Speaker 1:

Welcome to AACE Podcasts. Thanks for tuning in as we elevate clinical endocrinology by taking deep dives into trends and topics that can help us improve our patient care and global health. Find the latest episodes on aace.com/podcasts. And now let's meet the endocrine experts who will be talking with us today.

Dr. Tabatabai:

Hello everyone and thank you for joining us for this ACE podcast on bone health optimization with food and fitness. My name is Dr. Layla Tabba. I am the chairman of the Bone and Parathyroid Disease State Network for ACE this year, and I'm very honored to be joined by two amazing experts today, Dr. Deborah Sellmeyer from Stanford and Rebecca Rothstein of Buff Bones, and I'd like to introduce both of them in a little more detail. Dr. Sellmeyer is an internationally recognized expert in metabolic bone disease. She's a renowned endocrinologist who joined the Stanford faculty in 2018 as a professor of medicine. She's been recognized for clinical excellence with induction into the Miller Colson Academy of Clinical Excellence at Johns Hopkins. In addition to her clinical expertise, Dr. Sellmeyer maintains a research program centering on the effect of nutrition and environmental factors on skeletal metabolism studies. She has conducted include investigating the role of dietary sodium chloride, dietary protein, role of dietary potassium and alkaline salts, targeted exercises on kyphosis, whether structured exercise can prevent bone loss in premenopausal women with breast cancer and studies validating nutritional assessment questionnaires.

I'm very honored to have been Dr. Sellmeye fellow during my endocrinology training at Johns Hopkins and our other expert today. Rebecca Rothstein is the founder of the Buff Bones Exercise Method for Bone and Joint Health with online programming and coaching free public education webinars with UCLA health and training for instructors in more than 30 countries as well as locations including Johns Hopkins Rehabilitation Network. Rebecca is an industry leader for movement education, bone health and Pilates for more than 20 years with a background in dance and sports medicine. She serves on the Ambassador Leadership Council for the Bone Health and Osteoporosis Foundation on the Medical Advisory Committee for the National Menopause Foundation, bone Health Working Group for the Society for Women's Health Research. And in 2024, Rebecca was awarded the Robert Gale MD Community Leadership Award from the Bone Health and Osteoporosis Foundation. So truly honored to be joined here by both of you. And I'd like to get into some questions so we can have a conversation on food and fitness and how it ties back to osteoporosis. So first all for you Dr. Sellmeye, can you talk about the calcium controversy? I think a lot of us have patients who've been told to stop all over their calcium because of the risks of coronary or renal calcification. So how much calcium do osteoporosis patients really need and how are they supposed to get it? What would you recommend?

Dr. Sellmeyer:

So the calcium issue became very controversial more than a decade ago when there was a single study looking at an intervention of calcium citrate a thousand milligrams per day. And among those randomized to the calcium citrate group, there was a higher rate of self-reported myocardial infarctions. So this raised quite a bit of concern, but actually within that study, if the events adjudicated and non-recorded events were included, there actually was no difference even within that initial study. However, the concern raised by that study, and it was published a couple of times in various different ways, really alarmed providers and patients as well in terms of what was safe in terms of calcium. And so there were a few studies that kind of rebutted that, but I think the definitive examination of this issue came with publications one in 20 16, 1 in 2017, which were massive literature reviews, consensus conferences among four international societies, bone and marrow societies and cardiology societies.

And there were two separate analyses at both concluded there was absolutely no concern for vascular calcifications, mild Carly infarctions vascular disease among people taking recommended amounts of calcium either through diet or through supplements. So I think that issue has largely been laid to rest, but it still is a pervasive concern among our patients. And so I think we can use that data to reassure them that at the amount of calcium that we recommend for bone health, there is no concern about heart disease or strokes. So recommended intakes for adults are a thousand milligrams per day up to age 50 and then 1200 milligrams per day after age 50. For women. For men it goes up to 1200 milligrams after age 70, so roughly 1200 milligrams in the older population. And that is total, that includes both food and any supplements. And I think the piece people often forget is that your baseline diet, even with no calcium rich food has a small amount of calcium. So there's about two 50 to 300 milligrams of calcium and just our general diet. So really people only need to identify about another 900 milligrams of calcium in their day. The intestinal calcium from dairy foods, fortified foods and from supplements is exactly the same. So people can get their calcium from any combination of sources that works well for them.

Dr. Tabatabai:

Excellent. That's definitely for our patients who I think get a lot of information from well-publicized studies that don't necessarily reflect what we know now. So that's really useful information. Yeah. Now Rebecca, can you tell us about weightbearing exercise? How does this help prevent bone loss and is weightbearing and resistance exercise the same thing?

Rebekah Rotstein:

So this really comes down to mechanical stimulus and wolf's law that bone has this adaptive response to stress and specifically really compression and tension forces. When we're talking about weight bearing activities, we're talking about getting the compression from gravity. And then interestingly though, weight bearing is not necessarily including resistance. So resistance resistance exercises are a completely different thing and that is where you're getting the tensile pull from muscle contractions and it's using progressive overload. So that's what the challenge is knowing that bone has this adaptive response, you have to continuously increase the challenge, whether it's through additional load, through other forms of volume with repetitions and sets. But we have to consider how load plus gravity is really the key to a lot of resistance training and that's often the secret to success. So it's interesting you have this mechanical side that is kind of unique, especially when we're talking about medication or nutrition and these types of interventions for bone health. The unique side of exercise is the mechanical stimulus, but there's also potentially a chemical side with that which is that are released from muscle contraction might actually be at play as well in bone metabolism. So muscle really does warrant a lot more investigation in this.

Dr. Tabatabai:

Fantastic, that's really good to know. I think we all recognize that exercise appears to stimulate osteoblast activity and potentially help reduce osteoclast, so potentially less bone loss, more bone formation. And the role of mykines is really fascinating there. So there's probably even more at play than we know, but clearly people, patients who are just completely bedbound or very, very sedentary clearly have risk for bone loss and that can be mitigated a good deal with osteoporosis exercise. What types of exercise do you believe to be the most effective for osteoporosis?

Rebekah Rotstein:

Well, we're talking about effective, right? Just like with medication, your primary goal with exercise is going to be fracture prevention. So where things pointed toward, especially in the last decade, is about a multimodal approach. There's not one type. This was really highlighted in the 2014 paper to fit to fracture out of Canada, which was also then updated about two years ago along with consensus papers in Australia and the UK really we're seeing three different things and weightbearing that we were talking about is a given pretty much with all of these resistance training. And that's the one that really needs to be prioritized has come up to the forefront specifically when we're looking at osteogenic effects. And there needs to be not only the challenge and the progressive element to that, but also including functional movements. So things that mimic daily activities, pushing, pulling, squatting, those types of things.

Compound exercises like multi-joint exercises, also an emphasis on axial loading and then specifically especially if we're dealing with people with hyper kyphosis, getting into back strengthening and back extensor strength. Then the second type is impact training. The quality of evidence is actually a little bit less than it is for the resistance training, but it is still recommended as one of the three most important things that needs to be included. It does have to be accounted for individual risk, but we're looking at ground reaction forces with the impact starting off with something like heel drops. So it's low impact and progressing to higher impact as appropriate for the individual. But looking at ground reaction forces that are at least twice the body weight are probably what are needed for bone mineral density changes like in the femoral neck. And then the third aspect is balance training, which is not osteogenic but is critical for fall prevention and therefore fracture prevention.

And that can include things like tai chi, Pilates, yoga benefits here as well and often includes some mobility in these aspects. But it's important to note too that strength training also can have a carryover effect with balance as well. And then two things that are not yet considered the major three but also do have value and have been pointed out in guidelines is power and posture. Power train is really interesting because, so strength is the amount of force your muscles can generate. Power is how quickly they can do it. So power training has really emerged with some research as possibly even more important than strength training for bone density and for function. And then posture also relates to fall prevention, especially useful for kyphosis, very important with neuromuscular control. So essentially these are the main things that we have to focus on when we're looking at different types of exercise.

But also we have to account for the fact that especially when we're thinking of the osteogenic side, that the exercise has to be site specific so the bone adaptations are going to occur wherever we have that direct mechanical stimulus. So really being the hip, the spine and the wrist, and it has to be very specific to the individual and that's one of the things that's really it is really emerged especially in the guidelines as well, that research often uses healthy individuals, but that's not always representative of many people and the general public. So we have to be specific to the individual needs with any kind of exercise programming.

Dr. Tabatabai:

That is fascinating and thank you so much for explaining that in such great detail. I think oftentimes as endocrinologists and clinicians, this isn't really our language. We are much more familiar with potentially medications, other types of therapies we can offer for our patients, but being comfortable speaking about exercise and potentially adapting that kind of program for our patients is critical. We need to hear from more experts like you, Rebecca, I think, so we can get comfortable with it. So Dr. Sellmeye, we spoke a little bit about calcium. Now switching gears just over to vitamin D. So excessively high levels is actually over 80 to a hundred nanograms per milliliter became quite common during the COVID-19 pandemic. And other patients such as those with multiple sclerosis or even colon cancer have been advised to have high vitamin D levels now for many years. Do you know of any downsides to hyper vitam osis D and what range do you aim for in your osteoporosis patients?

Dr. Sellmeyer:

We have seen both quite bit of interest in having higher vitamin D levels for other disease states outside of the skeleton, and there really is very limited evidence that there's any benefit to those higher levels both for the skeleton and for other disease states. And for sure there is an increased risk of nephrolithiasis. So when we did higher vitamin D levels, lower high calcium intake, our first defense is to start stopping calcium from the kidney. And so nephrolithiasis and hypercalcemia are our first indications that somebody is overloaded. And in the women's health initiative calcium of vitamin D study, there was a higher rate of nephrolithiasis and so those were even crazy amounts of supplements and women will start getting hyper calic with calcium, it takes over about 15 or 1600 milligrams. So there's a pretty narrow therapeutic window for calcium. And high vitamin D will also cause that same issue right now sort of aiming for, sorry for vitamin D levels between about 35 and 50 mammograms per ml.

The level of vitamin D also has been a controversy and I think that it's what really helps people understand that controversy with the institute of Medicine recommending levels over 20, most of the professional societies recommending levels over 30 is to understand that the institute of medicine is setting a very specific term. There's setting RDAs, recommended diarrhea allowances, and the definition of RDA is the average daily intake of a nutrient that is sufficient for 97.5% of healthy individuals. So first of all, they're not aiming to cover everybody that is outside the definition. They're only aiming to cover a large percentage of the population and it's specifically targeted for healthy individuals. So there isn't an exact definition of a healthy individual, but certainly people with skeletal fragility, low bone density, I'm not sure that we would count them in the same group as kind of the healthy general population.

So looking at the majority of the data, having a level over 20 does look like it's probably fine for the vast majority of people, but there are a lot of studies that show that there's still secondary. He parathyroidism, they're still under mineralized bone in a subset of folks with vitamin D levels between 20 and 30 nanograms per ml. So we really want to cover everybody including people with skeletal compromise. We need to get over 30 nanograms per ml and even the most staunch defenders of the 20 nanogram per ML value, we'll admit there really isn't any downside to having levels between 30 and 50. So I think that's what I generally target. Somewhere between 30 and 50, there is seasonal variability in vitamin D levels. There's also assay variability, especially at the lower end. So I try not to have patients levels clinging to the very bottom of that 30 because there's just going to be some variability. They're going to be down in the twenties at some point. So that's why I say sort of 35 to 50, I don't think there's any benefit to getting over 50 and you are going to start contributing to hyper cal. I think that's plenty and I don't see any reason to go any higher.

Dr. Tabatabai:

Fantastic. And what is your thought about using D three cholic calciferol versus D two or ergocalciferol?

Dr. Sellmeyer:

Yeah, D two and D three have the same binding affinity for the vitamin D receptor. So in terms of physiologic effects, they're the same. D two is cleared faster, and so if people get a single dose of 50,000 units of D two and D three, the D two is going to be gone faster than the D three. It's pretty much gone within two weeks. And so that breeds up another issue with vitamin D, which is what about these high dose intermittent regimens and then quite a number of studies looking at high dose regimens hundred thousand units a month or either 500,000 units once a year. And those data are a bit concerning in most of those. There's either been no effect or an adverse effect from the high dose intermittent vitamin D. So I would recommend against that. And we still use the 50,000 unit ergo cal serol to replete people quickly who have very low vitamin D levels and I think that's fine, but I am getting more and more away from using it as kind of a long-term maintenance supplement and I'm getting people onto the standard one or 2000 unit daily doses instead.

I don't know what the physiology is of that high dose intermittent vitamin D. There's some animal data that suggests there may be some negative feedback on conversion of 25 D to 1 25 D. So maybe people are kind of functionally vitamin D deficient with those super high doses, but we don't know for sure, but it's kind of been a surprisingly consistent amount of data now that that intermittent high dose super high dose vitamin D is not beneficial and actually may be harmful.

Dr. Tabatabai:

Right. That's really important to know, especially with patients wanting clear guidelines on what to take and exactly how much to take. So Rebecca, you introduced us to be various sort of functions and types of exercise that are beneficial for the bone. Can you speak to how often and how long should someone with osteoporosis exercise each week?

Rebekah Rotstein:

So the first thing is to point out the importance of consistency. So if you do it once and then you don't continue, it's not going to make much of a difference. So this is something that is essentially needing to be part of your lifestyle, that it's not just you're doing it for a short period of time duration and for the rest of your life essentially considering it almost like another activity that you would do of brushing your teeth. You're not just going to do that for two weeks and then forget about it. So taking, let's say that consistency is already taken for granted. Now when we look at frequency and intensity, the research hasn't been able to exactly determine a lot, but guidelines really have, so specifically with resistance training, you should be doing it at least twice a week with impact several times a week.

And then balance, they say that challenging exercises or tasks should be done several times a week, but really you can incorporate this into your life daily. When you're brushing your teeth, you can be standing on one leg. The biggest thing though is to stratify the risk count for the individual goals. Now what gets really interesting though when we look at the research is this discussion of intensity because traditionally it's always been thought that people with osteoporosis might be more fragile, more frail, and some of this has been changing. So when we talk about intensity, this is, and when we're specifically referring to resistance training, intensity has been measured in something called one rep max, and this also relates to the number of repetitions, but essentially where it's probably that moderate to high is the best for osteogenic effects and has the best potential to improve bone density after menopause with osteoporosis.

So the strain and the magnitude of the strain is what really may be important. So things changed in 2018, a study called the Lift More was published and it was unique in that it was looking at osteoporotic or low bone density subjects who were specifically post-menopausal women using a supervised version of high intensity progressive resistance training and impact training. And it showed it as safe, whereas commonly this had been considered risky, it had statistically significant improvements over eight months with around a hundred subjects we're talking lumbar spine gains of 2.9% femoral neck of 0.3%. They used the same protocol again a few years later in something called the MEDEX trial, both with and without antiresorptive medications that time. And I should mention that buff bones was included in that as the control, but I wasn't aware that this was underway, so I have no involvement.

But again, when they did this with the high intensity, there were again lumbar spine improvements and it was to a lesser degree though, and this time there were no femoral neck increases, but it seems that the spine has better bone density effects from exercise than the hip. So that's one of the interesting takeaways because again, this is the big question. It's not just how frequently should I do it, but what intensity, this has been the big discussion that's going on for a while and yet a meta-analysis in 2020 that was looking at exercise and bone density and post-menopausal women, that was really impressive because it had a hundred studies in it. It showed improvements in low, moderate and high intensity for bone density, but it pointed toward the high having the greatest gains. There weren't that many studies though. That's really the biggest takeaway right here.

In addition to a new meta-analysis actually that just came out last month, pointing toward aerobic exercise and resistance training combo having the best outcomes for bone density increase, but they weren't looking specifically at osteoporosis. So the big takeaway I would say for all of this is not only is there more research that's needed, but we need more research that's going to look at moderate to high intensity to really be able to determine what dosage essentially. And then also there's a lack of quality research here to really make conclusive statements specifically because a lot of the meta-analyses, I mean there's not that much research, but the ones that there are and with meta-analyses are not necessarily including or not having subjects that are with osteoporosis. And that's important because while we want to look at bone density gains and often with postmenopausal women, we do see from other meta-analyses that those with low bone density or osteoporosis may have actually better gains in density from exercise than those with normal bone density. So we need to take this into account, but that's really where things stand at this point.

Dr. Tabatabai:

Excellent. So it sounds like consistency is needed and this should be something really habitual for all patients who have bone density concerns. Dr. Sellmeye, back over to you. We spoke a little bit about vitamin D and it seems now that whenever I hear about vitamin D in the clinic, the question of vitamin K comes right behind it. So a lot of supplements now are sold in combination. So for example, a vitamin D three K two combo, et cetera. So it seems like vitamin K is really surged in popularity. Do you believe that supplemental vitamin K is needed and which type would be more beneficial and could there actually be some harm from too much vitamin K? What are your thoughts on that question?

Dr. Sellmeyer:

Nutrients other than calcium and vitamin D have very little data in terms of skeletal outcomes. And so every nutrient is important for bone health and some have a very critical role in bone health. Vitamin K is one of those osteocalcin, which is a key protein for bone formation is carboxylated in a vitamin K dependent fashion. So there's no doubt that vitamin K is super important for bones. There've been a handful of small studies, pretty limited outcomes was a meta-analysis, a couple of meta-analysis looking at putting EC limited K one, K two, MK four, and there really isn't a consistent picture on benefits of vitamin K supplements for bone health. So there've been some suggestions in some studies, but no consistent effects shown across a number of studies. Although the data are very, very limited. There's also kind of a popular theory that you have to take vitamin K and vitamin D together because that helps the vitamin D and the calcium know where to go when it goes to the bone instead going into the vasculature.

And that theory comes because one of the proteins that inhibits calcifications in the vasculature matrix flaw protein is also carboxylated in a vitamin K dependent fashion. And so I think that's where people are trying to tie this together. So if you take the vitamin K, then it inhibits the matrix RO and the calcium's going to go to the bone instead of the vasculature. But we really don't have any evidence that that is the case. And as I explained to patients, it's easy to see that we might need calcium vitamin D supplements because those are available in very few foods. It's pretty much impossible to get enough vitamin D from food and calcium is available in a very limited number of foods. So you can have pretty healthy diet and not get enough calcium and vitamin D. It's a little less clear that that's possible for other nutrients because other nutrients are more ubiquitous in our foods.

And if you're eating a reasonably healthy diet, you are probably going to be getting enough of these other nutrients In terms of downside, because it is so popular, everybody really wants to take some vitamin K. I can't really find a downside in people who do not have clotting disorders for vitamin K supplements around the RDAs. Those people are really, really wanting to take some vitamin K. I think 80 or 90 micrograms of vitamin K is probably fine. I can't find any specific harm about probably causing other than people who have clotting issues or on anticoagulants about and that sort of thing. So if pH ask, it's fine, it's probably fine to do that, but I don't have any evidence that it's benefiting you.

Dr. Tabatabai:

That's really great to know. Maybe a big waste of cash really on those pricey D three K two combinations.

Dr. Sellmeyer:

Unfortunately, I think that is the case.

Dr. Tabatabai:

Right, absolutely. Rebecca, in terms of exercises, when you're seeing a client, a patient with osteoporosis, are there ever any specific exercises you advise them to avoid? Completely.

Rebekah Rotstein:

So this comes down to the individual and fracture history, other elements of injuries, et cetera. But essentially anything that any kind of load that exceeds the strength of the bone can lead to fracture. So it's a fine balance right now where guidelines have also moved toward is away from scaring people into thinking that they can't do things and to pointing out certain movements that they might need to modify. So what are these, especially when we're talking about the spine, this includes end range spine flexion. So an example would be rounding your back completely weighted. So I think of this as loaded flexion. This is something that's really common actually in Pilates mat exercises, some yoga poses, you're lying on your back and your feet and your hips are in the air. So the entire spine has load on it in that flexed position, rapid, forceful type of movements as well.

And this is all specifically with the spine we're referring to just repeated repetitive sustained type of spine flexion. You keep doing that over and over, but specifically really when we're looking at combined movements of flexion, lateral flexion and rotation and that combination of the three is what might put too much force on an osteoporotic spine or a spine with low bone density. And especially we can't necessarily separate to say, oh, well if this person, this patient or this client has osteoporosis, it's different than if they have low bone density because of the greater number of fractures that have actually occurred in osteopenia range or low bone density. So we do just want to keep this in mind for the individual. So knowing the individual's history is important, and especially if there has been a spine fracture that makes it much more clear that you might likely avoid these types of movements because we want to make sure that we don't incur a secondary fracture.

Dr. Tabatabai:

Absolutely, safety is always first. I have unfortunately had patients who maybe work with a physical therapist, so sort of in a medical setting as they're rehabilitating for a fracture and some have actually incurred additional fractures. So I think there's education needed really across the board for physicians, for patients, for physical therapists because you really can't tell who has osteoporosis just by looking at 'em clearly. So Dr. Sellmeye back to you, just on the topic of popular supplements, magnesium comes up a lot as well. So clearly all of our patients are reading the same nutrition blogs or the same sort of health magazine, but do you feel there's any benefit to supplemental magnesium? And if so, which types might be the most helpful?

Dr. Sellmeyer:

Magnesium is also critically important for bone and about two thirds of our body's magnesium is in bone, it's on the surface of the bone and it is also involved in bone formation. So kind of similar to the vitamin K story, there is no doubt that magnesium is very important for still health and especially for bone formation. The data on magnesium are extremely limited right now. We don't really have any evidence that supplements will improve any bone outcome, but it is very, very limited data. One potential benefit to magnesium is, and something I was warn patients about in terms of a side effect is it does tend to loosen stools. So people who are having trouble with constipation from their calcium supplements, if they get a calcium magnesium combo supplement, sometimes that can actually help them tolerate it a little bit better. And if you look at population-based surveys, magnesium is one of the nutrients that we tend to be low on. So typical intakes are below the RDA on average for magnesiums, again, it's another one that if you want to supplement a bit of magnesium, I think it's fine. I don't think it's going to hurt us. I tell 'em stay RDA or less, which is around 300 milligrams per day. And if they're that much or less, I think they're probably fine and they're not hurting themselves just to be aware for any potential GI side effects.

Dr. Tabatabai:

That's really helpful to know, Rebecca. And speaking about balance, you mentioned how important that is in fracture prevention. Are there some specific exercises that patients can do to improve their balance and reduce fall risk?

Rebekah Rotstein:

Definitely. So even strength training and resistance training as I mentioned before, can have a carryover effect to balance, but you can also be just targeting your balance through the various systems or three systems of balance, visual, vestibular, somatosensory, proprioceptive. So working on any of these can be useful, but things that are really accessible would be something such as walking tandem, walking like you're walking on a tightrope, then you add in the or you mute even stimulus changes. So for instance, you turn your head, you close your eyes, bringing in things like dual tasking is really effective. That's when you're doing more than one thing simultaneously and especially when one of those is a cognitive task. So for instance, you're walking on your tight rope, you're turning your head and you're counting backwards from a hundred in increments of six. So these are ways that you can make things challenging but also really effective.

You can try standing on one leg while you're moving a limb while you're tossing a ball. It's an example of dynamic balance. We've seen that dynamic balance is more important when we're looking at fall prevention than just static balance. So while it's useful to try standing on one leg, there's a greater relationship to falls when somebody has poor dynamic balance. Other things, especially if you're thinking of strength training, things that are like lunges, those functional movements we were talking about, it's very useful and it's also very relevant. And how do you get up from the ground, right? You might lunge or you might place one foot down and then you rise from there. So that's an example of a functional exercise that can carry over into strength training, exercise that also utilizes balance. But then there's also things like dancing. So one of the other big takeaways here is when it comes to consistency, people also have to consider or we should be considering things that bring joy to people, what is enjoyable? So if you enjoy the exercise, you're probably going to be more likely to do it. And then compliance comes into play. Dance is another thing that can be very effective because it can be a social activity. It's something that people might not think of as quite exercise if maybe they're resistant to doing other forms of exercise. And as I was mentioning before, there's things like Pilates, tai chi yoga that have a really strong proprioceptive and balance component to them.

Dr. Tabatabai:

That is so helpful. Balance is really critical I think for every single patient, but especially our older population that potentially may not be able to do as much in terms of the resistance or the weightbearing, but if their balance can be improved, that's a huge step in fracture reduction. So that's very helpful. Dr. Sellmeier back over to the supplement world, which is at our patient's fingertips, especially with the wonderful internet and all of the information it provides. Strontium is coming up more and more in conversations when patients come in, they'll often bring their supplements in a little bag and show you these various concoctions that they may have purchased online or at a functional provider's office. Is there any role for strontium or for boron in the management of osteoporosis? And as far as strontium goes, is strontium citrate any safer or better than strontium ranelate?

Dr. Sellmeyer:

So strontium ranelate is the only form of strontium that has any data at all. And so it was developed as a proprietary compound and available in Europe and it has good fracture data. So both spine fractures and a lesser extent hip fractures were reduced on s strontium ate compared to placebo. After s strontium, Renate was on the market for a few years, there was a reported adverse event that there were higher rates of thrombosis on s strontium renate that was kind of added to the label in Europe. And then about 10 years ago in post marketing surveillance, it was demonstrated that there was a higher rate of nonfatal myocardial infarction on the strate compared to placebo, sorry, to patients who were taking STR had a higher rate of not myocardial infarctions than the general population. And so at that point it started undergoing more intensive review by the EMA and more and more restricted and the final ruling left it on the market but recommended it really only be used in people who had no other alternatives for bone health.

So the company that was making it in Europe stopped taking it. And my understanding is it's available in a generic form in the uk but is the only place that strontium is still available. So what's available on the internet and in health food stores is not strate, it's strontium carbonate or strontium citrate. And there are no data on those preparations whatsoever. We have no idea if they do anything for bone or if the bioavailability is the same or what an equivalent dose is. We really don't know. And the other problem with those compounds is strontium incorporates into bone, so it incorporates into the hydroxy appetite crystal and strontium has a higher molecular weight than calcium. So when bone density NNC machine does the x-ray penetration is calculating bone density, it's expecting a normal composition of hydroxyapatite. And so if there is a big fat strontium sitting there, the bone density machine interprets that as a huge number of calciums not as a single big fat strontium.

So artificially increases bone mineral density. And in the clinical trials of the strontium renate, they did bone biopsies and serum strontium levels and they tried to come up with some kind of calculation to correct the changes in bone density, which were enormous in the trial to try and get rid of how much was artifactual compared to the due to the strontium. And it's probably about 80 to 90% of the changes in bone density are artificial on strontium. And so if we have people taking amounts of strontium from other corporations, we don't know what bioavailability is, we don't know how much is in the bone going to, we could potentially see changes in bone density and interpret those clinically and they're really completely artificial. So I try to really steer people away from strontium. It's gotten easier because of the heart attacks and blood clots and all of that that led it to be restricted in Europe.

So I can tell people it messes up your bone density. There was higher rate of vascular issues and it's been withdrawn in Europe and that usually will get people off the interest in boron. There's a lot interest in boron. We know a little bit boron, there's not even an RDA for boron, so we have absolutely no idea what we should do with boron. There's a little bit of animal data. It may be involved in vitamin D metabolism or maybe important for in animal models in vitamin D deficient animals, but there is just nothing we can really say about boron.

Dr. Tabatabai:

Sounds like a data free zone for boron. So it's interesting how patients can really latch on to supplements. And it's understandable really because supplements seem safe. They seem more benign than a lot of the prescription medicines that we have. But it's always important to gently remind patients too that these supplements, so-called supplements are not FDA regulated. They're not FDA approved or monitored in any fashion. And so it always has to be safety first. And if strontium is artificially elevating bone density, that's going to leave a lot of patients sort of unprotected when it comes to fracture risk and that could really be harmful in the long run. So that's important to know. Rebecca, back over to you. Are there any common misconceptions about exercise and its role in osteoporosis management that you frequently encounter? And how do you respond to those when you hear them?

Rebekah Rotstein:

I do, and it's a really interesting time right now because we're seeing some of the misconceptions shift. So traditionally what we've seen is that those with osteoporosis can't lift more than 20 pounds. That's been a common one that if you have osteoporosis, you can't jump, you can't round your back, you can't twist it all. And as I was just pointing out, that has shifted quite a bit in terms of even recommendations, but these misconceptions still prevail and yet we're also seeing the opposite side. So it's kind of extremes. Now what I I'm starting to see a lot of is that everybody must lift heavy lift heavy weights. What does that mean? First of all, it's relative. They're really referencing the high intensity that I was talking about previously. So much of this is based on the individual as well. And I think that's one of the biggest things is that people are trying to make very blatant statements, not recognizing that osteoporosis is extremely individual.

I was diagnosed when I was 28 years old and certainly, and even if I had the exact same bone density as somebody who was several decades, my senior, there are so many other factors that are at play, I'd had no fractures, right? That's one thing to consider. But certainly also function is a huge thing. And I think when it comes to osteoporosis from the exercise standpoint, our approach as whether you're an exercise specialist or you're a physical therapist is very different from that of a physician because our primary lens that we're looking through is function. How does that person function? Because that's going to completely dictate what is the appropriate course of action for them. So it might not be appropriate for somebody who has had multiple compression fractures to be jumping, whereas somebody who even has a T-score of minus 2.5 and yet has been exercising for a while has been conditioned up to the point where to be safe for them to be doing jumping exercises, it's totally fine. So it really does depend on the individual, but I would say being cautious of any kind of extremes because that really never takes into account what is going on in an individual basis.

Dr. Tabatabai:

That's really helpful to know. And as sort of a tie in to all of his talk about exercise and muscle, Dr. Sellmeyer, talk to us about sarcopenia. So sarcopenia has also kind of come up and been more of a focal point when we're discussing aging, the elderly and osteoporosis and sarcopenia often accompanies osteoporosis. Do you recommend any specific amount or type of protein intake each day for your patients? Does animal versus plant-based protein matter?

Dr. Sellmeyer:

I could talk to you about protein for probably a full hour, and there's a lot of very, very interesting protein data. Establishing protein requirements is extremely difficult because protein requirements are established by doing nitrogen balance studies. And in order to do nitrogen balance study, you have to bring the person into neutral balance. So if you bring them into neutral balance and then you do nitrogen studies to determine their requirement, does that really reflect their endogenous state where they were pro or nitrogen losing before you brought them into balance to do the study? So establishing protein intake requirements is very, very difficult to do. So there's one RDA for everybody, and that's 0.8 grams of protein per kilogram of body weight. And that's the same if you're an 80-year-old frail person or if you're a toddler or if you're a stubo wrestler, it's exactly the same.

And I think we all recognize that is not probably appropriate. And so there are a lot of settings where people need more than that. People who are very physically active, long distance runners, older folks, there's a lot of people that we're pretty sure need more than that, but what they do need is not clear. So kind of the best assessment for older folks, they probably need somewhere maybe one gram per kilogram, maybe even up to 1.2 grams per kilogram of body weight and probably depends also on your goals. Are they losing muscle? Do they have low bone density? What their overall are they underweight what their overall nutritional status and goals are? But they probably need more than that 0.8 grams that we quote for everybody. In terms of animal and vegetable, in terms of getting enough protein and protein for pos, it probably doesn't matter.

The animal protein story really goes back kind of the acid-based balance in the diet. And so it doesn't really matter where you get your protein. I think the more important feature is making sure you're getting enough base and base is really alkaline potassium compounds in fruits and vegetables. So you get your protein wherever you want. I think the more important thing is that we are nutritionally, we are not really rich in fruits and vegetables for a variety of reasons. It is better to increase levels, but one of them is because that increases the amount of base in the diet. We have a reasonable amount of evidence that a high acid diet and net acid producing diet probably does have a detrimental effect on bones and using alkaline potassium supplements, it's one of the few nutrients. We actually have some decent bone density data showing improvements in bone density with alkaline potassium compounds.

So I think there's definitely a good bit of evidence that having an alkaline based diet is probably beneficial to bone and it'd be wonderful to be able to do a fractured trial. But those are so big and so expensive and I and others have tried to get those going and there's just not enough, nothing interested in trying to do a fractured trial with alkaline potassium compounds. But after calcium and vitamin D, the alkaline potassium compounds have the best data and they would by far be the next most likely candidate to pursue a fractured trial. So I hope that will happen at some point. But for now, I think the data are telling us that from a protein standpoint, either animal or vegetable sources is totally fine, but what's probably important is to increase the amount of base in your diet and that can be done by consuming potassium bra fruit of vegetables.

Dr. Tabatabai:

Fantastic. And now I'll throw you a bit of a loop here, and that is prunes.

Dr. Sellmeyer:

I love the prune data. The prune data are some of my favorite data. I don't know what's going on with prune, but prunes are accumulating a decent amount of data in terms of bone turnover markers and even some bone density data. So I do not know what is up with prunes, but they have some backing behind them and I can't believe any downsides. They're reaching a lot of flavonoids. They're rich potassium. So I don't know what the active compound is, but there is no problem having some prunes because they actually have a fair bit of data.

Dr. Tabatabai:

I love that. And that will also help with constipation maybe from the calcium intake. But I just want to thank both of you so very much. This has been fascinating. I'm here with Dr. Deborah Sellmeye from Stanford and Rebecca Rothstein of Buff Bones, and I think we've had just a great conversation on bone health optimization with food and fitness. So I want to thank both of you so very much for your time, and thanks for listening to this ACE podcast.

Speaker 1:

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