Transcription
All right, part two. Imagine something so well studied, so safe, and so effective that scientists keep uncovering new benefits years after it made waves. It's not exotic. It's not locked away in some secret vault. It's something very cheap that almost anyone can use. And for those of us over age 60, its effect can be truly transformative.
Imagine giving your brain a nutrient that actually slips past the blood-brain barrier, walks straight into your brain, the control room, and starts turning off the neurotransmitters. But it's not just your brain. It's your entire body's energy, physical energy. Today, we are diving deep into one of the most powerful and misunderstood supplements out there, L-carnitine and its acetyl-L-carnitine version.
You can think of acetyl-L-carnitine as a fat shuttle that escorts the fat into the power plants in your muscles. And by teaching your muscles to lean more towards fat as fuel, carnitine can support endurance and help you go longer in training and smooth out the recovery afterwards. And now you may ask, if it helps you to burn fat, will it help you to lose weight? It can turn stored fat into usable power. Indeed, because meta-analyses show that people using carnitine supplements on top of diet and exercise lose a bit more weight, about two to four extra pounds compared to the placebo groups. But it's not a magical pill. It just nudges your metabolism in the right direction.
Now, should you take it? Not so quickly. Your gut bacteria can make this supplement into something very problematic. It's called TMAO. But worry not. I will guide you today exactly with a very special strategy I developed on how to overcome this issue and still get the benefits of acetyl-L-carnitine and L-carnitine.
Nature puts L-carnitine and acetyl-L-carnitine into mother's milk. So, what exactly is nature trying to achieve that? And of course, we're going to speak about how to take it specifically, because the way you're going to take it is going to have a dramatic effect on the impact I'm going to show you today.
So, carnitine is a natural nutrient the body makes. It appears in mother's milk. It appears in meat as well. The term carnitine suggests meat because "cara" is Latin for meat. The question is, do we actually need carnitine as a basic supplement for health, like a vitamin? And I think that we actually do need L-carnitine as a basic nutrient because if you look at L-carnitine, it actually behaves in many ways like B vitamins because it's essential for basic metabolism, especially fat metabolism. The body does produce some, but you still need small amounts from food or supplements, especially if you're vegetarian on a low-protein diet.
Very interesting. Vegetarians, if you're on a vegetarian diet and you don't get carnitine from food, the body actually increases the absorption rate in the gut. So, it tells you that the body actually craves carnitine from food. So, it tells me that the body actually has a minimal requirement for food. It's almost like a B vitamin. It's kind of essential in many ways, and especially essential if you're vegetarian because you really don't really get L-carnitine from food.
If I go back to the idea that the human body has specific transporters in your gut to absorb carnitine, and on a low-carnitine diet, the body upregulates these transporters. It begs the question, why would the body invest energy to create more carnitine transporters if it didn't care about absorbing it from food, right? It just would make more naturally, but no, it expects to get more from the outside. So, all this makes me think that we actually need to view that a bit more like B vitamins. Another clue that L-carnitine is really like a B vitamin is because nature puts L-carnitine in breast milk. So, it suggests that there is a basic human requirement for L-carnitine as well.
When you want to live longer, you want to burn fat and you want to help your body to burn fat. I think this is why nature puts L-carnitine in mother's milk to help the baby to burn fat despite the presence of sugar. But also, the body uses that naturally to increase fat burning during intense exercise. Why? Because the body knows it's not so easy for the muscles to burn a lot of fat. So, when you take a supplement, it's going to increase the levels in the blood, and then the muscles are going to take whatever they need. The muscles draw the carnitine inside and use it to burn fat. That's how it goes. And this also helps the muscles to stay young. So, it's going to help you with vitality, but also going to help the muscles to stay young as well.
The issue is that when we age, carnitine levels decline, and the capability of your muscles to burn fat goes down. So, by supplementing with L-carnitine, so it could be either L-carnitine or acetyl-L-carnitine, it supports the body's natural burning of fat that you eat during exercise. I think it's very good for moderate exercise because if you engage in aerobic exercise, you focus on zone 2 or zone 3, which is basically fat burning, then the muscles need a lot of carnitine to burn fat. If you do a lot of aerobics out of zone 2, zone 2, you know, is around 65 to 70% of the VO2 max. So, if you look at your maximum intensity capacity, you go to two-thirds of that, then fat burning is maximized. Over that, you begin to burn sugar. Okay. So, if you exercise, focus on the fat-burning range, or you do a lot of aerobic training, then you definitely want to consider L-carnitine.
You don't need to take it immediately before exercise. Take it in the morning. You can take it at night. It takes about two to three hours to be absorbed. If you're going to go to exercise, you just take carnitine before the exercise. It's not going to be ready for the body. You need to take it like two to three hours before. So, you can actually take that in the morning or even at night, and you're going to increase the reserves in the blood. The reserves stay one to two days.
There is another version that is called acetyl-L-carnitine, which is a bit better for the brain. The L-carnitine is slightly better for the muscles, but both of them are going to be helpful for exercise.
Does carnitine affect longevity? Yes. First of all, I've done aging tests, two aging tests. They showed that my muscles are really, really young, and I feel that when I compete in speed, when I compete against young people as well. Mechanistically, L-carnitine is supposed to help with longevity, and also there are some longevity studies showing increased lifespan in some, not in humans, and not in mammals, but in worms. So, the longevity data is kind of weak. It supports autophagy, supports fat burning, supports insulin sensitivity as well. All those things tend to help with longevity, and so it's a pro-longevity supplement for sure, but the data is not that strong that it's going to make you live longer.
Also worth noting that doctors have been using that with people with weak hearts, and it seems when the heart goes under extreme stress, L-carnitine may help the heart not get a heart attack in a certain situation. It can protect the heart under extreme stress. So, I think it's another thing that it would seem because some cardiologists I study from, they use that to prevent a secondary heart attack by allowing the heart make more energy. Makes sense? So, let's say the person has blocked arteries and therefore the heart can make less energy. It's starving for energy. L-carnitine maybe can help the heart make more energy and resist more stress and continue to pump strongly.
I've been taking L-carnitine, acetyl-L-carnitine specifically for 14 years. I started this in 2011 based on a recommendation by Dr. Ron Rosedale. In Dr. Ron Rosedale's perspective, one of the best ways to reduce aging is to help your body to burn fat. In November 2025, the study forced me to go back and review everything I know, everything we know about the supplement. Every fine-tuning is critical because we're going to compound that over time, right? Because we're going to take those supplements for decades. The dose, the timing, the separation of the supplements, with food, without food, the right brands, for example, all those things make a huge difference. I'm going to tell you what I do, but you can decide that based on your situation. This supplement doesn't make a lot of sense. I still take it myself, but we still have the main problem that I wanted to speak about today, which is not carnitine itself, but the fraction that is not absorbed.
90% of the carnitine, acetyl-L-carnitine over 80 milligrams, are not absorbed and they reach the gut bacteria. And the issue is that this 90% can get to the colon, and if you eat meat, the bacteria will convert that to TMAO. TMAO levels in the blood in humans are strongly associated with cardiovascular disease, vascular inflammation, and diabetes. And this is a debate that has been going on, I think, for like 10 to 15 years right now. Scientists have been trying to prove that it's a direct cause of cardiovascular disease and diabetes. My point is, when you think about the supplement, if you have chronic inflammation, if you have high APOB, if you have kidney issues, TMAO can become a problem, a toxic burden on your body. And when you think about it, it makes sense, you know, if you have a massive amount of inflammation, now you have a junk that the kidneys try to remove. They do not remove that. It floats in your blood. I mean, I can definitely see how it can inflame the situation. So, if you have an already inflamed situation, the kidneys cannot remove this garbage, you can definitely have a problem.
But it seems that TMAO itself is not the core villain. And also, you should know that fish have a lot of TMAO. When you eat fish, and fish is not associated with higher mortality, actually the opposite, it's actually associated with longevity. That's a good indication that probably TMAO is not a huge issue, if it is an issue. But still, we want to minimize TMAO and we want to increase absorption from the supplement. So, let's speak about the strategy. What's going to be the strategy to minimize TMAO and maximize L-carnitine activity and absorption?
One of the things that I try to see is what nature does. Nature puts in mother's milk both L-carnitine and acetyl-L-carnitine. Mostly it puts L-carnitine, but even nature sees the benefit of mixing these two. Maybe we can imitate that. So, the first question is, how much carnitine do babies receive from food? If I translate that to adults, nature provides the baby 100 up to 200 milligrams of carnitine per day. But nature splits that into multiple doses every three to four hours, right? So, this is very different from the typical one gram or 500 milligrams twice a day that I've been using.
What did I say in the beginning? 80 milligrams are going to be absorbed at a high rate, and after that, they're not going to be absorbed. So, when you consume these levels, you're not going to get much TMAO. In many ways, nature provides carnitine in a way that will not produce any TMAO anyhow, besides the fact that babies do not consume meat, so they're not going to have the gut microbiome anyhow. But what nature does really is great for maximal utilization and lowering TMAO.
There is no value, in my opinion, taking more than 100 milligrams at once because anything above 100 milligrams will have only 10% absorption. 90% is going to reach the colon, and if you eat meat and if you have bacteria that make TMAO, they're going to make everything into TMAO, then the kidneys would have to drop that into the urine.
Another issue that we have that was discovered in November 2025 is that it's not just the conversion by the bacteria. The kidneys try to maintain L-carnitine in the blood because they view that as a nutrient, but if you have too much, you're going to lose that via the urine because the kidneys would not be able to keep up with the levels in the blood. So, actually, having too much, too high a level in the blood of acetyl-L-carnitine is going to go to waste. So, there really is no benefit of consuming too much L-carnitine. You're just going to give more to the bacteria to make TMAO, and if you're going to get into the system, you're going to lose it by the urine. So, there is no benefit at all.
Another thing that we need to know about the best strategy is that I used to think that it's absorbed like an amino acid, very fast into your system, but it does not. Actually, the transporter in your gut, it takes two to three hours to fully absorb carnitine. Still carnitine. So, the first 80 milligrams of carnitine, it takes them two to three hours to be absorbed. And when you think about how often babies receive L-carnitine from milk, roughly every three hours. So, nature knows exactly what it's doing. So, practically, if you take one dose of L-carnitine, the second dose should be at least three to four hours after that. Because only then you're going to hit fresh, unsaturated transporters.
Besides, last year I've been taking one gram twice a day, so two grams a day. Last year I changed that to 500 milligrams. If I take everything that we know, my ideal daily regimen today is actually about 200 milligrams per day, 100 milligrams twice a day, morning and before bed. And theoretically, if I could get, if I could find a supplement, it does not exist, but if I could find a supplement that had 50 milligrams of carnitine and 50 milligrams of acetyl-L-carnitine, which is very different from what I've been doing over the last 14 years, it's way lower doses. The issue that we have is that no companies right now mix them and they do not provide these lower doses. They usually sell 500 milligrams per dose, and you can buy them, you know, in tablets, powders, in capsules.
Worth noting that when you speak about the dose, acetyl-L-carnitine is only about 80% carnitine by weight. So, the acetyl is 20%, and 80% is the L-carnitine. 500 milligrams of acetyl-L-carnitine is basically 400 milligrams of L-carnitine in terms of TMAO load.
The best way to take that, with food or without food? Absolutely on an empty stomach because L-carnitine is not easily absorbed. It competes with amino acids for transporters. Actually, lysine specifically can interfere with the transporters that absorb L-carnitine, and also some of the transporters for amino acids can utilize and absorb L-carnitine as well. So, there is a double benefit of taking L-carnitine on an empty stomach. I would take it at least 30 minutes before protein-containing food. It's okay to take it with fat. There is no problem because the fat is not going to interfere with the absorption. It's okay to take with avocado, for example, or with some fiber, it's fine, but I would not take it with protein.
Another question is, once a day or twice a day? Now, this is another thing that I didn't know, but I assumed that the body utilizes L-carnitine very fast. But in reality, acetyl-L-carnitine stays in your body more than a day, and L-carnitine actually stays more than two days in your system. That's what they found. So, in essence, what it means, if you take like 100 milligrams, let's say that you absorb 70 milligrams, right? Let's say out of these 70 milligrams, they're going to stay in your blood, in the system for about a day. So, you actually don't have to take it twice a day, but you want to take it twice a day to maximize the absorption. So, you don't really take it twice a day to refill the body's needs. You take it twice a day because it takes three hours to absorb the first dose, then you need another dose.
My preferred pair is actually 100 milligrams in the morning, 100 milligrams before sleep. In my opinion, the night dose has perfect spacing because what is going to happen when you take it at night? You're not going to eat any protein anytime soon, and it's going to take nine hours until the next dose. If you take a low dose, very little is going to reach the colon, so you're going to have the lowest TMAO production. Another reason I think it's beneficial to take it before sleep is because it supports fat burning. So, it makes sense, you know, to give your body some fat-burning support during the night. But it's really not a big deal. You can take it in the morning and take it another time in the mid-afternoon. Would it have a negative effect on sleep? And there is no negative effect on sleep from taking L-carnitine before sleep. So, I think for simplicity, it makes sense to take 100 milligrams in the morning and before sleep. Put it in water and drink. Other things you take before sleep, like magnesium, for example.
And this is a summary, and then we're going to go to the products. Both L-carnitine and acetyl-L-carnitine have value, but the effects are different. Ideal dose for me would be 50/50 twice a day, empty stomach, away from food, at least three to four hours between each dose. If you have kidney issues, if you have proven cardiovascular disease, you may need to think about the supplement. If you have inflamed arteries right now, it's up to you. I gave you the data, you can make a decision if it's worth it for you. I'm going to show you both L-carnitine and acetyl-L-carnitine. In my opinion, there is value to mix both of them. If you want to optimize, you can take 100 milligrams in the morning from this and 100 in the evening from the other one. You can actually mix, you can complete one product, finish the package, and then go to the other type.
One option is buying L-carnitine tablets. The benefits of tablets, you can actually break them down. So, this has 500. Yeah, this is 500 milligrams. So, if you can break that into four parts of the tablets, you can actually get about 100 milligrams. Technically, you can buy the 30 tablets. It's going to cost you five bucks. It's going to last you for a long time, for like two months if you're going to take it twice a day. So, that's one option, buying a tablet and breaking it down. Another option, now they sell 250. So, what you can do, one option, just take the 250 and assume that, you know, one 150 of these can become TMAO theoretically. Another option, you can open up the powder and put it in water and take the first half of the capsule in the morning and the second half at night. You can just open up the capsule and save the second half for later in the day.
For acetyl-L-carnitine, it's more difficult. This company sells tablets, so you can actually break down the tablet into small parts. As I mentioned, this is equivalent to 400 milligrams of L-carnitine. So, in essence, every fourth is going to give you exactly 100 milligrams, exactly what we want. Or you can buy this powder and just put the tip of a tiny teaspoon. Buy a super small spoon and just touch the tiny bit of the spoon with the powder. The downside is that you would not know exactly the dose. That will be the downside. But you know, if you're like me and you eat mostly a vegetarian diet and you do all those things, whatever I'm not going to be absorbed, very little is going to become TMAO, and my kidneys are going to remove that. So, I feel fine to take a bit of the powder as well. So, these are like the four products you can use. I myself try to figure out what's going to be the most comfortable for me. I think I'm going to mix this powder with this tablet as well. Maybe when I finish the powder, I'm going to go to the tablet to L-carnitine back and forth. I'm not really sure.
Okay. Do you have any questions about this supplement before we go to other questions?
Is acetyl-L-carnitine better? I think they both provide different benefits. It seems that acetyl-L-carnitine is better for the brain, slightly. They kind of have 80% benefits the same, but L-carnitine seems a bit better for mitochondria function, and acetyl-L-carnitine is definitely better for the brain. Like if somebody has the beginning of Alzheimer's, the beginning of cognitive issues, you know, age 60, 65, I feel it's going to be way better than L-carnitine. But because we speak about exercise, for exercise benefits, I think L-carnitine is slightly better.
Does empty stomach mean we can take it with a bucket load of other supplements? Yeah, exactly. The issue is protein. Protein prevents the absorption of L-carnitine. The protein is going to interfere with the absorption. Not all the other supplements are going to be an issue. So, yeah, you can take it with any other supplements that you want, basically, besides the protein supplements like collagen and whey protein that are going to reduce a bit the absorption.
In the research about carnitine, which amount did they use? You know, in animals, they use various amounts. In humans, usually 500 milligrams up to three grams. But remember that they usually do the studies for three months or something, and the problem with that is that you won't see the effect of lifelong TMAO. So, if you take somebody, you give them high-dose L-carnitine, you're going to get this 10% absorption right from the high dose, and that high dose is going to have an effect, but you're not going to protect yourself from TMAO. TMAO is not going to cause a problem in the study because studies, you know, three months, six months, one year, TMAO is not going to cause any problem. In animal studies, there was actually a study that showed that if you take too much acetyl-L-carnitine, you lose the longevity benefits. One study compared a moderate dose with three times the dose. Definitely, there was a loss of benefits with too much of a high dose. What I show you today is quite creative. I mean, they all started with 500 milligrams, and then they found most of it becomes TMAO. But what about the long-term effect of TMAO? Do they measure that? They don't measure that. So, the study is incomplete. I mean, it's like the 80/20%. The first 20% of absorption is going to give the most amount of benefits. Anyhow, I'm absolutely sure about that. Some supplements like acetyl-L-carnitine seem to have a lot of the benefits coming when you take a high dose. With L-carnitine, it seems like you're going to get most of the benefits with the first absorption level, and this is it. So, all directions go in the lower dose twice a day. I mean, everything I've seen, nothing suggests that a higher dose is going to give any more benefit. Let's say that you take like one gram three times a day. You're probably going to get maybe 5% more benefits from L-carnitine theoretically. And also, remember what I said in the beginning, even if you absorb more, you're going to lose that in the urine because the kidneys would not be able to maintain that in the blood. There is no perspective I look at that makes sense to take a high, high dose of carnitine. It just doesn't make any sense. More potential TMAO, you're going to lose more in the kidneys in the urine, and you're not going to get more fat-burning benefits.
About taking acetyl-L-carnitine with collagen together? Collagen is a powder, so it's going to compete. It's going to reduce absorption of carnitine for sure. Absolutely. So, I would not take them together. You're still going to get some absorption, but it's going to be lower. And if you care about TMAO, anything that you do not absorb is going to reach the bacteria, and you give them the option to make TMAO. So, it's up to you. You're still going to absorb. I mean, nature puts that in milk, and we absorb L-carnitine via meat as well, but the research is quite consistent that L-carnitine is absorbed best on an empty stomach, 30 minutes away from any protein.
Kaz asks, so when is the best time to take collagen? If we take L-carnitine first thing and last thing in the day, just wait 30 to 40 minutes before you take collagen. Take the L-carnitine in the morning, wait 30 to 40 minutes, then consume any protein that you want. I assume that most of you don't eat protein before you go to sleep, right? So, I think taking the second dose before you go to sleep is good.
How long after we eat other proteins? For example, how long after dinner can we should wait before we take carnitine? I would say two to three hours is safe. If it's a fast protein, then maybe you can wait maybe faster. I mean, maybe like if it's collagen, maybe one hour is fine. But if you had red meat or something that takes your body a lot of time to digest, then red meat may even need three hours, you know, because it's very slow to digest. So, it depends on the digestion speed of the protein as well.
And another question, which supplements can be taken together? For example, L-carnitine, can I take them together with ALA? Yeah, absolutely. In fact, they've done a study that shows that acetyl-L-carnitine actually increases a bit because it helps the mitochondria become more active. It increases some oxidative stress, and alpha-lipoic acid actually synergizes with L-carnitine. So, if you're going to see some companies actually sell L-carnitine with lipoic acid. Also, you can take it with L-glycine as well. Even though glycine is an amino acid, it will not interfere with carnitine. Yeah. The issue is protein, not supplements. I cannot think of any supplement that could interfere with that. If you take lysine as a powder form, it's going to cause you problems.
So, this was just one supplement. Now you can see the complexity behind every supplement that you take. The routine, the avoidance of the side effects, and all of that needs to be updated as new research comes out. Because this video was produced after a November 2025 human study on L-carnitine. Now, if you are overwhelmed by the amount of research and the complexity of supplements and want a simple guide, you may want to consider the following. If you want to stop shooting arrows in every direction without knowing if you're actually aiming right, you want to understand on your own and get practical steps organized and simplified in one place, so it's going to be easy for you to apply. I was in your exact situation. So, I do understand. This is exactly why I created a new course which organizes and simplifies all the actionable steps into one place that can be done very quickly. Discover how at wellresiah.com/time.