What’s Taurine and Why Do We Care? (Part 2)

We know taurine abundance decreases during aging, and a reversal of this decline through taurine supplementation increases the healthspan and lifespan in mice and worms, and health in monkeys. So, this means taurine deficiency is a driver of aging in these species. To test whether taurine deficiency is a driver of aging in humans too, long-term, well-controlled taurine supplementation trials that measure human healthspan and lifespan as outcomes are required. Why haven’t these happened already? You know why. As a naturally occurring substance, taurine cannot be exploited through a commercial patent. You can buy pure taurine powder literally by the bucket at hardly a penny per gram. So, who’s going to fund studies on it?

In population studies, higher blood taurine levels are associated with less obesity and a lower prevalence of type 2 diabetes. But when put to test, as reviewed in this 2020 meta-analysis of randomized controlled trials, taurine supplementation had no significant effect on blood sugar control, LDL cholesterol, or body weight––though it did drop blood pressures and triglycerides a few points, at a daily dose of half a gram to six grams a day between 15 days and six months. A 2024 systematic review and meta-analysis of randomized controlled trials found the same small blood pressure and triglycerides benefit, as well as a small six-point drop in fasting blood sugars, though none of those few trials on people with diabetes showed that blood pressure benefit––though it did help their blood sugars.

Taurine can also slow our heart rate by three or four beats per minute, which is considered a good thing, and in addition to lowering blood pressures, it can improve heart muscle function in patients with heart failure. What about artery function? People with type 1 diabetes were given 500 mg of taurine three times a day for two weeks, and researchers saw a significant improvement in their artery function. Those with type 1 diabetes start out with reduced artery function compared to healthy controls, and giving them a placebo doesn’t seem to help. But the taurine seemed to elevate their artery function closer to healthy levels.

What about improving artery function in people without diabetes? In this study of individuals with prehypertension—about 130 over 80—who took about the same amount, 1.6 g a day for 12 weeks, they got the same blood pressure benefit seen in the other trials, and, importantly, improvement in artery function compared to placebo.

What about effects on inflammation and oxidation? Taurine can decrease the levels of c-reactive protein, a marker of oxidative stress, though it doesn’t appear to have much effect on some other markers of inflammation. So, okay, some modest effects, but there is a substantial mismatch between the strong scientific foundation supportive of the health benefits of taurine in animal studies, and the quality of clinical trials and their outcomes in assessing the efficacy of taurine in human health.

What’s the harm in taking it, though? It’s cheap and easy to find. A one-gram dose would cost as little as a penny a day. Most Americans are getting about 150 mg a day in their diet, mostly from meat. We make taurine ourselves, and so do many of the animals we eat. In fact, our realization that we made so much on our own came from studies of vegans who had taurine levels that were not significantly different from those eating meat, though they were about 15 percent lower. A subsequent study found the taurine levels of vegans were more like 20 percent lower than meat eaters, which did reach statistical significance. The clinical implications of reduced blood taurine levels in vegans are not known. Our ability to make taurine is supported by the fact that taurine deficiency has never been found in vegetarians, but just because vegan levels aren’t deficient doesn’t mean they are necessarily optimal.

Taurine is considered nonessential in adults because it can be readily synthesized within our own bodies—though infants may need to get it in breast milk until they can ramp up their own synthesis. But can adults make enough for optimal health, especially as we get older and all our levels decline? Why do our levels even decline as we age? It’s not just that because we may be getting less in our diet, since if you get none in your diet, your levels may only be like 20 percent lower, but levels over a lifespan decline by about 80 percent, suggesting we lose some of our capacity to churn it out.

Taurine has been envisioned as a longevity vitamin, meaning it isn’t like an actual vitamin-vitamin, where we die if we don’t get it. But even though we make it, we may also need to get some in our diet to optimize metabolism.

In a review of what clinicians might want to discuss with their patients on a plant-based diet who are suffering from some kind of problem, are these conditionally essential nutrients, where under normal conditions, they can be produced in our body in sufficient amounts, but something may interfere with synthesis, or conditions may arise where we may need more. Taurine is included in this list, as is carnitine, another compound found in meat that we can make on our own.

Imagine if people started taking carnitine supplements, thinking why not? What harm can it do? Of course, we now know that carnitine is one of the things we try to avoid in meat, because it turns into TMAO and may increase the risk of heart disease, kidney disease, and many of our other leading killers. Indeed, if you give people carnitine supplements, their TMAO levels shoot up; so, might that be a precautionary tale when it comes to taurine?

Take arginine, for example. It’s another non-essential amino acid in adults that has a variety of functions other than being part of proteins, including delaying the aging senescence of arterial lining cells. Animal studies have shown all sorts of heart-healthy benefits of arginine supplementation, including improved artery function and inhibition of atherosclerotic plaque, just like taurine. So, reviews like these studies strongly support favorable cardiovascular effects accruing from L-arginine supplementation based on short-term studies, just like taurine, but long-term treatment with L-arginine actually accelerates the aging process in human artery lining cells.

Did this paradoxical effect cause any actual problems?

Short-term supplementation showed an improvement in artery function. In contrast, long-term therapy with arginine supplementation did not improve artery or heart function. Instead, it led to premature death.

In our next story, we look at the downsides of taurine supplementation.

Taurine is an ingredient in some so-called energy drinks, which some people consume to improve physical performance, although there is little evidence that taurine per se exerts any beneficial effects in healthy individuals or animals without taurine depletion. But that was written before this seminal study, published in one of our most prestigious scientific journals, showed that taurine supplementation starting in middle-age can significantly improve the healthspan and lifespan of a number of different animals.

Now, not all animal studies have shown benefit. Lifelong taurine supplementation induced retardation of learning in mice, for example, and low doses of taurine significantly enhanced lung tumor growth in mice, which led the authors to suggest that lung cancer patients may want to stay away from drinks with taurine.

You probably wouldn’t want to consume too much taurine if you have kidney failure either, since taurine levels are normally regulated by our kidneys. The acute symptoms of taurine overload, mainly dizziness, were relatively mild and rapidly disappeared after stopping taurine, but researchers suggested there should be warning-type labels on beverages containing taurine to caution patients with kidney failure from drinking them.

Similarly, patients who have bleeding disorders may not want to take taurine since it might thin our blood. Psoriasis patients may also want to steer clear, as taurine evidently causes a predictable intense itching response that can last a day or two, making skin lesions worse. It even caused the same reaction in psoriasis patients in remission.

Pregnant and lactating women are pretty much encouraged to stay away from any and all supplements not specifically prescribed for pregnancy. Similarly, individuals with specific health conditions, such as bipolar disorder, epilepsy, or kidney problems may want to be cautious. The only bipolar problem I could find were a few case reports of mania blamed on Red Bull. That would make me manic too! But of course, Red Bull has more than just taurine. Caffeine alone may do it.

The epilepsy concern may have to do with taurine inhibiting detoxifying enzymes in the liver that are responsible for breaking down many commonly used drugs, including anti-seizure drugs. It could also be because of adverse reactions reported by some patients with epilepsy who took 1.5 grams a day, including nausea, headache, dizziness, nose-bleed, and mild walking disturbances, but the epilepsy seems incidental. That may just be what may sometimes be seen at higher doses. Potential side effects of excessive consumption of taurine supplements beyond recommended doses include gastrointestinal disturbances (such as nausea, vomiting, and diarrhea) and neurological symptoms (like dizziness, tremors, and headaches). What are the recommended doses?

A proposed tolerated upper safety limit based on human clinical trials is up to three grams a day, but the longest trial at that dose was only up to four months. In my last video, I talked about an analogy with another conditionally non-essential amino acid called arginine that similarly looked good in short-term trials, but by six months appeared to be killing people—oopsie—so, the study was shut down.

So, who knows if the supposed safe level of three grams a day is actually safe? The dose used in that promising animal study might be equivalent to dosing people with even more than that, and higher doses aren’t necessarily better. In this study on inflammation and oxidative stress, the lower doses—three grams or less—appeared to work better. The thought is that high doses of taurine could downregulate our own synthesis of taurine. Why would that be a problem? Well, our body makes taurine from another amino acid called cysteine; so, if we’re no longer churning out taurine, that may cause our levels of cysteine to build up—at least, that’s what happens in mice. And that might be bad, because chronically high levels of cysteine have been closely associated with a whole list of disease states including rheumatoid arthritis, Parkinson’s, Alzheimer’s, lupus, cardiovascular disease, and adverse pregnancy outcomes. On the other hand, taurine may inhibit our absorption of another amino acid called methionine, since taurine and methionine share the same absorption transporter through our intestinal lining. That would be presumed to be a good thing, since lowering methionine intake is considered a feasible strategy against chronic and ageing-related diseases, as I discussed in How Not to Age.

And finally, the animal study didn’t address the impact of taurine dietary supplementation on the gut microbiome, which I’ll cover, next.

The remarkable trial showing that taurine supplementation improved the lifespan and healthspan of animals used doses that may far exceed the recommended safe consumption limits in humans. At the press conference, the corresponding author said that they would not recommend people to start taking taurine supplements to try to preserve health or slow aging. Not only do we have no human studies showing that kind of benefit, but we don’t even know the potential risks, since we don’t have large long-term human safety trials. In my last video, I talked about those who might be particularly sensitive to taurine, and what happens, at least in the short term, if we exceed recommended intakes. If, after careful consideration, you still want to give it a try, what source, dose, and frequency might be best?

In terms of frequency, the bump in our bloodstream only lasts about six hours; so, we’d presumably want to take split doses to maintain higher levels––for example, three times a day, like at every meal.

What dose? Well, just for context, most people get between 40 and 400 mg a day through their diet; so, that’s like a normal typical daily dose.

If our goal is to restore youthful levels, we’d want to bump up our levels from around the 50-micromole range to maybe the 100 or 200 range.

In this study, researchers gave people 1.66 grams twice a day, shooting up plasma levels to a thousand; yet, at the end of the week, there was no change in levels in the muscle, based on muscle biopsies. The body didn’t seem to care what was happening in the blood—it kept the tissue levels stable. In contrast, when rats are given taurine, the levels of taurine in their muscles go up. So, maybe taurine is like the NAD-booster debacle? You can rewatch my webinar for a recap, but remember how NAD also declined with age, and restoration of youthful levels with supplements caused all these amazing benefits in lab animals. So, a gazillion-dollar NAD supplement industry was born. But, when finally put to the test in people, they totally flopped—and no wonder. In rodents, these supplements actually boosted NAD levels in their tissues, but we’re not rodents, and the supplements all failed to raise levels in our muscles.

So, maybe when we have human trials on taurine, they’ll also fail in the same way, but maybe not. For those who don’t want to wait, what dose should we shoot for? We really have no idea, but from all the human trials that have been done, the most commonly used dose in the blood pressure-lowering trials, which is probably the best demonstrated benefit that also best lowers oxidative stress and inflammation is about 1.5 grams a day; so, that would be 500mg three times a day. Okay, that’s the dose and the frequency, but what’s the best source? That’s exactly what I’ll cover, next.