Podcast Episode #77: The 4 Supplements That You Should Definitely Be Taking
29 Jan 2026 · 30 min
A listener Q&A podcast (Ben Greenfield) focused on practical wellness and performance advice. Core recommendations: four baseline supplements (vitamin D, omega‑3, magnesium, greens), cautions about nightly acetaminophen/Tylenol PM and liver risk, explanation of oxalates and when to worry, caffeine timing relative to sleep (stop ~6 hours before bed), multivitamin-driven urine color (water‑soluble vitamin excretion), and running/functional training tips.
Chapters
In this podcast episode, how to decide which supplements to take. Tylenol PM for sleep, what are oxalates, coffee in the evening, multivitamins and urine color, and how to run faster.
Welcome to the BenGreenfieldFitness.com podcast. We provide you with free exercise, nutrition, weight loss, triathlon and wellness advice from the top fitness experts in the nation. So whether you're an Ironman triathlete or you're just trying to shed a few pounds, get ready for non run of the mill cutting edge content from BenGreenfieldFitness.com.
Hey podcast listeners, this is Ben Greenfield and I am back from the health summit that I spoke at down in El Dorado Hills, California. I'm in town for a week at home and then I head down to Texas to teach a eight day triathlon training camp down there. And for those of you who like to follow triathlons and triathlon training, I'll be releasing a lot of video footage of that over at the Ben Greenfield Fitness YouTube channel. For those of you just joining the podcast, these podcasts are primarily listener Q and A on human performance, fat loss, nutrition, and a host of other wellness related topics. And typically we have an expert. But for the next few weeks, just because I am doing a lot of work on a website called rockstartriathlete.com I'm actually primarily limiting this podcast to Q and A. And then we'll resume our expert interviews in just a couple of weeks. And I have some good ones lined up, including an interview with Nancy Appleton, the author of the book Suicide by Sugar, and an interview on testosterone and testosterone replacement in both males and females with Dr. Richard Cohen. Now, before we launch into this week's listener Q and A, I did want to let you know if you are a triathlete and you are listening in, then you may be interested in learning that I have come into possession of two extra triathlon training outfits. The triathlon kits, the top and the bottom, branded with BenGreenfieldFitness.com logo. So if you want to get your hands on those, I've got one medium top and medium bottom for men and one large top and large bottom for men. Just email ben greenfieldfitness.com that's the same email address that you want to use. Ben greenfieldfitness.com if you have a question for the podcast. And remember, if you want to have a call in question, and we have a couple of those today, you can call toll free to 877-209-9439 or you can Skype pacificfit.net and so let me know if you have a question or if you want to get your hands on either of those triathlon suits. Just had a couple left over after I distributed them to all my athletes. So let's go ahead and move on to this week's Listener Q and A.
Listener Q and A.
Our first question this week comes from listener Kai. Kai says here's a fundamental question regarding nutrition. How can the average person make educated decisions on what their intake should be? There's a massive amount of information out there regarding what people should or should not take in terms of supplements. But the challenge is deciphering what is valid science and what is marketing good. Recent example, I know you had a podcast on fish versus Flaxseed oil and the verdict was flaxseed. At an intuitive level, the analysis made sense to me. I opened up the recent issue of Men's Fitness and there's a small paragraph about some study that concluded flaxseed was linked to something bad. Don't have the article in front of me now. It seems very difficult at times to make intelligent decisions given the volume of conflicting information out there. Any guidance on some basic principles, rules? Kai, that's an excellent question. Question. And I do agree that it gets frustrating, it gets confusing sometimes when research study one says this and research study two says that and five years ago they said eggs were good and now they say eggs are bad and then five years from now they say eggs are good again. And I know that that's especially frustrating when you're trying to figure out how to take care of your body. Believe me, it's frustrating for nutritionists and trainers and advisors as well because we have to constantly be wary of what new studies are saying because a good nutritionist will listen when clinical studies indicate that something may or may not have the effect that we once thought it would. However, traditionally over the past several decades, there have been certain supplements that there is certain solid consensus people would benefit from utilizing. Okay, these are the rules that I follow with all the people that I work with. There's four of them that if I had my way, everyone would take. The first is something that many studies have been done on deficiency of this sores in the US and there is tons of new research every day in very large studies of over 15,000 people that people tend to be deficient in this supplement and that is vitamin D. Okay? So write that one down as one that you definitely want to take. And when you're looking at the amount of international units that you Take understand that the RDA for it is still a little bit low. I personally to tell you what I do, I take 4,000 international units of vitamin D per day. I do a sublingual spray of vitamin D under my tongue and that's my dosage on a daily basis. I live in a northern climate. Those of you in Florida and California can probably get away with a little bit less than that, but vitamin D would be one. The next one that I would highly recommend would be an omega 3 supplementation source. Lots of Japanese studies and also several US studies have shown omega 3s to be highly important in reducing chronic inflammation in a host of diseases linked to chronic inflammation. Omega 3 fatty acids, like you mentioned, you can get them in flaxseed oil, you can get them in fish oil. Okay, regardless of the little things that creep up here and there. Like I think that recent article in Men's Health you were talking about was finding that flaxseed oil had lower components of something called lignans. And it is true that some forms of flaxseed oil, especially those that don't tend to put the lignans back into the flax seed after it's extracted, can be lower in lignans and so they don't have as great of an anti cancer effect compared to fish oil. Regardless, take an Omega 3. You know, it's up to you whether you do the flaxseed oil or the fish oil. You're getting benefit out of either. But take an Omega 3. So we got that. We have vitamin D. The next one that I would highly recommend everyone starts supplement with is magnesium. Again, something that lots of people and especially athletes tend to be highly deficient in. I could talk for hours and hours about this. Dr. Carolyn Dean, whose guest post I recently put@BenGreenfieldFitness.com has written an excellent and comprehensive book on the topic. One of the best books that I read in 2009, it's digestible by the general population and it's called the Magnesium Miracle. I recommend that you pick up that book and read it. There are many studies that show that the RDA for magnesium is probably too low and people need to be getting more of that as well. Again, what do I personally do? I do a topical magnesium. I generally go about 15 to 20 sprays per day and it gives me about 400 milligrams or so of magnesium. How you take it is up to you, but that in addition to vitamin D and an omega 3 fatty acid would be something I'd recommend Then the last one, not a lot of studies on it, but anecdotally with myself and everyone that I've worked with who has started into some form of a greens supplement has benefited highly. Greens supplement means that it's got a blend of different high fiber foods, things like spirulina, algae. Lots of times there are mushroom extracts, there are digestive enzymes, there are probiotics. These are getting very popular because people are realizing that a lot of times they're not getting what they need out of fruits, out of vegetables and out of their day to day nutrition. And greens multivitamin, although there's not a ton of solid studies behind them, I have found in every person across the board that I recommended a greens supplement to, they immediately begin to feel a difference. And the most stark difference that they see is the drop in the frequency of colds and and immune system problems that they have. Okay, so those four, if you're going to choose anything, those four and then everything else, you know, we could talk for hours. But those four I would definitely add into your program. So those would be the basic, basic principles I would go by. And then just keep your ear to the ground on the research because it changes all the time and typically the newer research is better just as better and better scientific methods come to light. So listen to the research, just don't get too confused by it. So the next question is from listener Brian who says, do you have any thoughts on the use of Tylenol pm? Even with heavy training and being tired, I still have sleep issues of falling asleep or being such a light sleeper, I awaken throughout the night to overcome such. I've been using the Tylenol PM but I don't like and wondering about using it often. Well, the idea behind Tylenol PM is that it is acetaminophen and acetaminophen is something that you can find in higher dosages and things like non steroidal anti inflammatory drugs like ibuprofen and Aleve. But the idea behind it is that it's an anti inflammatory problem. Of course with it that most of us are familiar with is that there can be some pretty serious liver problems, gastrointestinal side effects from frequent or heavy use of acetaminophen. So I would be careful. Tylenol PM is gonna have a little bit lower acetaminophen levels than some of these non steroidal anti inflammatory drugs. But you are going to want to be aware that there can be a problem with liver and kidney toxicity and that can be Amplified if you're exercising in hot weather when you have acetaminophen in your system. That's why I recommend that anybody that's going to go out and do, you know, an ironman in hot weather or a marathon or something like that not have ibuprofen in their body when they do so. So you could take supplements in conjunction with acetaminophen to help balance out some of the damage that can be done. Milk thistle extract and Jerusalem artichoke extract would be two natural compounds that are generally accepted as something that can protect or cleanse the liver and in natural medicine are used for degenerative liver diseases, taking in antioxidants, specifically things like selenium, vitamin E, vitamin C. There's another really powerful one called alpha lipoic acid. All those would also help you fight off some of the things that acetaminophenia could be doing to your body. Ultimately, when you're putting something like that into your system on a nightly basis, it is going to potentially cause some issues. I would play it on the safe side and try to go with a more natural sleep aid. I personally, when I have trouble sleeping, I use about 6 milligrams of melatonin. Younger individuals can get away with about 3 milligrams. I know some older individuals that take 10 to 12. The older you are, typically the less melatonin your body is going to make. I also occasionally take something called Somnidrin gh, made by a company called Millennium Sports. They make a bunch of different supplements that I primarily use for sports performance. But they do have this sleep aid that I find works pretty well. You just don't want to use it all the time because you would grow tolerant to it. So that's the deal with the acetaminophen and the Tylenol pm. Just be careful. And the next question comes from listener Jason. We're getting lots of nutrition questions today. Jason says, what are oxalates? And should I be concerned eating too many of them? If I especially enjoy eating foods such as sweet potatoes and spinach. I've read about certain foods containing enzyme inhibitors, and I'm wondering if this is the same as oxalates, and if so, should I possibly be avoiding those as well? Well, the idea behind oxalate, Jason, is that it's just basically a simple molecule that can link up with something like calcium in your body and, and it could crystallize. And so a high, high level of oxalate intake could technically cause something like kidney stones and it could technically interfere with some of the absorption in your gut. And some of those high oxalate foods would include some of those that you mentioned, like the spinach, the sweet potatoes, rhubarb is in there, beets, some nuts, chocolate has a lot of oxalates. Tea, green tea, black tea, you name it, has a lot of oxalates. Coffee does cola, wheat bran. So there's a lot of foods that tend to be high in these oxalates that if you had issues with kidney stones or something like that, you may want to consider limiting. However, I am not of the opinion that people need to be too concerned about oxalates, especially if they're well hydrated, if their minerals are balanced, you know, supplementing with something like magnesium that I talked about earlier. Unless you have a medical condition that is basically aggravated by a high oxalate intake, I wouldn't worry about the oxalates too much. I think that that's a little bit blown out of proportion for somebody to try and be on a low oxalate diet just so they can be healthier, because a lot of the things that contain oxalates also contain specifically pretty consistently high, high amount of antioxidants. And so it's, it's something that you're, you're going to be missing out on if you completely cut out your oxalate intake. The question about the. How did you put this? Enzyme inhibitors? I've never come across any research that shows oxalates to be enzyme inhibitors. I think what you're probably thinking of is the phytic acids that people talk about with soy and how that can interfere with the activity of enzymes in the gut. Not a lot of research out there on that. There's a little bit of anecdotal research. I personally just try to limit my soy intake. I'll do tofu maybe a couple times a week. I don't drink a lot of soy milk. Soy bigger concern is for females who take in a lot of soy as far as the estrogen levels are concerned. But I wouldn't worry about a healthy diet that has a little bit of soy here and there, some sweet potatoes, some spinach. Once you start to get too nitpicky, it just starts to get a little bit silly. So that's the deal with oxalates. Jason and good question. Listener Tracy asks finally a training question. I'm interested in finding the best resources on functional training and wondered if you could tell me what you recommend. I live in Canada, but where I've just begun to teach cage fitness classes and I'M a certified personal trainer who does in home training with clients who have little or no equipment. I bring along bands and some light weights, but I'm limited in the amount of weight I can bring to my clients. I am new to personal training but I have been doing MMA for a few years and I have found that body weight and functional training are the best for overall fitness and I'd like to have an arsenal of functional training exercises that range from beginner to expert to use with my clients. First of all, Tracy, I'm big into functional training and I have a huge free exercise photo and video database that I use with the clients that I work with over at Now. I'll put a link to this in the show notes pacificfit.net go over there, scroll through there. Lots of free exercise photos and videos of some of the functional routines that I rely on. The other thing I would recommend to you is I wrote my entire book shape 21 to be done with body weight and occasionally a set of dumbbells. The other thing that I really recommend you add to your arsenal is the gym stick and you can find that@bengreenfieldfitness.com gymstick and I'm saying all this realizing I'm starting to sound like a commercial now, but I'm so into functional training that I do have quite a few products that I'm affiliated with that our functional training type of product. So check out pacificfit.net check out my book Shape 21 and then also get your hands on a gym stick. It really is great for some of those functional training routines that incorporate minimal equipment. Listener Pete asks you talk about green tea or coffee in the morning before going for the morning movement session and was wondering about any similar protocol before bed. I've been making sure I eat at least two hours before sleeping though I am curious to know if there is any benefit adverse effect from drinking coffee or green tea within that two hour period before sleep or should I just stick with water? Obviously some people have trouble sleeping as a result of the caffeine, though I never really have this problem when you refer to the morning movement Pete, for people listening in, I'm talking about the idea that caffeine can accelerate the fat burning effect and if you take that prior to a morning fat burning session on an empty stomach, it can accelerate the rate of weight loss. Now as far as using caffeine the rest of the day, as many of us know overuse of caffeine you can get fatigue and depression, irritability, jumpiness Most importantly, though, it can actually constrict the blood vessels in the brain. The reason it does that is because caffeine is an antagonist or it reduces something called adenosine. And adenosine is a component that binds to the part of your brain that prepares your nerves for sleep. And so when you block those adenosine receptors, you actually inhibit your ability to fall asleep. Well, you also inhibit your ability to achieve a state of deep sleep. So even if you can fall asleep, it's likely that you're not going to have as high quality of sleep. So although you could get a little bit of fat burning assistance from caffeine, and there's a bunch of other studies on caffeine showing that it can reduce the risk of Parkinson's disease, reduce the risk of colon liver cancer, skin cancer, liver psoriasis, gallstones. There's a bunch of research out there that's favorable towards caffeine. I would use it in moderation and I would definitely. If you value deep sleep and all the recovery and health benefits that deep sleep can give you, avoid taking caffeine prior to bed. You've got a half life of caffeine of about three hours, and so it is going to be in your system for six hours. I generally will quit any caffeine intake after about 5pm, especially from a cup of coffee, which tends to be the highest source of caffeine. Unless I plan on staying up very, very late, I don't use it. So. Great question. And then we have a question from listener Jason who says, I've been listening to your podcast for a few months now and I just had a question for you. I've recently started taking a multivitamin. I've noticed the color of my urine is much more yellow than it was previously. I typically drink a lot of water during the day and always have clear to lightly colored urine. So I don't think that dehydration is responsible for this change. I'm guessing this color difference is due to excess vitamin which is not absorbed by the body being excreted in the urine. My question is, is this safe? By ingesting more of certain vitamins and minerals that my body is using, am I making my kidneys work overtime to get rid of the excess? The point of taking the multivitamin is to benefit my health. I want to make sure I'm not unknowingly damaging it. Also, if you think it is okay to continue to use. Are you familiar with this product and do you think it is a good choice for a Multivitamin. Many thanks for your help and I love listening to your show. And when he asked about the product, he had actually brought up one in his email called the Rainbow Light Complete Nutritional System. You know, I checked out the nutrition label on that and it's actually, you know, it's one of those multivitamin that includes a lot of those green supplement components that I talked about like broccoli powder and vegetable juice extract. And anytime your multivitamin has some of that stuff in it, it is going to give you a little bit of extra bang for your buck. But as far as the dark urine color goes, yeah, typically that is excess water soluble vitamins that your body is excreting. It's not in any research studies shown to be damaging to your kidneys. To get, you know, some extra, in this case, typically it's going to be vitamin C or vitamin B. I would of course make sure that you are hydrated and that you're drinking a lot of water. But I wouldn't worry too much about your kidneys and that excess water soluble vitamin. The kidneys are pretty amazing little machines and I would be a lot more concerned about the effect of, you know, toxins and preservatives and artificial compounds and alcohol and their effect on other organs in your body more than I would worry about excess vitamins, especially water soluble vitamins causing damage to your kidneys. Now anytime I answer questions like this, you guys got to remember, I'm not a physician and I'm not a registered dietitian. My role is not to control disease through the use of nutrition. I'm just giving you little bit of advice and my opinion on the question that you're asking. So listener Lisa says I'm new to your podcasts, which I think are awesome and new to triathlon. Thank you, Lisa. I did a few sprint distance races last year and my goal is an Olympic distance race this year. Here's my question. My swim and bike times are competitive with my age group. I'm 43, but my runtime is slow. It's killing my overall time. How can I improve my speed? First of all, I'm going to start with the painfully obvious. I've never seen you before, Lisa, but this is the number one thing that I find people new to triathlon have an issue with when it comes to running faster, and that is weight. You would be floored at the difference between running at whatever weight you're at now and running at 10 pounds lighter. You know, I personally, I've run at 210 pounds, and I've run at 175 pounds, and I can tell you, you feel light as a feather, and you just bound when you're light. So get your nutrition dialed in, make sure you have a good, healthy body fat percentage and watch your weight. I would strengthen your hips as well, specifically the gluteus medius muscles. Those are the ones that work when you extend your hips out to the side. Make sure those are strong, as those are going to really support your leg and single leg stance. And when I do run, gait analysis on people in my biomechanics laboratory, I find that especially in females, that tends to be a weak muscle. It collapses. You can see the core collapse. The foot spends a long time in contact with the ground, and the running time decreases. The running time technically increases, you get slower. A couple other things would be, at the same time as you're strengthening your hips, work on your core musculature. That should go without saying. And then I would also, if you do have a healthy weight and you're not excessively heavy, look at incorporating plyometrics into your program, which are jumping and explosive and power type of movements, because those will also improve your ground reaction time and decrease the amount of time that you spend in contact with the ground. Okay, so explosiveness, hip strengthening, weight loss, core strengthening, all those can help. And then making sure that you're not running at a single speed, which is something that a lot of athletes do. They go out and they just run at one single speed all the time, 75% kind of uncomfortable, kind of breathing hard, not too bad. If you replace that with slow, fast intervals, you will get faster, much faster. And then the last thing that I'm now utilizing in my run training because I want to get faster, is visualization techniques where I actually close my eyes every day and I tell myself that I'm a runner, that I'm a fast runner. I picture myself bounding and leaping and running at the speed that I want to run. And I'm basically trying to reprogram my brain to accept the fact that I can be a faster runner. And that's actually working out quite well. The amount of confidence that you have when you're running definitely increases when you do that. Next, we have a call in comment from Jeff.
Hey, Ben, this is Jeff from Tampa. More of a comment than a question, but curious if you could make available perhaps a marathon Dominator package. For those of us that are marathoners and not triathletes, we'd love to have also some of your other kind of tips and extras that come along with the Triathlon Dominator package as well. So please consider and thanks for your comments and thanks for Great show man. Take care.
Bye.
Hi Jeff, that is a great suggestion and the triathlon dominator@triathlondominator.com for those of you listening in who don't know what that is, just go to the website. It is designed for triathletes, not marathoners, as you probably know, Jeff. But this brings me to a very important thing and that is the fact that whenever I sit down to write a book, to create a program to record a CD or a video, it's almost 100% based off of what someone has written to me or multiple people have written to me and requested. And what I do is I will put that request off to the side and put it into a folder and eventually I get to a lot of the requests. You guys wonder how I think about how do I write Shape 21, the book about how to eat without consuming foods that you might be allergic to? Or why did I write 100 ways to boost your metabolism? Or why did I do any of this stuff? I don't lay awake at night and get these ideas. People write in to me and ask stuff or call in like Jeff did. So if you have stuff that you would like me to do, definitely call in like Jeff did. And as a result of Jeff's call in, I probably will do something for runners. I can't promise that super soon, Jeff, but it's a great suggestion. Along the same lines, I have another call in from somebody who also is using the Triathlon Dominator.
Hey Ben, this is Eric Peterson calling again from Coeur d'. Alene. Seems like I'm calling you almost on a weekly basis now with more Dominator successes. I ran the scheduled 13.1 or half marathon run today at race pace and improved my personal record, my PR by over eight minutes on that run and I followed exactly the instructions running at upper aerobic pace and then for the first half and lactate threshold with the second half and finished it without feeling really all that fatigued. So obviously the plan is continuing to work its magic and want to say thank you for a great training program and wishing you all the best. Take care. Thank you.
Well, thank you Eric and I'm glad I could help. So remember, if you have a question or comment, email ben greenfieldfitness.com call 8772099439 or Skype Pacific Fit Remember that after the next couple weeks of listener Q and A. I'm going to be returning to my interviews with health experts on this show. If you didn't read it yet, definitely go check out the latest post@BenGreenfieldFitness.com which was Carolyn Dean's top 12 predictions in wellness for 2010. Some controversial stuff, but also some interesting ideas and some interesting comments on there. And I'll be releasing the last part of that post later on this week. So until next time, this is Ben Greenfield. Have a healthy week.
Sat.
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