Too much or too little testosterone?

One Man’s Saw Palmetto Is Another Woman’s Serenoa Repens… Learn about the benefits of saw palmetto, a herbal supplement that can increase testosterone levels in men and limit hair loss in both men and women.
A cartoon highlighting the effects of too much or too little testosterone with the words "spotlight" and "saw palmeto.

One Man’s Saw Palmetto Is Another Woman’s Serenoa Repens…

Today we’re going to look at saw palmetto. So, first:

What is it?

Saw palmetto is a type of palm native to the southeastern United States. Its scientific name is “Serenoa repens”, so if that name appears in studies we cite, it’s the same thing. By whichever name, it’s widely enjoyed as a herbal supplement.

Why do people take it?

Here’s where it gets interesting, because people take it for some completely opposite reasons…

Indeed, searching for it on the Internet will cause Google to suggest “…for men” and “…for women” as the top suggestions.

That’s because it works on testosterone, and testosterone can be a bit of a double-edged sword, so some people want to increase or decrease certain testosterone-related effects on their body.

And it works for both! Here be science:

  • Testosterone (henceforth, “T”) is produced in the human body.
    • Yes, all human bodies, to some extent.
  • An enzyme called 5-alpha-reductase converts T in to DHT (dihydrogen testosterone)
  • DHT is a much more potent androgen (masculinizing agent) than T alone, such that its effects are often unwanted, including:
    • Enlarged prostate (if you have one)
    • Hair loss (especially in men)
    • New facial hair growth (usually unwanted by women)
      • Women are more likely to get this due to PCOS and/or the menopause

To avoid those effects, you really want less of your T to be converted into DHT.

Saw palmetto is a 5α-reductase inhibitor, so if you take it, you’ll have less DHT, and you’ll consequently lose less hair, have fewer prostate problems, etc.

Read: Determination of the potency of a novel saw palmetto supercritical CO2 extract (SPSE) for 5α-reductase isoform II inhibition using a cell-free in vitro test system

^The above study showed that saw palmetto extract performed comparably to finasteride. Finasteride is the world’s main go-to prescription drug for treating enlarged prostate and/or hair loss.

See also: Natural Hair Supplement: Friend or Foe? Saw Palmetto, a Systematic Review in Alopecia

Hair today… Growing tomorrow!

So, what was that about increasing T levels?

Men usually suffer declining T levels as they get older, with a marked drop around the age of 45. With lower T comes lower energy, lower mood, lower libido, erectile dysfunction, etc.

Guess what… It’s T that’s needed for those things, not DHT. So if you block the conversion of T to DHT, you’ll have higher blood serum T levels, higher energy, higher mood, higher libido, and all that.

Read: Standardized Saw Palmetto Extract Directly and Indirectly Affects Testosterone Biosynthesis and Spermatogenesis

(the above assumes you have testicles, without which, your T levels will certainly not increase)

Saw Palmetto Against Enlarged Prostate?

With higher DHT levels in mid-late life, prostate enlargement (benign prostatic hyperlasia) can become a problem for many men. The size of that problem ranges from urinary inconvenience (common, when the prostate presses against the bladder) to prostate cancer (less common, much more serious). Saw palmetto, like other 5α-reductase inhibitors such as finasteride, may be used to prevent or treat this.

Wondering how safe/reliable it is? We found a very high-quality fifteen-year longitudinal observational study of the use of saw palmetto, and it found:

❝The 15 years’ study results suggest that taking S. repens plant extract continuously at a daily dose of 320 mg is an effective and safe way to prevent the progression of benign prostatic hyperplasia.❞

Read: 15 years’ survey of safety and efficacy of Serenoa repens extract in benign prostatic hyperplasia patients with risk of progression

Want a second opinion? We also found a 10-year study (by different researchers with different people taking it), which reached the same conclusion:

❝The results of study showed the absence of progression, both on subjective criteria (IPSS, and QoL scores), and objective criteria (prostate volume, the rate of urination, residual urine volume). Furthermore, patients had no undesirable effects directly related to the use of this drug.❞

  • IPSS = International Prostate Symptom Score
  • QoL = Quality of Life

Read: The results of the 10-year study of efficacy and safety of Serenoa repens extract in patients at risk of progression of benign prostatic hyperplasia

But wait a minute; I, a man over the age of 45 with potentially declining T levels but a fabulous beard, remember that you said just a minute ago that saw palmetto is used by women to avoid having facial hair; I don’t want to lose mine!

You won’t. Once your facial hair follicles were fully developed and activated during puberty, they’ll carry on doing what they do for life. That’s no longer regulated by hormones once they’re up and running.

The use of saw palmetto can only be used to limit facial hair if caught early—so it’s more useful at the onset of menopause, for those who have (or will have) such, or else upon the arrival of PCOS symptoms or hirsuitism from some other cause.

Take The Test!

Do you have a prostate, and would like to know your IPSS score, and what that means for your prostate health?

Take The Test Here!

(takes 1 minute, no need to pee or go probing for anything)

Bottom Line on Saw Palmetto

  • It blocks the conversion of T into DHT
  • It will increase blood serum T levels, thus boosting mood, energy, libido, etc in men (who typically have more T, but whose T levels decline with age)
  • It will decrease DHT levels, thus limiting hair loss (especially in men) and later-life new facial hair growth (especially in women).
  • It can be used to prevent or treat prostate enlargement
  • Bonus: it’s a potent antioxidant and thus reduces general inflammation (in everyone)

Want To Try Saw Palmetto?

We don’t sell it (or anything else), but for your convenience…

Click here to check out saw palmetto on Amazon!

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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!