaccine for COVID and I wonder if you could tell us about your work with that and also where you think we are in terms of when we'll have an effective vaccine. Robert Langer: Yeah. Well, one of the things that we've done is we've started a number of companies. I mentioned, we develop ways to deliver different molecules with micro particles, the nanoparticles. So in 2010, I helped start a company called Moderna And the idea there was to create new drugs based on what's called messenger RNA. And there's a central dogma, you know, as you know, the DNA makes RNA makes proteins, but the key to making messenger RNA is modifying it the right way so it won't cause any type of bad response. So at any rate, what Moderna has done. I helped start it and I'm on the board of directors and scientific advisory board, but we now have about a thousand people and they have 14 different drugs in clinical trials, a number of vaccines. But the beauty of it is that if you put messenger RNA in a nanoparticle and inject it and inject it what does is rather than taking an activated virus or a protein, which might take a year to make and may have side effects here you could just give the RNA and the body is the factory, right? Because the body has all the machinery to take the RNA and make the protein. So at any rate, that's what Moderna’s done. They have RNA against what's called despite protein of the coronavirus. And now it's in, you know, really advanced the phase three clinical trials. And I mean, my hope is that you know, later this year there may be FDA approval. There still, I mean, it's, you know, it's too early to know, but I'm optimistic that that will happen. Now, certainly the earlier trials, the phase one and phase two trials have gone well and, and quite a bit, it's been published in new England Journal of Medicine by our collaborators at NIH. So when it will be widely available, that's harder to say. And of course it's not just Moderna that's working on it. You know, Johnson and Johnson's working on them, you know, AstraZeneca's working on them, Pfizer's working on it, but I think we need all of it because there's, you know, we want to help people in the US and but also all over the world. Dr. Victoria Maizes : So any lessons from the two extremes, you just described 28 years to go from an idea to, Avastin, something on the market with that theory made real. And now under a year, perhaps, for an mRNA vaccine, which I think is the first time mRNA is being used as a vaccine. Robert Langer: That's a very good question, but what's happened is it's interesting. So Moderna actually has eight other vaccines in clinical trials. So, so, and of course the work to lay the foundation on messenger RNA, you know, goes back at least not only our work till 2010 when we started it, but other people's work, including my own on delivering RNA back to the 1970s, and other people's work Derek Rossi to Reisman and others who have done work on RNA, you know, back in the early 2000’s. So it does build on, on, on the academic work as, as it often does, but, but you're right the foundation one having had that foundation, which obviously has taken awhile, then we were able to move very, very fast. Dr. Andrew Weil: So let's talk about microencapsulation, can you tell us what it is and what the potential applications are? Robert Langer: Well, like I said, one of the, well, so one of the areas of micro capitalization or nano encapsulation is just what we talked about, you know, delivering RNA. But one of the things, and of course we've done a lot on delivering different drugs through microcapsules to make them last longer. You know, have less side effects, and be more effective. And, and those kinds of techniques are widely used. But one of the things that, that we've done, which, might be relevant to a number of things that you've done and, and others is, the Gates Foundation has given our laboratory funding to help people in the developing world, who have various nutrient deficiencies. And one of the classic has been a iodine deficiency, but the way that, and the way that that was solved was that you could substitute iodine for chloride in a salt, you know, sodium chloride not sodium idodine. I done now that that's easier because it's in the same place in what's called the periodic table. But when bill Gates and his colleagues first came to see me in 2012, I believe, what they said, well, you can't do that for like iron or vitamin a or zinc or anything else because they're not in the right place in the periodic table. And some of course are not elements at all. So he said, can we come up with some way to solve that? And what we thought is maybe we could make a salt or something else where we might capsulate all these things. Now the particular challenge that the Gates Foundation was thinking about was you know, if you look at the customs, you can't change people's habits as much as we might try. So what he wanted to be able to do was could you put it in boiling water, any of these things in boiling water for two hours and boil it a hundred degrees C and the nutrients should not come out of the salt or the micro capsule. It shouldn't change color and it shouldn't change tastes, but then when you eat it which is not a hundred degrees, C it's a 37 degrees C it should all come out within an hour. So that might sound impossible. How could you do that? We, Ana Jacklenec in our lab and our team. We figured out a way to actually take FDA approved materials and do just that with 11 different micronutrients. And, and so that's very exciting and a couple of efforts to have stem from that to try to bring this into the developing world, the Gates Foundation funded a what's called Particles for Humanity to try to make large quantities of Vitamin A, a at a reasonable cost and, you know, which can be put in say bullion or things like that. And then with Wayne and Catherine Reynolds we've started a company called Vitakey to encapsulate all kinds of things that might help people have better health. And in fact, I think you're one the advisors. I mean, the technology is quite powerful because you can encapsulate anything. And like I say, it's very stable, under different kinds of conditions. It's very stable in terms of not just temperature, but also light, we've compared it to existing ways of where people have tried to make that various ingredients and it's, you know, it's much more stable and yet we can still release it when somebody eats it. In terms of tastes like we've done, we've put it in bread, for example, at the required daily amounts. And it doesn't change the color of bread, even though iron itself is pretty dark and it doesn't change the taste either, you know, and it's fine. I’ve eaten it and Bill Gates has eaten it. Dr. Victoria Maizes: So is the secret stomach acid? Is that what ends up leading to the release? Robert Langer: Very, very good. That's exactly right, what we did is we, we sreened about 50 different materials that were known to be safe. And we found one that a family actually, cause you can actually change the pH depending on what the goals are, but, but you can make a pH sensitive system so that it could be an absolute solid, at a neutral pH. And yet when it gets to say acid, like you just said, simulated gastric acid, it'll dissolve completely. Dr. Victoria Maizes: Actually, I am curious where some of these ideas come from. I know that in an earlier talk that you gave you mentioned that before chemical engineers were partners with doctors, doctors would go home and sort of scrounge around and find something that could solve a problem. You gave the example of the first artificial heart was inspired by a woman's girdle and actually initially constructed by a women's girdle and the cardiac surgeon took it and I guess sterilized it and must've modified it. But where are your ideas coming from? Robert Langer: Yeah, well, first what you said is absolutely right. That was Bill Pierce. I was on an NIH study section with him and he told me that story and I read it in Journals. And that's true not only for the artificial heart, the same thing is true for breast implants. Actually, one of those was a mattress stuffing. And, and, and what are called, vasograph. So sort of certain types of artificial blood vessels, and it was a surgeon in Texas going to a clothes store to see what he could sew with. Well, the way I thought about it was a little bit different because like I say, I had a different background, I’m a chemical engineer. So the, one of the things you learn in chemical engineering is what I'll call chemical engineering design. And so what I started thinking about was rather than take these materials that already exists. What would be an ideal material from an engineering standpoint, chemistry standpoint, biology standpoint, you know, and then we try to put the criteria down, draw these things and less chemical structures on the blackboard and then actually go into the lab and try to synthesize. So it's a totally different kind of approach, but I think it offers the ability to make things that are potentially much safer and have far superior properties in different ways. Dr. Andrew Weil: Aside from micronutrients the other application that fascinated me was using this encapsulation technique for delivering probiotics. Can you tell us something about that? Robert Langer: Yeah, absolutely. So again Ana Jacklenec and others in the lab, we've put probiotics in and given it to animals and we can do that as well. I mean, again, it's stuff, you know, different types the designs that we've used in terms of, of putting them in polymers. And by the way, we've published all this stuff too. We have patents on it, but we've published it all in journals like Science, Translational Medicine, and Advanced Materials, but you're absolutely right. We can I really feel like you can…I mean, I don't want to overstate, but I feel quite confident that we can encapsulate almost anything and then, and then deliver it, you know? And, and that goes from things like DNA and RNA, which enabled like Moderna and other things to, to, to these nutrients that were talked about in probiotics, which Vitakey can do. Dr. Andrew Weil: And you mentioned the possibility of a wound treatment using topical encapsulated probiotics. Robert Langer: Yes. You could do that too. you're absolutely right. You could do any of those kinds of things, theoretically. I mean, you have to make sure that your animal models are good. Certainly with things that you're already eating. I mean, that, that we feel we can just do better and make them taste more stable and, and, and things like that. And maybe do other things that would be useful, like give it a longer lasting flavor for example, Dr. Victoria Maizes: You also are using this technique to address a really serious problem, which are these resistant infections that are resistant to many, many of the existing antibiotics. And that has been something you've used as well with wounds that have MRSA, Methicillin-resistant Staphylococcus aureus. Are you actually using a combination of antibiotics? Are you using probiotics? Are you using novel treatments? How, how are you approaching that? Robert Langer: Yeah, well, we'll do a combination of, of using different substances that have been used, but hopefully delivering them better and delivering them longer and in the best profile and making sure that they're stable or not destroyed right away. Dr. Victoria Maizes: I know that some of the early thought process of these very targeted ways of delivering is when you give someone a medicine by mouth of course the liver has to break down. And that means you usually have to use a higher dose because things are inactivated and maybe you can't really get the ideal dose to the particular place you want it because it could be toxic to the body in general. So I think this very targeted delivery system is really fascinating. Robert Langer: Well, thank you now. No, we're very excited about it and I hope that we'll do a lot of good. You know, we've already tested it on people. I mean, we, we've done collaborative studies with, at ETH and, you know, everybody seemed to be very happy with the results and everybody did fine healthy wise. Advertisement: “Body of Wonder is Brought to You by AWCIM + COVID-19” Dr. Victoria Maizes: So I have a question really, for both of you, in many ways you're both pioneers in your specific fields, and I know that people probably put energy into dissuading you from following what you clearly believed was possible. I'm sure that some of the career steps you took people considered risky. I mean, you could have gone into the oil field and just made billions of dollars for the companies and probably a good amount of money for yourself. What is it, do you think that was innate in you that made you go in this different direction? Even in the face of a lot of dissuasion. Robert Langer: Yeah, Andy, do you want to go first or should I… Dr. Andrew Weil: Bob I'll just tell you a story about Judah Folkman. You know, he was inducted into the Academy of Achievement that Wayne and Kathy run. And they asked me to present him with the award. And afterwards he said to me, you know, at Harvard Medical School, the faculty say they try to train students to think for themselves and now that one of them has done it, they don't like it. I thought that was a terrific compliment. I think that's right. But he's right. Robert Langer: I think that's right. But he's right. Yeah. He's right. That's a great story. Well, he was a wonderful role model. And in every way. I mean, it's related to me. I mean, I had the simple idea that I wanted to do some good, I guess, and I didn't feel excited about going into the oil industry And I am doing things like teaching I couldn't go in right away. And actually what you said is also right. You know, even after I worked in Dr. Folkman's lab and we published these things, which have turned out both the angiogenesis work and the drug delivery work, which have both turned out to have a big impact on the world, you know, a lot, I wanted to get a faculty job so I applied to chemical engineering departments. And because that's what I am. And no chemical engineering department in the world would hire me. They kept saying the bio stuff you're doing doesn't make any sense in a chemical engineering department. So I didn't get any jobs there. But then, then what happened was, you know, I, I tried to get grants for what I did and actually the first nine got rejected very badly because people said again, how could a chemical engineer do a cancer research or anything? And then, I ended up getting a job in an nutrition department. And the reason I got it was Dr. Folkman knew a man named Nevin Scrimshaw, who was a, really a well-known nutritionist. And he was head of that department, but he was the kind of department head that was more what I'll call a benevolent dictator in the sense that he liked me so he hired me, but he didn't ask the rest of the department what they thought, which would have been okay if not the fact that the year after I joined the department, he left so pretty much the entire senior faculty gave me advice and their advice is I should leave too. So that was a very discouraging. And then, and they kept saying this idea of encapsulation and drug delivery, you know, is ridiculous. You shouldn't bother doing it that you know, and you better start looking for another job. Dr. Victoria Maizes: Wow. And yet, I know in your lab, at MIT, the Langer Lab, you really value diversity. And it seems to me, the world has maybe come to value collaboration across fields more. I mean, we had our Center for Integrative Medicine, do work with biomedical engineering to do projects around M health. So I think the world has caught up a little bit. What's your experience? Robert Langer: I think it has caught up a little bit too I mean, it used to be that, you know, I mean, just as an example, like when I went to college, you know, there was a building for chemical engineering, a building for English, a building for biology, you know, now at MIT, what we've got there, did they even built a building like the one I'm in now has like seven different types of engineers and it has biologists. So I think that slowly it's changing. I mean, one of the things I like to think is that we contributed you know, what what's happened is when I was a start trying to find jobs or all these chemical engineering departments. And like I say, they didn't think bio things were important now, you know, half the bioengineering, half the chemical engineering departments in the country, or close to it, have bio in their name and 400 people from our lab are professors. I mean that have graduated over the years and they've made a huge difference because they keep training others and so forth. And so, but it's taken a while, but I agree with you that things are starting to move more and more in that direction. I think it can still move even further. Dr. Victoria Maizes: Yeah, in medicine, also it's quite siloed and there is a saying that, people who train together and practice together. And so, clearly not everybody trains together. You may not have any training, for example, with a physical therapist and then you don't have a clue, let alone someone who does acupuncture or nutrition, and you really don't know how to refer to them. Robert Langer: Right? No, I agree. Dr. Andrew Weil: Well, let me say Victoria, I'm licensed as a general practitioner, which I'm very proud of. That is a dying breed. And the great problem in medicine is that we have so few generalists and so many specialists often to the detriment of patient's health. I cannot tell you how many patients I've seen, who have seen so many specialists and no one has a big picture view. No one is able to put this all together and see what might be the root cause of a problem. I think we have a terrific news for more generalist in medicine and probably in science also. Robert Langer: No. I agree. I think that's well said. I agree with you. Dr. Victoria Maizes: Well, I'm trained in family medicine and I also consider myself a generalist. I often wish for the old Renaissance thinkers, you know, the people who are trained in medicine and engineering and Latin and music. And it seems that these days we don't do that. I mean, the, the disciplines have gotten so enormous, so maybe the best we could hope for is that people really do learn some common language and are able to collaborate effectively. Robert Langer: Yeah. When people ask me, you know, what was important in my career, I always say that experience at Children's Hospital. Cause I said, cause I said to them, you know, I knew I was able to know a little bit about chemical engineering and a little bit about medicine and just put them together in different ways. But most people haven't had that. Advantage or whatever you'd call it. They've probably learned just one or the other and point that you made about materials. The question you asked me, that's a great example. Clinicians thought about it, like “what's in my house that I can use” and a chemical engineer might say, well, but maybe you could synthesize. Dr. Andrew Weil: Bob, is there an idea or project that you're just beginning to work on that you're excited about now? Robert Langer: Well, there, there are a number of them. You know, one thing we haven't talked about that we do a lot of work on that I'm very excited about, about another one of the people I met when I was in two to Folkman's lab was a Jay Vacanti and Jay became head of the liver transplant program later at Children's Hospital. And he's now at Mass General. And one of the things he pointed out to me in the early eighties was he had was feeding a little babies here, dying of liver failure. And you said was some way that he and I could make organs or tissues from scratch. So we came up with this idea of it's now called tissue engineering. And it basically, it would involve putting the right kind of cell while the initial thing we thought about was putting the right kind of cells on, materials that I might design and do it in a certain way and grow it in a bioreactor. But today that technique has been FDA approved for making skin, for burn victims and people with diabetic skin ulcers, but we're working in the lab on a number of things. And my students have worked on a number of things as well. So in the lab and actually in some spinoff companies, you know, one of my students is making blood vessels for people with heart disease, because you can't make small diameter blood vessels you have to sew them in. Another couple of my students are working on ways of restoring hearing loss. Cause we found some molecules that can cause hair cells to proliferate. Another will find to make new spinal cords, another group making up a pancreas. And again, some of these things that also led to you know, cause people do animal testing and human testing, but now you can try to, and again, this is an early stage, but make organs and tissues on a chip. So one of my other postdocs, who actually went to the, well now he's a professor at MIT, geo traverse, he, and, and, and we, we made a like a gastrointestinal track on a chip. And another couple of my students made a heart on a chip. And, and then even to the last thing, you know, is that one of my students is a professor in Israel. She's a STEM cell expert and she's actually using this technique to make meat from scratch. And then there's a company in New York that's making leather. So, so this is a whole area we're trying to develop. The science, furthermore, that I, that I think, you know, will hopeful be very, very important someday. Robert Langer: Well, I'd love to hear about the major things that you're excited about and that you're doing. I mean, of course I've read Andy's books a number of years ago, and I'd love to hear about what you're doing and, you know, what the things you are you're doing that you're most excited about. Dr. Andrew Weil: Bob, One of the areas that I think a mutual interest we've done a lot of work in the area of integrative mental health. We think there is urgent need for a new, a new paradigm to replace the biomedical model in psychiatry that has been very limiting. And one aspect of this new paradigm would be looking at nutritional influences on mental health. I think that's quite relevant to some of the work you're doing with Vitakey, I put you in touch with several people who've spoken at our conferences on integrative mental health, about using a targeted micronutrient delivery to really improve brain function and emotional wellness. And I think that's a very important area for the future. Robert Langer: Well, I'm very glad you said that. I mean, I think you're right. In fact, the other question I was going to ask you are even more ideas about what Vitakey could encapsulate that can really change people's lives, but mental health would be fantastic. And that's great a great, great point. Dr. Victoria Maizes: You mentioned your work in developing nations and in theory, because we have such abundance, we wouldn't have micronutrient deficiencies in our country, but we do, for a lot of reasons, including, we call it the SAD diet, which is the standard American diet. So the, you know, the, the sad diet pretty unhealthy, but other people are really worried that we've depleted our soils because of all of the pesticides and herbicides that we've used on it over time, that the soil is just not as nutrition, so nutritious. So even if you grow something, you know, and you think you're serving someone healthy food, it's still may not have all the magnesium that used to be, for example, in the plant. Robert Langer: I say, well, those are both interesting. I mean, I had never thought about the last one. That's a great point. So magnesium for plants. That's interesting. Dr. Victoria Maizes: Well, I mean, there's a lot of, that's one of the nutrients that's thought to be deficient at this point, but there are a lot of the, of the nutrients that you would expect people to have adequate amounts from just a nutritious diet. And now that's more a questionable. Robert Langer: No I wasn't even aware that that's, that's really important. I mean, that's very interesting. Dr. Victoria Maizes: I have a vice question for you. We like to ask our guests here we are talking about health and healthy behaviors. We like to ask our guests if there's one vice, a secret vice that they'd be comfortable sharing with all of the listeners for this program. Dr. Andrew Weil: A guilty pleasure. Robert Langer: Well I don’t know if it’s a vice or not but chocolate for now. Dr. Victoria Maizes: We consider that healthy pleasure, not a guilty pleasure. Robert Langer: I love chocolate while I, well, when I probably eat too much, you know, it's funny our place in Cape Cod. There's this great candy store, Ben and Bill's that I keep going to and getting all these dark chocolate with maple cream or wintergreen cream. There's no question. Chocolate. Chocolate candy and ice cream. Those would be my two, two vices. Dr. Victoria Maizes: Yeah. In the field of nutrition. Robert Langer: Yea like healthy ice cream. Dr. Andrew Weil: Thank you very much for participating. It's a pleasure to meet you virtually and hear about your work. It's very exciting. Robert Langer: Well, it's mutual. I looks great talking to both of you and I mean, really that you've done such amazing stuff and, you know, just really appreciate your help and everything. Dr. Victoria Maizes: Well, I just have to second Andy, you know, clearly you have had an impact, which was the goal you had setting out on the lives of so many people and my guess is generations and generations more so thank you for your work. Robert Langer: Well, we're trying, and we look forward to collaborating with you both. Dr. Victoria Maizes: That'd be terrific. Robert Langer: Thank you. Alright, bye. Bye. Bye. Advertisement: My Wellness App