L-Theanine: What’s The Tea?

L-Theanine: The Tea’s Secret Ingredient. L-theanine, an amino acid found in tea, offers numerous benefits including increased mental focus, relaxation without drowsiness, stress relief, and other potential health advantages.
Explore the myriad benefits of L-theanine found in tea.

L-Theanine: What’s The Tea?

We’ve touched previously on l-theanine, when this newsletter was new, and we had only a few hundred subscribers and the carefully organized format wasn’t yet what it is today.

So now it’s time to give this potent dietary compound / nutritional supplement the “Monday Research Review” treatment…

What is it?

L-theanine is an amino acid found in tea. The human body can’t produce it, and/but it’s not essential for humans. It does have a lot of benefits, though. See for example:

L-Theanine as a Functional Food Additive: Its Role in Disease Prevention and Health Promotion

How does it work?

L-theanine works by moderating and modulating the brain’s neurotransmitters.

This sounds fancy, but basically it means: it doesn’t actually add anything in the manner of a drug, but it changes how we use what we have naturally.

What does it do? Read on…

It increases mental focus

It has been believed that l-theanine requires the presence of caffeine to achieve this (i.e., it’s a combination-only effect). For example:

The combination of L-theanine and caffeine improves cognitive performance and increases subjective alertness

But as it turns out, when a group of researchers actually checked… This isn’t true, as Foxe et al. write:

❝We asked whether either compound alone, or both in combination, would affect performance of the task in terms of reduced error rates over time, and whether changes in alpha-band activity would show a relationship to such changes in performance. When treated with placebo, participants showed a rise in error rates, a pattern that is commonly observed with increasing time-on-task, whereas after caffeine and theanine ingestion, error rates were significantly reduced. The combined treatment did not confer any additional benefits over either compound alone, suggesting that the individual compounds may confer maximal benefits at the dosages employed❞

See: Assessing the effects of caffeine and theanine on the maintenance of vigilance during a sustained attention task

It promotes a calmly wakeful feeling of serenity

Those are not words typically found in biopharmaceutical literature, but they’re useful here to convey:

  • L-theanine promotes relaxation without causing drowsiness
  • L-theanine promotes mental alertness without being a stimulant

Here is where l-theanine really stands out from caffeine. If both substances promote mental focus, but one of them does it by making us “wired” and the other does it while simultaneously promoting calm, it makes the choice between them clearer!

Read more: L-theanine, a natural constituent in tea, and its effect on mental state

It relieves stress and anxiety

Building on from the above, but there’s more: l-theanine relieves stress and anxiety in people experiencing stressful situations, without any known harmful side effects… This is something that sets it apart from a lot of anxiolytic (antianxiety) drugs!

Here’s what a big systematic review of clinical trials had to say:

Theanine consumption, stress and anxiety in human clinical trials: A systematic review

L-theanine has other benefits too

We’ve talked about some of the most popular benefits of l-theanine, and we can’t make this newsletter too long, but research also suggests that it…

If you’re interested in this topic, we recommend also reading our previous article on l-theanine—pardon that we hadn’t really nailed down our style yet—but there’s a bunch of useful information about how l-theanine makes caffeine “better” in terms of benefits. We also talk doseage, and reference some other studies we didn’t have room to include today!

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  • Stop Cancer 20 Years Ago

    Dr. Jenn Simmons shares vital tips on preventing cancer and inflammation, advocating for lifestyle changes and proactive health management at any age.

    Get Abreast And Keep Abreast

    This is Dr. Jenn Simmons. Her specialization is integrative oncology, as she—then a breast cancer surgeon—got breast cancer, decided the system wasn’t nearly as good from the patients’ side of things as from the doctors’ side, and took to educate herself, and now others, on how things can be better.

    What does she want us to know?

    Start now

    If you have breast cancer, the best time to start adjusting your lifestyle might be 20 years ago, but the second-best time is now. We realize our readers with breast cancer (or a history thereof) probably have indeed started already—all strength to you.

    What this means for those of us without breast cancer (or a history therof) is: start now

    Even if you don’t have a genetic risk factor, even if there’s no history of it in your family, there’s just no reason not to start now.

    Start what, you ask? Taking away its roots. And how?

    Inflammation as the root of cancer

    To oversimplify: cancer occurs because an accidentally immortal cell replicates and replicates and replicates and takes any nearby resources to keep on going. While science doesn’t know all the details of how this happens, it is a factor of genetic mutation (itself a normal process, without which evolution would be impossible), something which in turn is accelerated by damage to the DNA. The damage to the DNA? That occurs (often as not) as a result of cellular oxidation. Cellular oxidation is far from the only genotoxic thing out there, and a lot of non-food “this thing causes cancer” warnings are usually about other kinds of genotoxicity. But cellular oxidation is a big one, and it’s one that we can fight vigorously with our lifestyle.

    Because cellular oxidation and inflammation go hand-in-hand, reducing one tends to reduce the other. That’s why so often you’ll see in our Research Review Monday features, a line that goes something like:

    “and now for those things that usually come together: antioxidant, anti-inflammatory, anticancer, and anti-aging”

    So, fight inflammation now, and have a reduced risk of a lot of other woes later.

    See: How to Prevent (or Reduce) Inflammation

    Don’t settle for “normal”

    People are told, correctly but not always helpfully, such things as:

    • It’s normal to have less energy at your age
    • It’s normal to have a weaker immune system at your age
    • It’s normal to be at a higher risk of diabetes, heart disease, etc

    …and many more. And these things are true! But that doesn’t mean we have to settle for them.

    We can be all the way over on the healthy end of the distribution curve. We can do that!

    (so can everyone else, given sufficient opportunity and resources, because health is not a zero-sum game)

    If we’re going to get a cancer diagnosis, then our 60s are the decade where we’re most likely to get it. Earlier than that and the risk is extant but lower; later than that and technically the risk increases, but we probably got it already in our 60s.

    So, if we be younger than 60, then now’s a good time to prepare to hit the ground running when we get there. And if we missed that chance, then again, the second-best time is now:

    See: Focusing On Health In Our Sixties

    Fast to live

    Of course, anything can happen to anyone at any age (alas), but this is about the benefits of living a fasting lifestyle—that is to say, not just fasting for a 4-week health kick or something, but making it one’s “new normal” and just continuing it for life.

    This doesn’t mean “never eat”, of course, but it does mean “practice intermittent fasting, if you can”—something that Dr. Simmons strongly advocates.

    See: Intermittent Fasting: We Sort The Science From The Hype

    While this calls back to the previous “fight inflammation”, it deserves its own mention here as a very specific way of fighting it.

    It’s never too late

    All of the advices that go before a cancer diagnosis, continue to stand afterwards too. There is no point of “well, I already have cancer, so what’s the harm in…?”

    The harm in it after a diagnosis will be the same as the harm before. When it comes to lifestyle, preventing a cancer and preventing it from spreading are very much the same thing, which is also the same as shrinking it. Basically, if it’s anticancer, it’s anticancer, no matter whether it’s before, during, or after.

    Dr. Simmons has seen too many patients get a diagnosis, and place their lives squarely in the hands of doctors, when doctors can only do so much.

    Instead, Dr. Simmons recommends taking charge of your health as best you are able, today and onwards, no matter what. And that means two things:

    1. Knowing stuff
    2. Doing stuff

    So it becomes our responsibility (and our lifeline) to educate ourselves, and take action accordingly.

    Want to know more?

    We recently reviewed her book, and heartily recommend it:

    The Smart Woman’s Guide to Breast Cancer – by Dr. Jenn Simmons

    Enjoy!