The Science of Supplements: What Works, What's Hype, and What Could Actually Harm You | Dr. Mahtab Jafari

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28:30So my first recommendation is diet, because if we have a good diet, and if our nutrition is balanced, the chances of needing supplements is very, very low. So really, the first place to start is to have a very honest evaluation of our nutritional intake to see how our diet is. But sometimes, even with good nutrition, you may need supplementation, and that's when you go to take a dietary supplement. But these conversations should happen with your healthcare providers. So my recommendation to people is that when you go for the annual checkup, when you go to see your physician, take your supplements with you.

29:16For instance, if I am checking your nutritional status and I see that you are high in vitamin B12, I need to know what supplements you are taking and at what doses. That is a recommendation that I always have, is to take your supplements to your doctor's appointments to make sure that you have a conversation with them. And then if you are deficient in something, first place to start is diet. Okay, this is very helpful. Thank you for bearing with me on the digression into testing. Let's go back to marching through the list of various types of supplements to get your take on them. We talked about B, vitamin B, specifically B12, which as I mentioned is something that I take.

30:01Something else that I take that I think is very common, although I'm now questioning whether I need it, is vitamin D. Many years ago, my doctor pointed out that my vitamin D levels were, in his words, in the toilet. So I just started taking a little vitamin D every day. I've also, though, started to get a little bit more disciplined about getting outside. So perhaps I don't need vitamin D and I don't even sure if the supplementation would help in the first place. So I said a lot there. What's your take on D? Vitamin D is an interesting vitamin and a very interesting and sometimes controversial topic.

30:37Based on reports, 40 % of adult Americans are vitamin D deficient. So maybe when you were deficient, you were in that group. So now the question is, how do we define deficiency? And if you go and use PubMed or Google vitamin D deficiency, it looks like almost every health association has their own definition of deficiency. The number that I use is 20. So anything less than 20 is considered deficient and it really requires supplementation. But then the question is where you are and at what stage of your life you are at, what age you have, and what are some other medical conditions that you have.

31:25So if you have somebody who has osteoporosis and you've had spontaneous bone fractures, the chances are that that you probably need to pay attention to your bone health. And you may need more vitamin D because we just don't get out as much as we should. You know, we are not exposed to sun. The use of sunscreens and everything else really reduces organic production of vitamin D that we can have naturally. So that's when supplementation is important. And how to supplement really depends on your blood level. If you are less than 20, you may have to start with 2 ,000 units a day. If you are in the, let's say, 40 to 60, you may not need supplement, but you still have to check your vitamin D levels to make sure that they don't fall short.

32:18But the recommendation is 1 ,000 units a day if you are not getting enough sun exposure. So I don't know if I answered your question. Well, I think it comes back to test your levels, talk to your doctor, and if it's indicated, take it. Absolutely, yes. And we'll probably end up repeating that as I march through this list a lot, but people need to hear it. But let me just ask a few more questions on vitamins. Vitamin C. Many people, including my wife who's a doctor, will recommend taking some vitamin C if you are starting to feel a little sick or you're worried that you've been exposed, what say you?

32:59Vitamin C is a very interesting vitamin because we have been studying vitamin C, believe it or not, for almost 80 years. And we have different types of studies, some suggesting that vitamin C is not going to do anything to your cold virus, decreasing the duration or the symptoms. And some studies suggest that it does. If you look at these studies collectively, I like to say that when you feel like you're about to get sick, taking vitamin C, not at very high doses, because I've seen people taking three or four grams, which I do not recommend, but taking maybe 500 to 1000 milligram of vitamin C is going to probably be helpful to decrease the duration of your cold maybe by 1.5 days.

33:50that that's what the summary of these studies are, but it is really not going to help much. And we have wonderful sources of vitamin C in our diet, you know, oranges, strawberries actually have more vitamin C than oranges and kiwis. If you feel like you're getting cold, and sometimes, I mean, I don't want to be disrespectful to people who believe in vitamin C, but sometimes the placebo effect also works. So if you take vitamin C at lower levels, 500 to 1 ,000 milligram a day, it wouldn't help. But daily intake of vitamin C is not really recommended. They have done studies in travelers who have taken vitamin C, compared them to travelers who didn't take vitamin C to say which ones get more sick, and there was no statistically significant differences.

34:39I don't know if they still sell this, but I remember in the airports, they would sell something called Airborne, which was, I think, a multivitamin. And you drop it in your drink and it dissolves and it tastes good. I used to take it, but it sounds like it may not be that useful. If you have a good diet, if you have a balanced, good diet, the chances of being helpful is not that high. But Airborne is still being sold. I don't know the ranking, but it's pretty high on the list of most popular and sold dietary supplements, especially during the flu season and cold season in winter. And airborne is not just vitamin C.

35:17It also has some other vitamins. It has zinc and a few other. So I think what you're saying is it probably won't help as a preventative measure, but what if you're starting to feel the first tingles and aches of a cold? Will zinc and vitamin C and maybe echinacea, will any of that help? You mentioned C might help a little bit, but what about those other supplements? There have also been studies published on these other supplements, and in my mind, the jury is still out. And there is a very minor, I would say, minor significance and minor trend towards these supplements helping to reduce the symptoms and maybe to reduce the viral load.

36:02But as I said, there are no good randomized clinical trials looking at them. And of course, the issue of clinical studies on dietary supplements is something that we can probably you spend a few hours on. Okay, one last vitamin question. I think a lot of people just reflexively and habitually take a multivitamin. I suspect your answer is just going to be run the test, talk to your doctor, but I just want to check if there's anything more to say. Multivitamins, as you mentioned, commonly used. I think last time I checked the statistics, almost 30 % of U.S. adults take a dietary supplement, and I think the number is probably higher than that.

36:45So with multivitamins, again, I want to go back to the basics. The first question is, do I need them? If I have a very good diet, the chances of needing it is pretty much zero because the amount of various vitamins that we get in a multivitamins are pretty low. So let's say you are D deficient, 40 units or 50 units of, or even 100 units of vitamin D in a multivitamin is really not going to be helpful. You have to supplement. So the amount of these vitamins in a multivitamin is important. But going back to studies, study after study shows that multivitamins are not going to improve our health. Two recent studies actually show that taking multivitamins increases mortality.

37:34So patients who have been taking these supplements, they had a higher risk for mortality. But I want to step back because this can become like a headline news that, oh, taking multivitamins is going to increase your mortality. But if you look at the populations who were enrolled in these studies, you have to ask yourself some very basic questions. So maybe people who are taking multivitamins are sicker in general. Their baseline health is not optimized. And this is why they are taking vitamins. And this is a problem that we have with most dietary supplement studies is the study design and looking at the characteristics of the populations that they recruited and were included in these studies.

38:18For most dietary supplement studies, for instance, we don't have baseline vitamin levels. This has been a big critique of vitamin D studies, especially the ones that fail because the supporters of vitamin D supplementations would say that, wait a minute, you didn't check vitamin D levels and you put these people on 400 or 1 ,000 units of vitamin D and you didn't see any efficacy, let's say, in bone fracture, cardiovascular health, immune health. So you can't really make those conclusions. And this is really an ongoing debate when it comes to studies on dietary supplements. But going back to your multivitamin question, if you don't have a sound nutrition, if your diet is not good, you may consider taking a multivitamin.

39:09But then you need to have a conversation with your physician because you have to look at that multivitamins and see how much of each vitamin you have in that supplement. And if you need more. This is just fascinating and sobering. All right, so we talked about vitamins. What are minerals? I honestly don't know. What is the difference between a vitamin and a mineral? So I give you some examples to just make it easier. So for instance, calcium is a mineral, magnesium is a mineral, and zinc is a mineral, copper is a mineral. So when you test, when you do a blood test, you can also check the levels of minerals.

39:53in your blood. A very controversial topic when it comes to mineral is the use of calcium, for instance. So we all need calcium in our diet. And I know there are ranges based on the fact if you're a woman or if you're a female or a male, I usually recommend to people try to have at least 1500 milligrams of calcium intake every day. So a lot of people reach for the supplements. A lot of people take calcium supplements because they think that the more is better when it comes to calcium. And that is absolutely not true. Going back to the baseline test that we talked about, for instance, somebody who has kidney problems, taking more calcium is really not going to be helpful.

40:38It's actually going to harm them. It's going to cause more kidney problems, and it is also going to deposit more calcium in our blood vessels. And that is going to be a separate issue because we are going to increase the risk of developing coronary artery disease. So calcium is great. My recommendation is try to get as much calcium as we can from our diet, but if we still need to supplement, we have to be very careful. Let me ask about another mineral. You mentioned it, magnesium. It's often recommended as a way to help us sleep. What's the truth about magnesium? Does it actually help us sleep?

41:17Magnesium is another interesting mineral. Data suggests that 50 % of adult Americans are magnesium deficient. You may think that we came up with that statistics because we measured blood magnesium levels, just like I mentioned vitamin D levels. We measured magnesium levels in our blood and we were deficient. And that's really not the case. The magnesium that we get in our blood tests only represents 1 % of the total magnesium in our bodies. 60 % of the magnesium in our bodies are in our bones. We are not going to get the amount that we have in our bones in a blood test. So that 50 % is based on intake because we have done epidemiological studies and we have observed that most of us do not have enough magnesium intake.

42:07And based on that, the intake inadequacy, we decided that, okay, we are magnesium deficient. So now going back to the uses of magnesium, there are some studies, for instance, suggesting in certain types of migraine, people who have migraine headaches, taking magnesium helped them. When it comes to sleep, studies have not been conclusive. Some studies suggest that it may help, and some studies suggest that it may not help. I would say that this recent study that was published actually in 2025, look at, is probably the best magnesium study, and I tell you why. Although the sample size was quite small, I think they only look at 60 adults.

42:52The good thing about this study was that the supplement that they used was standardized. It was a form of magnesium formulation, magnesium tyronate, which crosses the blood brain barrier, and then it can end up in our brain. And in that study, they showed that magnesium actually improved sleep quality. And the reason that I like this study is that it wasn't just based on a questionnaire, because I can be very subjective and ask you, Dan, how did you sleep last night? And you said, oh, it was pretty good. So that's very subjective. But in this study, they also evaluated the sleep quality with an oral rate.

43:31So what they did was that these people, they were collecting data on the subjects in this study in a subjective and objective manner. And they showed that magnesium supplementation helped them improve the quality of their sleep. But this is a small study, very small duration. I believe the study was done over 21 days. What does that mean long-term? We don't know. What I recommend to people when they complain about insomnia and sleep disorders is they again go back to their physicians and have very open and honest conversations with them. Because often, insomnia and sleep disorders could be because of some other illnesses and some other issues.

44:18So just reaching out for a supplement or even a medication to take care of our sleep is probably not recommended. And then it comes to insomnia, of course, you're talking about dietary supplements, but the science shows that cognitive behavioral therapy is probably the most robust intervention to improve our sleep. And meditation. And meditation. And meditation. Yes. We've had sleep experts on the show before, and it's been asserted quite powerfully and repeatedly that CBTI, cognitive behavioral therapy for insomnia, is the biggest winner in this category. I will say, and some of my listeners know this, I'm happy to say I had insomnia for a decade, and it turned out I had something called restless leg syndrome that actually has been effectively treated with a combination of iron supplementation and a few medications.

45:13Yes. I'm so glad you shared that example because if you probably saw a physician to get the diagnosis of restless leg syndrome, if you had not done that, you would be over-medicating and over-supplementing for your insomnia and it was not good. It was actually harmful. So now you have a diagnosis and you are tweeting the issue. When it comes to sleep, melatonin, is there evidence that it can help? Yes. Melatonin is a hormone that we all produce naturally. We all produce melatonin. Some of us secrete less melatonin, so we may need to supplement even just to improve our circadian written on a day-to-day basis.

46:02But for the most part, we have a good production. Most people have a good amount of melatonin. So melatonin could be useful for occasional insomnia. For instance, your jet lag or you're traveling, one to three milligrams of melatonin is not going to be dangerous. A recent study really raised the alarm on the use of melatonin. It was actually published four or five months ago, and they look at 130 ,000 people who were taking melatonin at least for one year, and they reported that melatonin increased the risk for heart failure in those people. And I don't want to go through the details unless you want me to, but really the premise was that it was changing their blood pressure and heart rate, and this is how these people ended up having higher risk of heart failure.

46:55This study was not published. It was an abstract that was presented at the American Heart Association Conference in November of 2025, and it hasn't been peer-reviewed. So when people ask me questions about this study, I say that the study was presented at a conference, at a scientific conference. But to my knowledge, because I checked this last week, it hasn't been published yet. And when it's published, I'm sure that in the discussion or the critique section, we are going to find out what are some of the controversial issues that we have to consider about this study. Having said that, my general recommendation is not to take melatonin on a daily basis.

47:39If you feel like you have to take it to fall asleep, then on a daily basis, then again, you need to have a conversation with your physician. One problem with melatonin is also the quality of the supplements. Melatonin can be sedative. Dr. Cohen at Harvard published this study looking at melatonin gummies, and he reported that some of these gummies had 300 % more melatonin than what they reported. That means that you can be really sedated in the morning, meaning that you shouldn't be driving and you should really worry. So melatonin can help people to fall asleep, but it's really not a sleep medication.

48:19It doesn't help you to stay asleep.

48:26Much more with Dr. Jafari right after this.

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50:58What category do omega-3 fatty acids fall into? Omega-3 fatty acids are a form of dietary supplements. So they are not vitamins. They are not minerals. As you said, they are fatty acids. And we have to get them from our diet. Omega-3s and omega-6s is not something that we can just walk around and produce. So we need to get them from our diet. And the good news is that there are different sources of omega-3s in our diet. This is another dietary supplement that there is an objective test to evaluate whether we are deficient or we have sufficient amount in our bodies. And that is the omega index.

51:42That's again another, actually you don't even need a blood test. It is a finger stick test that you can measure your omega-3 levels and the ratio of omega-3 to omega-6 in your blood. And if your omega-3 index is less than 8%, most likely you need to supplement. Dr. Justin Marchegiani My psychiatrist recommended a large dose of omega-3s as a way to elevate my mood because I've been dealing with a bit of a recurrence of depression over the last couple of months. Any evidence for that recommendation? So when we look at all the scientific studies that have been published on omega-3s, and this is another, I want to go back to the quality of clinical studies, because once again, we sometimes don't know what the baseline of the participants are.

52:38They could be deficient in omega-3s or replete, and we wouldn't know because we never check for that index. But if you look at the scientific studies on omega-3s collectively, there are some small studies that suggest that omega-3s are useful for brain health, especially if you don't have enough in your diet. But the studies are not conclusive. What we know about omega-3s for sure is that if you have high levels of triglycerides and you take omega-3s and sometimes the prescription form, not even the dietary supplements, unless again, you look for a high quality supplement, it can decrease triglycerides.

53:21So that's why omega-3s are very helpful for heart disease. Omega-3s also have anti-inflammatory properties. Some data suggests that maybe this is why they are also useful for our brain health and cardiovascular function because they decrease inflammation. I think we're now back at our theme. Some arguments for omega-3, but get tested, see what your levels are, talk to your doctor. Yes. I'm not sure we fully closed the loop on whether they can help with depression. Did you answer that part? What I shared was that there are studies, there are small studies suggesting that omega-3s can help with depression and they can help with brain health in general.

54:08Some studies even suggest that they can delay dementia. but my conclusion was that these studies were not done long-term because, for instance, with dementia, you can test omega-3s in four to six weeks or even three months and say that, they had an impact on the symptoms of dementia. The study has to be long-term. It has to go over years and maybe sometimes a decade. But what I was saying is that the data and the results are not conclusive when it comes to the impact of omega-3s on depression, for instance. But again, my own little editorial point here is that if you did take the omega-3s and you feel improvement, then that means that it is working for you.

54:56So I am not going to say, Dan, stop taking it because it doesn't work. And sometimes when I share this answer with the patients that I see or my friends, they say, wait a minute, this is a very wishy-washy answer. You were telling me to take it, but then the data doesn't show that. I said, this is when the personalization come into effect. Because if a study shows that, for instance, vitamin D is not going to help with your fractures or decrease the risk of having fractures, and I didn't check the baseline level, but it's working for you, then it's working for you. I don't find that wishy-washy.

55:36I find that elasticity to be just wise. And you know, then something else that I like to add is that science is constantly evolving. So we may have had studies that were published 10, 20 years ago, and the conclusion of those studies are not really consistent with what we are studying now. So we have to remember that when we talk about scientific evidence, scientific evidence evolves, and you're doing a better job with the quality of the studies on dietary supplements. So hopefully we will reach a point that I will have this interview, this dialogue with you and say, the studies are great. The quality of the studies are great, but we are not there yet.

56:21On the subject of depression, another supplement that was actually recommended to me by the same psychiatrist, I have not taken this, is St. John's wort. What's your take on St. John's wort? It comes from a plant, so it's a botanical extract. One of the ingredients that this botanical has, one of the hundreds of molecules that this botanical has, is very similar. The chemical structure of that molecule is very similar to SSRIs, selective serotonin reuptake inhibitors. So St. John's Warts does have antidepressant properties, but again, it has to be used under the supervision of a physician because St.

57:05John's Warts uses the same liver metabolic pathways that some other drugs use, and it may interact with them. So you really need to be under the supervision of a physician. I do not recommend people just going to a store and buying St. John's wort to improve their mood and improve their depression because with the understanding that, oh, this is just safe. This is a dietary supplement. This is a natural product and it's safe. There is nothing safe there because it can interact with your other drugs and supplements. So you mentioned that St. John's wort is a botanical, and that actually is one of the categories I wanted to ask you about, herbs and botanicals.

57:49And you mentioned early on in this conversation that your grandmother used to give you herbs and botanical remedies for various ailments when you were growing up. What is your current view on the efficacy of herbs and botanicals now. Humans have used herbal remedies and botanicals for thousands of years. In the context of traditional medical practices, when they use correctly and appropriately, we know that they work. Going back to my grandmother, for instance, if we had stomach pain, she would give us mint. She would grind up some mint, put them in hot water and give us like a mint tea. Of course, she didn't know that by putting the mint in hot water, she's extracting it because you're extracting chemicals out of the mint plant when you do that.

58:42And it helped us. Another example that I used from my grandmother is in harsh, cold winters of Tehran, she used to give us like one teaspoon of cinnamon to keep us warm. And I really hated that because it was very bitter. Years later, it was about 10 years ago that we did a study in my lab with cinnamon and we found out that cinnamon actually activates heat shock proteins. So what I thought it was voodoo by my grandmother is actually, I was able to prove it in my lab, which was very interesting. So going back to herbs, they can be effective if they are used in the right context. Again, I want to go back to the quality of the dietary supplements, especially herbal products, because unless we know the source, we know the farm that they come from, we know the quality of the product, it is really hard to make any assessment about their safety.

59:41And one thing that I always talk about is staying away from these blends, proprietary blends, because you may buy an herbal remedy and they list, I don't know, sometimes 10 or 20 different herbs. And there is no information on the dose. There is no information on where these herbs come from, where they cultivated from an organic farm, responsible agriculture practices. We don't know. I really want people to think twice when they take an herbal remedy that has many different ingredients. Okay. Well, that brings to mind AG1, which is an incredibly popular supplement. It's advertised all over social media.

1:00:24They've talked to me and my team about advertising on this show. We had a bunch of requests that I don't think went down well with them. And so they're not currently advertisers here. But so what's your take on AG1? My take on AG1 is pretty much what I just shared with you about other dietary supplements. I have not had a deep dive into this particular supplement, so I can't really share any scientific data. I don't know if they are out there, but my take is going back to the quality and making sure that the quality of the product is verified and it is trustworthy. And if you tell me some of the indications that people are recommending AG1, I can make comments on those two.

1:01:14But I think the basic pitch is that it's just a ton of, it's like having a huge salad. And I don't know if that's a reasonable claim to make, but I think that's the pitch. This is a very interesting pitch that many companies where they sell these green powders, I think the big umbrella for these kinds of supplements is that, oh, use these green powders because we have poor diets, we don't have enough fruits and vegetables, and the green powder or AG1 can replace that. If you're not eating a salad, at least do that. My take on that is the same take that I have with everything else. Number one, these are highly processed.

1:01:54In order to get to the product, you have to go through some chemical processing. Even if you're freeze-drying the herbs or the greens, that is considered processing. So they're highly processed. And then the other question is the other ingredients in these green powders because they don't taste good. So unless you add sugar and other additives, it's not really pleasant to eat them. So I want to go back to the question of quality. And finally, do you think that we are going to get the benefits of the polyphenols that we get from, let's say, a salad compared to AG1, there's really no comparison.

1:02:38Because a fresh salad that you make at home and you eat has polyphenols and antioxidants that are not processed. They come in your salad bowl and in your salad that you can compare. You can compare the efficacy and the health benefits of whole foods compared to something that is processed. What about protein powders? So protein powders is another interesting topic. And I think we are becoming very obsessed with protein powders because we are realizing that we don't have enough protein intake. The average adult in US does not have enough protein intake. So now the question is, how am I going to supplement that?

1:03:25For me, the safest and easiest way is with food. So make sure that you have 30 to 40 grams of protein intake with each meal. And I know there are various numbers out there, 1.6 to 2.2 grams per kilogram per day. But my recommendation, I try to simplify my recommendation. So I tell people that you're eating breakfast, look at your breakfast and see if there's any protein there. Look at your lunch, look at your dinner, your snacks. So try to consume enough protein with each meal and if you can with your snacks. Now going back to the protein powders, there have been studied and we know that some of them have heavy metals.

1:04:09Some of them are contaminated. So then again, the question is how can I assure the quality of that protein powder? A very recent study, I'm trying to remember the funding agency, it was part of the Clean Label Project. And they looked at, I believe, 134 different protein powders out there. And they reported that 47 % of them had heavy metals. So now the question about these heavy metals is that how much of heavy metals? Because if you look at Prop 65 in California, they almost recommend nothing. And that was a big, big critique of that work is that it was over-exaggerated the amount of heavy metals in this protein powder.

1:04:56But to me, if I am a consumer and I'm looking at the protein powder and there's a 47 % chance that this protein powder may have heavy metal, I would think twice. So I would again go back to my recommendation with protein powders, it is much safer to buy something that has the NSF stamp because NSF regulates sports and nutritional and dietary supplements that are used in sports. and protein powder, as you know, are heavily consumed among athletes. So I know that I'm starting to sound like a broken tape recorder, but go back to food. Consume your protein from whole foods and in your diet. And yes, every now and then we may need a protein shake.

1:05:46So I don't have anything against that. My sons consume them, but go for a good quality wine. Speaking of athletes, and I consider myself to be an amateur athlete and a dedicated worker, outer, I lift weights, et cetera, et cetera. Something I hear a lot about in fitness circles, but have never tried myself, and I don't actually even know really what it is, so maybe you can educate me, creatine. What's your take on creatine? Creatine is an emerging dietary supplement. A lot of people confuse it with a type of protein. They said, oh, right after workout, I have to take my creatine because this is going to be another protein I'm taking.

1:06:29It is not. Creatine is a dietary supplement. And again, here going back to the science, we've had really interesting studies on creatine. So if you are going to the gym and you're lifting and you want to improve the quality and the quantity of your muscle, taking creatine can be helpful. So the recommendation is, you know, after your workout, try to take three to five grams of creatin. And if you have a good kidney function, it is pretty safe. Now we have studies suggesting that creatin could also be good for cognition. It could be good for brain health. And there is a positive trend in these studies, but I think we need more.

1:07:14The best benefit with creatine when it comes to the impact on brain health was observed in postmenopausal women. But if you are an athlete and you're working out, taking creatine can be useful. Because I don't know how deep you want me to go into the mechanism of action of creatine, but it really helps the production of ATP in our muscle cells. And it also helps with the retention of water. So you may hear people saying that I started taking creatine and I gained weight. Well, the first one to two extra kilogram or four or five pounds of extra weight is because of the water retention in your muscles.

1:07:55This is not really a weight, unless you're also eating a lot of candies and sugary stuff when you exercise. And the last thing I want to say about creatine, because I just got this question actually yesterday. So it's really fresh on my mind that the type is important. So creating monohydrate is probably the one that you should consume because it's better absorbed. Another supplement that people are talking about a lot these days, I think this is a category of supplements, I think, peptides. I'm hearing a ton about peptides that are all over the internet. What are peptides and what's your take on them?

1:08:34If you have a good diet and you consume enough proteins, you probably don't need any extra amino acids and any extra peptides. There are a lot of claims suggesting that when you take peptides, you're going to have better elasticity in your skin, your hair, your nails. And I put peptides in the same category as I put collagen, that these studies have been very subjective. I mean, not very subjective, but semi-subjective because they use surveys and they look at your superficial skin, for instance, to say that if they work and if they don't work. And again, going back to the quality, if you are convinced that this peptide supplement is going to help you, at least go for the right quality.

1:09:24Make sure that the quality of the supplement is good. But the data is not very convincing. Okay, last thing to ask you about, although there are a million other things I could ask you about, but we don't have infinite time. Probiotics, live microorganisms that allegedly aid digestion. So probiotics and enzymes. Any evidence for these? So probiotics are also very popular and some people just take them on a daily basis. My recommendations on probiotics is that you have to work on your diet. If you want to have a good microbiota in our gut, probiotics are just going to offer a very temporary solution to a gut microbiota that needs to become healthy with our diet.

1:10:13So my recommendation is if you want to have a healthy gut microbiota, stay away from sugar, especially processed sugar or anything that has high amounts of sugar, and consume fruits and vegetables. That is how you have a healthy microbiota. Taking probiotics for very specific conditions could be helpful. For instance, if you are taking antibiotics, I highly recommend that you take a high-quality probiotics while you are taking that antibiotics. And I recommend that you start taking it on day one. And why do I recommend that? Because probiotics are going to offset the gastrointestinal side effects that, for instance, the antibiotic is going to cause.

1:10:59But taking probiotics on a daily basis is really not recommended. There are some specific diseases like ulcerative colitis and Crohn's disease that may require taking probiotics. But again, that's a conversation you need to have with your physician to make sure that you are taking the right one. Because for people, for instance, who are immunocompromised for various reasons, because they are taking drugs to prevent organ rejection and things like that, probiotics can actually be quite harmful. Again, you have to look at the quality. They can cause infections. So I highly, highly recommend, again, the conversation with the healthcare providers to choose the right type of probiotics and the specific disease that you are taking probiotics for.

1:11:50You have been very patient with my pesky questions. I really appreciate it. And I want to recommend that everybody check out Dr. Jafari's book. Again, it's called The Truth About Dietary Supplements, An Evidence-Based Guide to a Safer Medicine Cabinet. I will put a link in the show notes if you want to go buy it, which, again, I think would be a wise move if this is a subject you're interested in. But in closing, let me just say, Dr. Matab Jafari, thank you so much for taking so much time with me slash us. Oh, thank you. Thank you for having me. And thank you for the great questions.

1:12:31Thanks again to Dr. Jafari. Super interesting to talk to her. I've actually made some pretty significant changes since this conversation. Don't forget it's Sleep Week over at the 10 % Happier app. You can sign up at danharris.com. You'll get our truckload of new sleep meditations that we're adding this week. And if you sign up today, tomorrow on Tuesday, we're going to do a live session with Carl Lai on how to boost your sleep with meditation. Finally, thank you to everybody who worked so hard to make this show. Our producers are Tara Anderson and Eleanor Vasili. Our recording and engineering is handled by the great folks over at Pod People.

1:13:08Lauren Smith is our managing producer. Marissa Schneiderman is our senior producer. DJ Kashmir is our executive producer. And Nick Thorburn of the band Islands wrote our theme.

1:13:28This episode is brought to you by Progressive Insurance. Do you ever find yourself playing the budgeting game? Well, with the Name Your Price tool from Progressive, you can find options that fit your budget and potentially lower your bills. Try it at Progressive.com. Progressive Casualty Insurance Company and Affiliates. Price and coverage match limited by state law. Not available in all states.