Thiamine Deficiency & High-Calorie Malnutrition: Could Hidden Nutrient Deficiencies Be Why You’re Still Sick? | E189
23 Oct 2026 · 13 min
In this solo podcast episode Dr. Aaron Hartman discusses the widespread problem of high‑calorie malnutrition in the United States, highlighting that 40‑60% of Americans lack at least one B vitamin and many have sub‑optimal magnesium, potassium, and vitamin D levels. He explains how thiamine (vitamin B1) deficiency—both absolute and functional—can manifest as wet or dry beriberi, dysautonomia, POTS, chronic fatigue, and mitochondrial dysfunction. Drawing on his clinical experience, he notes frequent undetectable B1 levels in patients and describes his use of IV vitamin C protocols that include a full suite of B vitamins, magnesium, calcium, and thiamine. He shares anecdotal evidence of high‑dose thiamine (1‑3 g/day) improving tremors in Parkinson’s patients. Dr. Hartman proposes a practical “back‑to‑school” supplement regimen—active‑form multivitamin, quercetin/nettles, and NAC/acetylcysteine—to address hidden micronutrient gaps. He contextualizes the issue historically, referencing fortification of bread and past beriberi outbreaks linked to processed foods, and explains how modern high‑calorie, low‑nutrient diets strain metabolic pathways (Krebs cycle) that require B vitamins. The episode concludes with encouragement for patients to seek testing, work with knowledgeable clinicians, and remain hopeful about healing potential.
Chapters
Are we dealing with an epidemic of high-calorie malnutrition? I think the answer is yes to that. If you look at anywhere from 40 to 60% of Americans, 40 to 60% of Americans will have any single B vitamin deficiency. If you look at, depending on what you read, maybe 80% of Americans have a suboptimal magnesium level. Maybe up to 100% of Americans don't have adequate potassium. That's crazy. Why are you still sick? Why are you stuck? Why is your body not healing? Why, even though you've Been treating your Lyme and your mold and your MCAS and all these other things. You're still stuck. You're not getting better. You got a little better, maybe, maybe not some better days. Maybe over the last year, your trajectory is up, but you're not making the progress you'd like to be making. What's another reason why you might be stuck? I want to talk about something that I learned actually while reading Toxic, which is one of Neil Nathan's books. And then in the stuff with him, it was interesting. It's really interesting. Like I go to these conferences, I get these training courses under individuals and they're like, yeah, read this book and you buy the book and you read it and you're like, oh my gosh, my world was changed. In one of these books, it's a long title, it's called Thiamine Deficiency, Dysautonomia, and High-Calorie Malnutrition by Dr. Launders, who was a pediatrician at the Cleveland Clinic. The basic premise is this: thiamine deficiency can be a cause for wet or dry beriberi, which is basically neurologic thiamine deficiency and cardiac. So, what can that look like? That can look like POTS, that can look like dysautonomia, that can look like chronic fatigue. All of a sudden, all these things I've been talking about are Over all these ten-minute series could be related to a thiamine deficiency. Now, there's absolute thiamine deficiency, which we described like wet and dry beriberi are the severe versions of that. And there's a functional thiamine deficiency where your level is low normal. And to be honest with you, in my clinic, I routinely check this on patients, and I'll have people who have undetectable thiamine levels. And I'm like, why is it happens way too often? To be honest with you, probably every month I'm finding someone with an undetectable B one level, and it's like whoa. I need to fix this level, but this can set you up for dysautonomia, particularly in kids, particularly with chronic fatigue, fibro, particularly with mitochondria. Here's a big word: mitochondrial issues. How many of you heard about mitochondrial issues, mitochondrial deficiency, etc., etc.? I've been doing IV vitamin C therapy in my clinic for years, and I'm into hypermobility as many when so patients come in. Let's give you some IV vitamin C, and oh my gosh! You're doing so much better with your vitamin C. It's really funny because I initially used to think, ah. So vitamin C, vitamin C is an antioxidant. Vitamin C is, oh, it's, it's an antiviral. It helps with connective tissue with hypermobility. What I learned is the way I do it in my office, we also do 100 milligrams of thiamine and some other things. And I started having to rethink that as I realized maybe I'm treating this functional thiamine deficiency that's resulting in dysautonomia in my patients. And so I've started using thiamine therapy by itself. You start and you go off these weird, you go down these weird rabbit trails. There was actually an Italian researcher who was using high-dose thiamine. I'm talking about 1,000 to 3,000 milligrams a day in Parkinson's patients. And I've got a couple Parkinson's patients who've done that, and it's actually been— had one in particular, it's actually had a significant impact on her tremors. So you have to ask yourself, wow, that's thiamine. That's— what's the safe level? And the answer is, again, talk with your doctor. This podcast for educational purposes only, but you can— it's pretty up. You can take a couple thousand milligrams and it's safe. Again, talk with your doctor. Not recommending that. It's just in the literature. There's a book about it. Every fall, the schedule tightens and most of our attention goes to getting the kids ready. Almost none of it goes to the person holding the whole thing together. So I put together these 3 things just for that: a daily multivitamin in the active forms your body can actually use, quercetin and nettles to support your immune and respiratory health without the drowsiness, and NAC and acetylcysteine to help your body rebuild its own antioxidant reserve. This is what I take every fall. That's aaronhartmanmd.com/backtoschool. Point being is all of a sudden, if you're not getting better, could you have a functional nutrient deficiency, thiamine being one of them? But this other concept that got opened up to me is the whole idea of high-calorie malnutrition, which I was like, yes and yes. So what is this concept of high-calorie malnutrition? When you start looking at the malnutrition literature, Thiamine deficiency, riboflavin, pyridoxine, folic acid, B12. You start seeing weird neurological issues, skin things with niacin. You get weird rashes like really horrible eczema, psychiatric issues, POTS dysautonomia, neuropathy. How many of those do I see? And, I see this stuff all the time with my POTS dysautonomia, mold, Lyme, whatever, long COVID, concussion patients. How many of these people— this is interesting, maybe I'll change this to not just thiamine. How many of these people are dealing with And I don't know what to call this because it's a book about it. I'm looking at right there on my— where is it? Right there. Yeah, it's sitting right there. It talks about this. This— I'm not sure when it came out, but if you're interested, you can look up the book, Thyroid Deficiency, Dysautonomia, and High-Calorie Malnutrition. And Dr. Londa, L-O-N-D-A-L-E, and Mars, M-A-R-S. My vision's not the best, so that's— but look it up. The gist though is this, that probably a lot of my patients— and we do lab testing and do functional testing, organic acid testing— you start seeing all these people With low-level or absolute nutrient deficiencies, you're like, why aren't you— like, you're healthy, but you're seeing me for all these other issues. Are we dealing with an epidemic of high-calorie malnutrition? I think the answer is yes to that. If you look at anywhere from 40 to 60% of Americans will have any single B vitamin deficiency. If you look at, depending on what you read, maybe 80% of Americans have a suboptimal Magnesium level. Maybe up to 100% of Americans don't have adequate potassium. That's crazy. Vitamin D. How many people— all my patients have low vitamin D levels. And that nationwide numbers are like 40 to 60%, but I think it's higher than that. But sometimes the literature and data lag clinical experience by sometimes a couple of decades. So it's really interesting how things I've been talking about for years, sometimes they pop up in the literature decades later and you're like, oh, look at that. I guess I was right. Like the peanut allergy or the hormones or fats back, right? It took us some 50 years to figure out fat's good for us, right? Or hormone replacement therapy, it's back, right? So this is a phenomenon that happens pretty often. But the idea is that developing low-level of these things from what? From high-calorie malnutrition. What is that? Processed foods. The source of these nutrients actually are the foods themselves. Now we're going back to gut stress, sleep, gut, food, real food, right? It's interesting. In 1940, I think it was, fortification of bread became mandatory by the government. Because people were getting nerve damage from eating processed grain. That's the reason why your bread's fortified now instead of just using whole grain, real whole grain, not fake whole grain. We just put some folic acid and riboflavin in there and call it a day, right? There was actually in France in 1900, they banned corn for a time because mothers were having kids with cretinism by nutrient deficiency driven by consuming corn. That's interesting. But the idea of high calorie malnutrition, if you eat lots of calories, carbs, sugar, basically in the form of carbohydrate molecules that come together that your body turns into sugar, it requires nutrients, minerals, manganese, selenium. It requires certain B vitamins to process and make energy. If you look at the, the citric acid cycle, for example, also called the Krebs cycle, you'll see all these vitamins in there, right? And in my world, we actually put things in to actually speed up energy production. If those levels are low, what's that going on? What's that? How's that going to affect energy production? It's going to be less. And so all of a sudden you're eating foods that require these minerals, vitamins, and nutrients to process the food. The foods are deficient in them and you actually drive high thiamine malnutrition. The book Dr. Launders, you know, it was really interesting. One of the stories he talked about in there, which I remembered because we talked about in medical school, was Japanese in Japan, late 1800s, early 1900s, getting basically wet and/or dry beriberi. And what happened was you'd eat rice, which didn't have thiamine. And if they got sun exposure, they drive a skin version of this deficiency in them, or they work a really hard day and get heart failure, right? They get the cardiac, the wet beriberi. Very extreme example. We don't, as far as I know, that's not happening anymore in the world. But the point is there's a low-level subclinical grade that's being driven by us eating processed foods. I started with this by talking about thiamine deficiency, and you can replace that, you can do thiamine shots. But what about all the other nutrient deficiencies we get low-level That increase your risk for these other weird neurological issues, high-calorie malnutrition. How prevalent is that? Every fall, the schedule tightens and most of our attention goes to getting the kids ready. Almost none of it goes to the person holding the whole thing together. So I put together these 3 things just for that: a daily multivitamin in the active forms your body can actually use, quercetin and nettles to support your immune and respiratory health without the drowsiness, And NAC and acetylcysteine to help your body rebuild its own antioxidant reserve. This is what I take every fall. That's Aaron Hartman MD dot com slash back to school. I do know that I test a lot of patients for nutrient deficiencies, and a lot of them are deficient in a lot of stuff. Then the question is maybe that's the reason why my IV vitamin C we do in our clinic helps so many people. They feel so much better with it. Oh, what do I put my IV vitamin C? I just do what the people I trained under trained me to do. I tend to five. I'm not the smartest guy in the room. I tend to try to find those people and train under them. And just basically, I call myself a leech. I find really smart people, attach to them, and suck the blood, learn their knowledge, process it. And that's what a good teacher wants. A good teacher wants their pupil or their student hopefully to be as good or better than them. That's what parents are for their kids, right? And so, incorporate this stuff. And, vitamin C, I do. It's vitamin C, it's magnesium, usually mag sulfate, it's calcium, it's B1, B2, B3, B5, B6, B9, That's like the standard IV we do. It has all those in there. And so, now the question is, why is— maybe so many of my patients feel better on IV vitamin C because they're getting all this other stuff. Maybe that's the reason why when they go to the local area and get the Cs at the wellness clinics or spas and they only do vitamin C only at low safe doses, which is another misnomer because you can do— if you don't have a G6PD deficiency, you can do 50 grams of vitamin C without any problems. If you do it slow and you balance the pH with the right— Yeah. With all the right things, which the devil's in the details with all this stuff. Point being is like maybe that's one of the reasons why people get better with just basically given— how many people, I started my B complex, I started my multivitamin, I did this really high quality thing, I feel better. Maybe, just maybe, part of these— you're stuck, you're not getting better. Yes, the B1 is the specific one for the dysautonomia, thiamine, high calorie malnutrition, but maybe bleeds out into more things. Maybe Mass, high-calorie malnutrition, micronutrient deficiencies. And now we're coming back around the gut. Eat real food. But sometimes that's not enough. Sometimes you have to— if your whole body is deficient in omega-3s, if your whole body is deficient in D. I've had patients, I had one patient, I was looking at their labs with them during the pandemic, their vitamin D. I'd started testing it in 2012 and it normalized in 2019. So it took 7 years for it to get into the 60 to 80 range. Sometimes it can take a while to get the levels up. Depending on what the nutrient is and based on what your nutritional status is. If you're not, if you're stuck, you're not getting better. Why are you stuck? Maybe you just haven't had the right nutrient stuff done and you need to fix those things. Thiamine can be helpful. B12 can be helpful. I have some patients that with B12 and thiamine shots, they feel great. It's relatively inexpensive. There's so many things out there. I'm not going to go through all the things that might be the reason why you're still sick and stuck, but hopefully as we walk through this, it helps you start thinking. One, can I address these? Two, who can I work with to help me with this? And three, you, there's hope. There's answers. There's things you can do to help you get better. And that's the big picture is that there's always something. I, this routinely, I will, I'll learn something new. I have someone come in the clinic a week or 2 or 3 later that I literally just learned the thing they need weeks prior. There's always hope. There's always new things. Never give up on yourself. Keep on going. You were made to heal. You were made to self, your body was made to self-heal and self-repair. Just lean into it. There are answers out there and you can, no matter where you're at in your healing journey, as long as you're alive, your body has healing potential. Don't know how much that is, but you should always lean into that. Anyway, take care. We'll talk to you soon. You came here for straight answers on your health. No hype and no gimmicks. We work hard to give you that on every single episode. So if you could do me a favor, that would be amazing. Leave a quick review on Apple, Spotify, or wherever you get your podcasts. It just takes 30 seconds and that'll help other people find the same information you found helpful. Thank you so much.
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