Study: Nutrigenomics far outperforms Keto for weight loss.
Last updated on

#10 – The Future of Food Sensitivity Testing, Curing IBS, Rethinking Gluten Free Diets, and the Genetics of Coffee Metabolism with Dr. Joel Evans, M.D.

Food sensitivity testing is a controversial topic. Even among our team here at Gene Food there is disagreement, with some doubting the science behind the standard IgG panels and others swearing by them as an essential tool for healing autoimmune disease. However, debates notwithstanding, there can be no doubt that most IgG food tests on the market today register false positives with the result being overwhelmed consumers staring at a list of 20-30 foods that are now “off limits.” Our guest today is hoping to help change all that by making food sensitivity testing more accurate. Joel Evans, M.D. is one of the leaders of the integrative health movement. He is a board certified OB/GYN and international lecturer, is the Founder and Director of The Center for Functional Medicine, where he practices integrative functional gynecology.

Dr. Evans was honored to speak at the United Nations in March 2013 on the topic of Prenatal Origins of Violence, and he now serves as UN Representative and Chief Medical Advisor for OMAEP – World Organization of Prenatal Education Associations. In addition to his integrative practice, Dr. Evans serves as medical director for KBMO Diagnostics, a company that is producing the 2.0 version of IgG food sensitivity tests. KBMO has introduced new technology aimed at not only finding foods that register an IgG response, but that also cause inflammation which can damage gut health. In today’s episode, we learn about the new scientific developments aimed at increasing the reliability of IgG tests, we discuss a promising study Dr. Evans did on patients with IBS, when gluten free diets aren’t necessary, the health benefits of coffee, how food sensitivity can affect the development of our children and much more.

Listen on Google Play Music


This Episode Covers:

  • Traditional food sensitivity tests and false positives [7:00];
  • Zonulin and when intestinal permeability is a good thing [10:55];
  • IBS discussion [13:30];
  • Who needs to be on a gluten free diet? [21:30];
  • Autism, failure to thrive, and food sensitivity in children [32:00];
  • Genetics of coffee plus acid alkaline balance [38:00];
  • Epigenetics and food sensitivity [45:00]


The “I did great with gluten in Europe” story could be linked to the glyphosate that is so prevalent in American foods.

I did a blog previously on some of the tests that are used to identify gluten sensitivity.

More on glutathione and superoxide dismutase. Dr. Evans also mentioned MTHFR and COMT.

My blog on urine PH and how that metric changes with diet as well as more on coffee metabolism.


John: Welcome to the “Gene Food” podcast. I’m your host, John O’Connor. Hey, guys, before we start with the introduction of the episode, we wanna give you the usual rundown of what we’re doing at “Gene Food.” We have more content coming online at, which is our sister site. That’s the place for nontoxic products and then, of course, our custom nutrition plans. You could think of them as the Myers-Briggs for nutrition. We have an algorithm that will divide you into 1 of 20 different diet types of based on your genetics, and it’s intended to give you a foundational tool to start from as you try to figure out the diet that’s right for you. Today’s episode is as usual. You know, I’m gonna say this, it’s a good one. We have Dr. Joel Evans, MD. Dr. Evans is a board-certified OB-GYN, and he’s an international lecturer. He’s the founder and director of the Center for Functional Medicine in Stanford, Connecticut where he practices integrative functional gynecology.

Dr. Evans was honored to speak at the United Nations in March of 2013 on the topic prenatal origins of violence, and he now serves as a United Nations Representative and Chief Medical Advisor for the World Organization of Prenatal Education Associations. We felt really excited to have Dr. Evans on the show because he’s also the medical director for an organization called KBMO Diagnostics, which is a company that is putting together the next generation of food sensitivity testing. So for those of you who aren’t already aware, the traditional food sensitivity test, it’s different from food allergy. In a food allergy, you have an immediate reaction. Your body just instantly responds, like people that have peanut allergies. But a food sensitivity reaction is usually delayed. It can be delayed for, you know, 24, 48 hours. And the thinking is, is that these delayed sensitivities cumulatively cause inflammation. And traditionally, the way that they were tested for, there was a lot of false positives that would come up because anything that stimulated antibody activity was thought to be food you were sensitive to.

But the 2.0, next generation version at KBMO looks at these traditional food sensitivity antibodies called IgG, but it adds to it something called a complement factor, which is another marker of inflammation. And the idea is, is that when you take a test like this, you show the foods that your immune system is reacting to that are also causing inflammation. And so, it’s very interesting to hear the science behind the latest generation of food sensitivity tests with Dr. Evans. We also get into a whole bunch of stuff like he did a study on IBS and was able to really help people with IBS using this testing protocol and some dietary changes. We talk a lot about gluten sensitivity and celiac, we talk about healing the gut, we talk about the development of children and how food sensitivities can be contributing to delayed development and certain anxiety and mental health issues with children. And we get into all sorts of stuff. So without further ado, here is Dr. Evans. So how did you get involved with KBMO? Because I know that you also have…you’re the founder of a functional medicine practice and you’ve done a whole bunch of stuff, the United Nations work, and really a lot of cool stuff. So how did you get involved with the KBMO Diagnostics company?

Dr. Evans: You know, so clearly I’ve been a leader in the functional medicine movement for years, and years, and years, and started using functional medicine in my practice in the late ’90s, started lecturing in the early 2000s for Metagenics. And what I ended up doing was, number one, becoming very aware of what the issues were for a need for food sensitivity testing and accurate food sensitivity testing. The awareness of a relationship between what people ate and their complex chronic disease was apparent not only to me, but to all functional medicine practitioners. The problem always was a great test where we could identify the foods that caused inflammation. And then I just happened to be walking through a conference and saw a KBMO booth, and the CEO, James White, happened to be there and I was talking to him, and it seemed very interesting to me because this was the only test that actually looked for a marker of inflammation.

So not just the immune system marker of immunoglobulin G, or IgG, but actually complement, which is a marker that’s used in the inflammatory process. And so, his test is the only one that positioned itself as a test to identify foods that caused inflammation. And as we all know in this world, inflammation is the main underlying process through complex chronic disease. So then I just tried it in my practice, and I ended up getting to the point where I was using this test on almost every single patient that I saw and I was incredibly impressed with the results and I was giving James feedback. And then it turned out that just around the same time, he had a vacancy for a medical director, and I actually invited myself to apply for the position because I felt so strongly about the test, and I’m sure he’ll tell you that my passion and excitement over the test was one of the main drivers for him deciding that I was the right one to become their medical director.

John: Cool. Yeah. So you saw it working. I think one of the things that’s really interesting about this test for the listeners who are kind of wondering, you know, people that will have tuned in will probably have some basic idea of food sensitivity testing, IgG markers, and then there’s this very kind of mixed bag of commentary on the IgG tests out there. People feel like they hit false positives. You know, some people, for example, our nutritionist on our team, Danielle, who does all of our recipes, she swears by the value of food sensitivity testing in her life in terms of a thyroid condition that she was dealing with that she’s written about on our blog. But this test is like a 2.0 version of that. So you mentioned this complement factor. Like how does your test differ from the traditional food sensitivity tests that are out there?

Dr. Evans: So the traditional food sensitivity test measures for IgG, and IgG is the main component of the immune system that works for a delayed reaction. The problem with measuring just IgG is that there can be a lot of false positives, meaning your immune system may have exposure to a particular bacteria, for example, and that bacteria cross-reacts with your immune system, and you then create an antibody response to the bacteria, which is appropriate, but it just shares the same molecular composition as a food, and then you’ll react to the food. And so, that can give you almost like a false positive. So the IgG tests, by themselves, usually display results for 20 or 30 foods that people have to avoid. And that’s hard to do in the real world. But what we do is we focus on not just the IgG reaction, but also a complement reaction. And a complement reaction is almost like the next step. So after you have an antibody reaction with the IgG, there has to be what’s called the complement cascade or another step in the activation of the immune process that happens to create inflammation, and those complement molecules will actually bind to an IgG molecule, and that tells you that that particular foreign substance is triggering not just an immune reaction but an inflammatory reaction. And that’s what we test for on the plates, is we look for IgG that is attached to complement. And so, that tells us that if a food, and we keep the food in a plate and then we throw someone’s blood on top of that food, and if the antibody with complements sticks, it means that they are producing an antibody complement response to a particular food, and then we measure the intensity of that reaction. And if that reaction is severe, then we know that they have to avoid that particular food. And normal IgG testing doesn’t do that. You end up with too many positive foods, not all of them which will require that you eliminate the food. There’s no way to differentiate the foods you have to avoid on the test report, and it just gets very difficult and challenging for the patient.

John: So what I hear you saying is that in a food sensitivity test like you could go order on the internet, you’re gonna have foods that are gonna show this IgG reaction, but those foods are not necessarily driving inflammation.

Dr. Evans: Exactly.

John: Whereas when you add this 2.0 piece and you have not only the foods that are stimulating the immune system, but the foods that are stimulating the immune system in a way that causes inflammation. And is that because of the fact that eating these foods is upregulating the production of zonulin?

Dr. Evans: Okay. Well, you know, zonulin is very much related to the food sensitivity issue, but it’s slightly different. So zonulin is a protein that is secreted by the body in order to increase intestinal permeability. It’s something that we have in our system because we need it. So there are times that we need to increased intestinal permeability. And the most common reason for that is, if there’s an infection, for example, and it’s irritating the gut, we don’t wanna continue to have these bad bacteria that can damage the lining of the intestine. And so, we actually want to open those gates in between the enterocytes so that these particular bacteria can come in better contact with their immune system so that we can destroy them. But zonulin is also secreted when there’s inflammation on the gut wall, and we can’t always recognize that it’s from a bacterial infection. And so, food sensitivities lead to secretion of zonulin and lead to leaky gut. And at the same time, you have a bi-directionality associated with this process, such that leaky gut leads to more food sensitivities because you are exposing the immune system to more food antigen. So when you have absolutely no increase in zonulin and you have a healthy gut, about 2% to 3% of food proteins still cross when they shouldn’t, and that’s why most of us have some amount of food sensitivity. When you have zonulin on board, that number increases. And when you do have leaky gut, you’re going to have an increased development of different food sensitivities. So food sensitivity are both a cause of and a result of leaky gut or increased intestinal permeability.

John: Right. And so, for the listener at home who’s like, “Okay, well, we’re talking about zonulin and all these different antibodies.” You know, this sort of a technical way to start off to set the foundation for why this test is different. This test is not an allergy test because as, you know, I’ve heard you do previous interviews and read the literature that you sent over, so in an allergy, you have this immediate anaphylactic reaction. And in the markers, you’re testing for, you’re looking for something that’s delayed. There is this huge spike in autoimmunity in the U.S. right now and you guys have estimated that these delayed food sensitivities that are resulting in inflammation are having a massive impact on the economy. So I was really interested to see that… I wanna talk about your IBS study. You guys are estimating… I don’t know where you got this statistic, but $30 billion damage to the economy based on just IBS, and that’s not even cutting some of the other one.

Dr. Evans: IBS alone. Yes, yes.

John: Yeah. IBS alone.

Dr. Evans: Yeah. And so, what happens with IBS is IBS really is a diagnosis for GI symptoms for which a cause can’t be identified. And IBS can come in the form of constipation, it can come in the form of diarrhea, it can come in the form of alternating constipation and diarrhea. So one of the beautiful things about our test is that we can use it for patients that have IBS symptoms or a diagnosis of IBS. And what our study has shown is that with IBS, we have been able to reduce symptoms significantly better than the other types of food sensitivity tests that are out there. So there’s something called an IBS symptoms severity score, and we drop that IBS symptoms severity score better than any other tests.

John: Let me stop you right there really quick on that point. Sorry to interrupt. Because I was really interested when I was reading the study and I heard you do a previous interview. And I if you could just drill down on that for a minute in terms of the symptom severity, which symptoms you’re talking about specifically and how those are abating or improving based on this. Just kind of talk about, with your patients, the quality of life issues that they’re seeing with this condition.

Dr. Evans: Right. So the IBS symptoms severity scale, what’s so important about it is that it’s what we call a validated questionnaire. So it’s the same questionnaire that’s used in old different studies. So it’s important, if you’re ever studying something that you use a validated questionnaire, and the questionnaire looks for things like stool frequency, stool consistency, quality of life improvement, symptom reduction. So it really digs in detail about all of the problems that somebody that has an IBS diagnosis has in their life. And that’s why it’s such a good way to measure any intervention for IBS. And so, what we found is that we had a drop in our IBS symptoms severity score in our intervention group by 126 points, and you had to have a high number in order to get started. So most people had numbers in the 200s, which are very significant, so that means people that are on the severe side in terms of their symptoms. And so, with 126-point decrease is terrific. Now, the important point here is that we just… The control arm was really a healthy diet arm, and those patients got better as well. And so, they had a 46-point drop, which shows that there’s a nutritional component in terms of a healthy diet for everybody, but that means that there was an 80-point difference, so you could improve your effectiveness, essentially, 3 times as much by eliminating the foods that we flagged as foods to be avoided.

We also had a decrease in homocysteine. Homocysteine is an amino acid that is associated with problems to DNA, and heart disease, and depression, and anxiety. And we are very well aware of what we call the gut-brain connection. And so, by decreasing our homocysteine, that is something that wasn’t studied, but we have noticed, certainly in my practice, the effect on mood of eliminating foods that cause inflammation, because depression and anxiety are inflammation-related disorders. We also noted, based on inflammation, the marker C-reactive protein, which is a marker of inflammation, and we decreased our CRP significantly. So what we found with this study is that not only were the symptoms improved, but the biologic markers of homocysteine in CRP were reduced, and also office visits for problems decreased over 50% in our intervention group. So having lower physician visits means healthcare expenses, and we all know how important that is.

John: Absolutely. So much to unpack in all that. I found the fact that the homocysteine levels dropped. We talked about homocysteine in our MTHFR episode we did a little while back. I thought that was really interesting, that homocysteine and C-reactive protein went down.

Dr. Evans: Yeah. It really is.

John: You said healthy diet. That’s obviously like a very charged a topic out there in the nutrition world. So in this study, how did you define healthy? A healthy diet?

Dr. Evans: Well, it’s the kind of thing where we took away a lot of processed food, so not a lot of sugar, not a lot of processed food. We did not eliminate gluten. We didn’t eliminate dairy, so no food groups were eliminated, but, you know, things like alcohol, just things that would cause anybody to have a problem with their guts, so really mostly processed foods and smaller amounts of sugar.

John: In preparation for the podcast, I listened to some interviews you did and, you know, obviously, read your bio and read the literature you sent in. In one of the conversations you’d had with, I believe it was Kara Fitzgerald, I could be mispronouncing her saying her name slightly wrong. It’s interesting that the gluten wasn’t taken out. And mainly I say that just because of the fact that that’s such a widely accepted consensus view in most circles as you take out gluten. I think some people say that gluten will increase production of zonulin, it’s bad for the gut. And then you were talking about how, sometimes when these foods are removed, they can be reintroduced without an issue 60, 90, 120 days out after the body’s had a chance to heal.

Dr. Evans: Right. So I think there are two important points here that you made. The first, you sort of talked about gluten being a problem for everybody. And I think that that’s something that’s worth discussing because we as practitioners have to make that decision about recommending gluten elimination to our patients. And so, do we just cake a general philosophy and say everybody’s better off if they’re not eating gluten or do we personalize and individualize? And I think that that’s something that every practitioner has to decide on for themselves. I don’t think there’s only one right answer. But what I would say is that one of the main researchers in this field is a doctor by the name of Alessio Fasano, and he’s at Mass General Hospital. And Dr. Fasano actually is one of the main researchers in zonulin, and he is now on our team developing the next-gen zonulin test. So I’m very familiar with his work and he actually has a book out for the general public called “Gluten Freedom.” And, you know, when he talks about the problems with gluten, he says in his book that gluten is perceived by our gut immune system as a potential enemy, and an immune response is elicited by everybody to gluten, not just to people that have a gluten-related disorder.

You know, the book came out in 2014, and that is the basis that most practitioners say when they recommend universal gluten avoidance, that there is an immune reaction. But what Fasano also says is that he doesn’t believe that everybody to be off of gluten. Meaning… He says, “Yes, there’s an inappropriate immune response.” However, he likens it to what happens to bacteria that were exposed to bacteria and we create an immune response. But that doesn’t always cause ill health because we don’t lose that battle. So he says that patients that are genetically susceptible, and that’s the, you know, the HLA-DQ2, DQ8 patients. So patients that are genetically susceptible, they have to avoid gluten because they’ll develop a gluten-related disorder. Or if patients that have a sensitivity like we test for should avoid gluten. But he says, “If you don’t have the gene and you don’t have a sensitivity, it’s okay to have gluten.” But, again, I can understand both sides of this debate.

John: Absolutely. And then you get the people who say, “I went on vacation to Italy and I ate a ton of gluten. I ate all the past date, all the pastry, had an amazing time, and I felt okay.” So then you get that third camp who says, essentially, “It’s not the weed, it’s the glyphosate, it’s the way the wheat is processed. It’s all this stuff that’s in some of these low quality wheat products. If you’re eating, you know, a certain fermented bread, sourdough, you know, you could be okay.” But I think that’s a cool message.

Dr. Evans: It’s funny. I think it’s a great message. I had that exact same conversation with the patient on Wednesday who was really hitting me hard, saying, “I just came back from Italy and I had gluten every single day for two weeks.”

John: Yeah. And I love my life.

Dr. Evans: Right?

John: Yeah.

Dr. Evans: And what I would say is, and, you know, you’re asking really good questions and there are real subtleties to these responses, right? So this is where this concept of food reaction comes in because people can react to foods for different reasons, and it’s not just the immune system. So people can react to foods because of additives, for example. So you just talked about some of the pesticides that are used. So this really could be one of the reasons that people don’t react to what’s going on in Europe, is because foods are grown differently, the grains are grown differently, but also, it’s a different grain, so there are different molecules in there that potentially don’t trigger the reaction in people. But there is gluten there. So if you have, on a test, a documented gluten sensitivity, you’re still better off avoiding it, and the reason you don’t have symptoms is because it’s just a cleaner food.

John: Okay. Speaking of that, so we know if we get the food sensitivity test, that’s one way of measuring whether you have…trying to identify a sensitivity to gluten. What do you think about the tissue transglutaminase test where you could get, let’s say you’re somebody who… You know, I’ve corresponded with, like, mothers who’ve written on our blog who have said, “My son or daughter had negative celiac test,” which is, my understanding is it’s the IgA tissue transglutaminase IgA, and their IgA serum levels were measured and they were completely adequate, so they had plenty of IGA. But then we found this really high inflammatory score on the IgG. And when we then did a biopsy and looked at their small intestine, they had a lot of damage that was consistent with like a celiac type condition. So what are the tests that you would have somebody do in addition to your diagnostic panel to really try to zero in and say, “I do have this issue with gluten. I have the blood test,” and either sleep easy at night and start eating gluten or say, “I’m gonna cut it out in pretty much across the board.”

Dr. Evans: Well, I think that there’s really two main buckets of patients where I would answer this question, you know, a little bit differently. So there’s someone coming in optimal health, you know, looking for optimal health, and what do I do for them? And then there are those people that have either gut symptoms or some other chronic disease, and what do I do for them? So the easy thing for the person in optimal health is, I think it’s good to do a fit test because I think it’s good to know foods that cause inflammation so you can avoid them so that you can stay healthy. And then in addition, I do a HLA-DQ2 and DQ8 test, which is the genetic predisposition for celiac disease. So you can’t have celiac disease unless you have a positive genetic test. So I do the gene test, and if the gene test is positive, I say that they avoid gluten because those are the patients that celiac disease can develop and gluten sensitivity can develop.

So that’s that bucket. Then there’s the bucket of people that have either got symptoms of gut diagnosis or some other troubling symptom or troubling diagnosis. So then I wanna know what’s going on with them. And I think that a test profile that I just discussed, which is the HLA-DQ2 and 8 and the fit test, you know, plus or minus the zonulin are usually enough. However, if I have any reason to suspect celiac disease, then I’ll definitely order a tissue transglutaminase antibody. Now, that’s an interesting test, and also an anti-gliadin antibody. So gliadin is one of the main proteins in gluten. And so, that’s just another way to measure gluten sensitivity or an antibody towards gluten, but the tissue transglutaminase test is an interesting test because it measures an antibody to an enzyme in the intestine. So that means that there’s actually been damaged to the intestinal cells themselves. And that’s part of the celiac disease continuum where you take these villi, which are these plush, that’s like a shag carpet, and then all of those shags, the projections ended up being destroyed, and that’s through that transglutaminase process. So that’s the enzyme that’s in the intestine and that gets destroyed. So that I’ll use, as I said, for patients that I am more concerned about in terms of their gut stuff. And also, we know that celiac disease has issues all over the body, right? So, you know, usually, if they’re, you know, in childhood failure to thrive, diarrhea, abdominal pain, bloating, weight loss, etc., and then that goes on into adults with lesions, depression, thyroid issues, etc. So those are the criteria I use for doing that other test.

John: Fascinating stuff. And that segues nicely. There’s a ton of questions for you. One that I just thought of after you mentioning failure to thrive is…and in the literature you sent over the whole autism spectrum disorder was mentioned. What does the audience need to know about the link between food sensitivity and failure to thrive may be delayed verbal, some of these issues that can show up in children with either very severe or mild cases of autism.

Dr. Evans: Yeah. And we’re seeing, you know, more and more of that. And I would say that the two main mechanisms, the two main underlying mechanisms to think about are inflammation and toxicity. And one of the things that impairs or decreases the body’s ability to eliminate toxins is inflammation. So inflammation impacts, you know, brain or neurological health in two ways, direct damage to the brain mitochondria, its, you know, function as a neurotoxin, as well as impaired elimination of the toxins that impact the brain as well. So that’s why this test is so important.

John: As a physician with these types of patients you’re seeing all the time, what kind of turnarounds are you seeing with these children in terms of, if you could share a specific story, obviously, not giving any details that will give away the identity of the people. And then the second prong to that question is, so is this like…are you testing these kids and you’re finding that they’re deficient in glutathione or are you looking at some of these like superoxide dismutase markers, or how are you identifying, in addition to the fit test, that they have a decreased ability to get rid of sort of their toxic load on their own?

Dr. John: Sure. So these are great questions. So, you know, in my practice, you know, I definitely see kids on the spectrum, but I also see a greater number of kids with mood disorders, anxiety, or depression. That isn’t increasingly prevalent in the practice. And in those cases, elimination of food can create a change in symptoms in days to weeks. I mean, I’ve just been astounded. And for the kids that are on the spectrum, especially the ones that are more seriously affected, it’s a slower and longer period of time. Before we see results though, I just, you know, worked with somebody who actually came over from the UK and with multiple symptoms and was already seeing improvement after like three or four days. So I can’t tell you about the percentage of symptoms that are caused by food sensitivities in every patient, but I’ll tell you that it’s a slice of everybody’s pie, I just can’t tell you how big the slice is. So that’s why it’s such a good intervention, relatively inexpensive, is to avoid those foods that create inflammation. As to the specifics about evaluating the ability to clear toxins, that’s a genomic evaluation. So I do a test on detoxification genes so I can see about the cytochrome P450 system, I can see about methylation both with MTHFR and COMT, which are the two genes that are most important for methylation. I look at the, you know, the net genes, I look at gluthathione-S-transferase. So, you know, the acetylation gene, so all of the genes for detoxification need to be assessed. And then there are nutritional interventions for each of those different genes.

Now, I also measure levels of the main detoxification compounds. So I measure glutathione levels in all of these patients. I also measure oxidative stress, and so, I measure lipid peroxides. I measure 8-hydroxydeoxyguanosine. So I know if there’s actual DNA, intracellular DNA that has been damaged by free radicals or oxidative stress, because increased oxidative stress is another underlying pathway that causes the symptomatology. So you have to look at detoxification, inflammation, and then oxidative stress, especially, then looking at, are there toxic heavy metals because heavy metals are associated with these symptoms and people being on the spectrum. And then you have to be able to ensure adequate elimination of the heavy metals. So it’s a complex web, and you’re asking great questions, but basically, the principle is inflammation, detoxification, oxidative stress, and we measure about detoxification through the gene profile for oxidative stress, we measure the actual free radicals that we talked about. And then for inflammation, we’ll definitely assess, you know, CRP, I like the high sensitive CRP, and then the food inflammation test. And those are the three legs of the stool for kids on the spectrum or kids with mood disorders where we really find methylation as an important abnormality.

John: Yeah, that’s a very interesting panel. One of the things that I instantly think to ask more about when you mentioned cytochrome P450 is I’m sitting here… I had, you know, an espresso this morning prior to this interview as I do, you know, most mornings, but I’m a slow metabolizer of caffeine. I believe cytochrome, that marker is usually associated with caffeine metabolism. Is that right?

Dr. Evans: Well, again, we can really get into the weeds here. So cytochrome P450 is a general term for a large group of enzymes. So there are many, many cytochrome P450 enzymes, and those enzymes are coded for by different cytochrome P450 genes. But, for example, drugs go through the cytochrome P450 system. So we don’t say it’s a cytochrome P450 gene, we say the cytochrome P450 system, and in that system, there are different genes. So there’s 1A1, for example, with estrogen metabolism and, you know, 1A1, 1A2, 3A4 and 5. Then there’s so cyto, you know, 2CD6, which has to do with tamoxifen. Then there are cyto, you know, in grapefruit can actually change the way those enzymes work and can create issues with levels where people can become toxic or people cannot get enough of the medicine they need. So cytochrome P450, as I said, as a system, and caffeine is one of those substrates, meaning the compounds at the cytochrome P450 system acts on. And so, slow metabolizers of caffeine have the effects remain longer. So that’s why they’re more sensitive to it.

John: Okay. That’s a great clarification. That just parked me up there. I was like, “Okay, I shouldn’t ask about that.”

Dr. Evans: But let’s just talk about coffee for a bit because, you know, there is so many different interpretations, or I should say people answer the question, is coffee good or bad, in so many different ways, right? And what I would say in general is that one of the bigger negatives of coffee is that it’s very acidic and we always try to eat a more alkaline-based diet. So things that are acidic would be sugar, caffeine, and, you know, flesh foods, whether it be fish, you know, beef, chicken. So alkaline foods are fruits and vegetables. So ideally, 80%, and, you know, that’s a rough number, but 80% of your diet should be from the alkaline section. So when people go keto or paleo, and they’re eating, you know, they can be eating way too much animal protein and not enough vegetables, and that’ll drive their pH more acidic. We can balance our pH, but then you leech calcium from the bones, for example. So people that have joint pain, I often say just eliminate caffeine, you know, eliminate coffee and eat a little bit less of the animal protein, and their joints get better pretty quickly. From that perspective, you know, you don’t wanna have too much coffee, just keep the amount of acidic food to 20% or so. Having said that, coffee itself, actually, has a lot of positive qualities, and so I’m not against coffee. Someone who is a “slow metabolizer” or someone who we know has reaction, you know, sustained reaction to it just shouldn’t drink too much.

John: That’s for sure. Yeah.

Dr. Evans: That’s how I think about the whole coffee issue.

John: Yeah, that’s fascinating. What I find works really well for me is limiting caffeine intake. I mean, sometimes, I’ll kind of just blow that out and just have just kind of a caffeinated, you know, “more productive” day. I’ll pair it with CBD sometimes. But this whole issue of acidity is a really interesting little rabbit hole to go down. What I notice, you know, and some of the audience will get a little chuckle out of this, but I’ve seen some, I think, are fairly obscure studies that tend to show… I think there’s a small study in Japanese women that the acidity or alkalinity of the urine is actually something that can help you either excrete or hold onto more uric acid. So I’ve noticed that when I drink espresso, it’s actually very alkalizing on the pH of my urine because, you know, obviously, I don’t know of a way to test for the pH in the blood on, you know, sort of like N equals one sort of way. But just as an anecdote, it’s kind of interesting. I’ve seen that happen. What’s your take on alkalinity of the mouth and also of the urine?

Dr. Evans: You know, I would tell you that I’m not sure that that sort of area’s ready for prime time yet. I think that the best way to ensure what’s going on with your internal pH is to ensure what’s going on with the relative alkalinity or acidity of your diet. So there are some good, you know, there are some… Actually, there’s a very good paper that has to do with diet and cancer, for example, talking about how cancer cells prefer an acid environment and that an alkaline diet is really important. But there’s no…I don’t think a really good way to check. And I think that what you’re talking about is scratching the surface. But as I said, it’s not ready for prime time.

John: Oh, 100% concede that. When I’ve mentioned that to Aaron who’s our head of research, he just like, “Dude, just… No, we’re not even… We’re not even talking about that.” But I just throw it in there because it came up. And I think it’s interesting that, you know, I notice the acidity with the flush foods you’re talking about for sure, but for whatever reason, with espresso, it seems to be in that way… Whatever that’s worth, it’s probably worth very little, but just anecdotally, just throwing that out there. Another thing I wanted to ask you was, you know, on your test, and then in the stuff you sent over, there’s this interesting kind of range of these IgG markers. You have like IgG1 through 4. And IGG1, and correct me if I’m wrong, but I believe it was stated that that is the antibody that reacts to like a new food. And I thought, you know, “I wanna ask Dr. Evans what he thinks about this issue of epigenetics.” Because I hear you also on this whole acidity and limiting animal protein thing. It sounds like maybe that’s also like a Valter Longo. I don’t know if you’re a fan of Valter Longo or not.

Dr. Evans: I am.

John: He’s great. A lot of people love him. I think he’s super smart. But it comes back to, are we just having this situation where the patients that you’re seeing are the people who, you know, going back… Because Valter Longo talks about this and, you know, he’s a very credible scientist and it’s in his book, “The Longevity Diet,” this whole idea of, okay, so going back five, six, seven generations, me coming from Irish heritage, my ancestors would not have eaten banana. So, therefore, I’m putting banana in my system. You know, I may have eaten it as a kid, but it’s not in the wheelhouse of my epigenetics. And so, that is, therefore, triggering IgG1 as a new antigen and then that sets off a cascade of food sensitivity. What say you about the whole eating for epigenetics issue and how that could tie into your test?

Dr. Evans: Well, what I would say is I look at that theory as one that got some validity to it, and the way I sort of work through that with my patients is, number one, what’s the degree of, you know, sameness of genetic heritage compared to your ancestors? Because a lot of people change, and move, and intermarry, and so on. And so, then there’s a lot of sort of differences in genetic makeup, which means, though, seven generations ago, you might have been, you know, in Ireland, seven generations later, there’s a lot of different genetic influences in your DNA. And so, that’s important, as well as where you’ve lived. So if you are living in Ireland and have been in Ireland for 7, 10 generations, then you’re better off eating a local diet. So most people do better eating a diet that’s local to them. But because of the differences in heritage, it’s difficult to define what local is. So having said that, I think it’s hard to say that you can only eat, you know, what your ancestors seven generations ago ate because the gene pool’s a little bit different. And that’s where this test can come in because it can identify those foods that you shouldn’t be eating.

Now, what do you do about sort of this general statement, I mean, that people are best eating, you know, what’s local? Yeah. At the same time, does that mean if you’re inland you shouldn’t have fish? I don’t think so. Does that mean if you’re in a Northern climate you shouldn’t have avocado? I don’t think so. If you’re sensitive to some of those foods, yes. But I think that a varied, you know, whole food, healthy diet, low on sugar, you know, minimal alcohol is the way for most people to eat. And then if you’ve got GI symptoms and illness of family predisposition to cancer or Alzheimer’s, then you have to be really sure to make sure there’s no inflammation being driven by what you eat, and then you do the fit test. And that’s how I answer that question about genetic issues and cultural issues in foods.

John: Yeah, that’s a great answer, because how could you really tell us? It’s out there. People are talking about, that’s why I wanted to ask you. Well, and another thing is hydrochloric acid level, because you talk about basically these large food particles are making their way where they don’t belong and the immune is reacting. And I think I’ve read that you’ve said that that could be an issue with hydrochloric acid. Do you have tips for people at home to increase their hydrochloric acid levels and improve digestion?

Dr. Evans: Well, so first, let me just expand on that hydrochloric acid thing because, you know, that’s an example where it’s not the food that causes the food sensitivity, right? It’s the low hydrochloric acid, and the reason we need to have a very acid stomach is because the acid environment is how the enzymes that digest the food work. And so, if you don’t have the ability to digest your enzymes, I mean, to digest your food because your enzymes aren’t working properly, then you’re going to have food sensitivities. So it’s the acid and we know that people that have low stomach acid have more food sensitivity, and that leads to more leaky gut as well. So it’s really important to have that amount of acid in your stomach. So the classic things that we do, you know, to increase acid, you know, chew your food well because that will help produce stomach acid. Try to decrease stress. You know, sometimes, you know, calcium is important because calcium can help keep that upper sphincter, that…or the lower esophageal sphincter or the upper gastric sphincter closed so that the food stays longer in the stomach and you don’t have reflux. So that gives you more time for the food to work. And then there’s…what I do is I give stomach acid. And so, what I do is I give a sort of betaine HCL product and we just give it until we see if there’s burning. And if there’s burning, then we know that stomach acid is adequate, and then you slowly, slowly decrease it, and then you repeat that process every, you know, four months, two or three times a year just to make sure you have enough stomach acid.

John: So if you take the stomach acid and it causes you immediate burning or discomfort, you have enough stomach acid.

Dr. Evans: Correct. That’s the immediate test. Now, I don’t do that test on everybody, but I do that test when I see patients that have a lot of food sensitivities because that low stomach acid is one of the triggers of food sensitivity that I have to investigate it.

John: And what other supplements do you see that work well in your practice for healing the gut?

Dr. Evans: Well, you know, I happen to like this compound called SBI Protect, which is a direct anti-inflammatory compound. I like any kind of prebiotics. I use something, you know, called Endefen, it’s very good. I like glutamine, which is very important. I like colostrum, a good probiotic. Those are, you know, the important things. And, you know, we can always talk about different, you know, supplement companies, but I don’t know if that’s really appropriate for this right now.

John: No, I hear you. Okay. So in closing, people are interested in the test. How can they find the test? Can you buy it on Amazon? Do you need to be working with a physician? Like, how can people go?

Dr. Evans: Yeah, I think start with

John: You can order the test from that website?

Dr. Evans: Well, what they will do is they’ll talk to you about different options. And I know that we are in the process of developing, you know, different ways for patients to have access to this testing. So I’m not sure right now what they’re doing for what I would call direct to consumer product. I don’t know if they’re trying to do that, but for now, what I would suggest is call the lab or email the lab, and they will then be able to direct you the best way to get the tests done.

John: Very cool. And for people that wanna learn more about you, are you on Twitter or Instagram? What’s your website? How can people…?

Dr. Evans: You know, I got to tell you, it’s the CFFM for the, and I’m sure I have an Instagram and Facebook, but I got to tell you, I am a social media dinosaur, but definitely, there is an Instagram account for me. There is Facebook for both the practice, and I have a professional Facebook, so you can definitely get me there.

John: That’s awesome. Thank you so much for taking the time, Dr. Evans. It was a lot of fun. Got a lot fitted into that hour-long conversation.

Dr. Evans: Oh, we did. You’re a great interviewer.

John: We touched on a lot of stuff.

Dr. Evans: Great interviewer.

John: Thank you so much for your…

Dr. Evans: Thank you.

John: …for your time, and we’ll be in touch. Thanks.

Dr. Evans: Okay, good. Yeah. Bye-bye.

John: The “Gene Food” podcast is our attempt to synthesize the latest developments in the fields of genetics, nutrition, and medicine, and offer you practical tips and stories you can use in your own unique health journey. If you enjoyed this podcast, you can find more information online at

John O'Connor

John O'Connor is the founder of Gene Food, a nutrigenomic startup helping people all over the world personalize nutrition. John is the host of the Gene Food Podcast and a health coach trained at Duke's Integrative Medicine Program. Read his full bio here.

The very latest on genetics, nutrition and supplements delivered to your inbox!


Leave Comment

  1. Marion says:

    Thank you SO MUCH for this podcast. I’m looking into ordering the FIT test through a nutritionist in Massachusetts and I’m really excited to work on some of these food sensitivities I’ve had for years now.. migraines, etc. This was super helpful! keep up the great work.

  2. MartyE says:

    Great show with a lot of new information I had not heard before. Please consider providing transcripts of your shows.

Leave a Reply

Facebook icon Twitter icon Instagram icon Pinterest icon Google+ icon YouTube icon LinkedIn icon Contact icon Info icon