Saw palmetto (Serenoa repens) is an herb that is increasing in popularity for hormonal regulation, specifically for the benefits it may have for high testosterone.
Native to the US, this herb has been traditionally used by Indigenous people who first discovered its benefits centuries ago.
Saw palmetto has anti-androgenic properties, meaning it can help mitigate the negative effect of testosterone and its potent metabolite, DHT. Of course, testosterone has its benefits (yes, even in people with a uterus), but too much of it may lead to unwanted symptoms like:
- Oily skin
- Hair loss
- Excess body hair
- Irritability or aggression
- Increased body odour
- Decreased breast size
- Increased muscle mass
In this article, we’ll look at what saw palmetto is, how it works to balance testosterone, and whether this traditional herb might be useful for you.
What is Saw Palmetto
Saw palmetto is derived from the ripe berry-like fruit of the American Dwarf Palm, which is native to the US and commonly found on the East Coast. As a supplement, you can find it in capsule, tablet, or liquid extract form.
Indigenous people of North America used this herb for reproductive concerns, as an aphrodisiac, and as a sedative.
Learning from the wisdom of our ancestors, modern science sought to understand how this herb specifically works in improving hormone health.
Here’s what they found.
What Does Saw Palmetto Do?
Saw palmetto has the potential to block the conversion of testosterone to its more active form, dihydrotestosterone (DHT). It is the excessive levels of DHT that lead to some of the symptoms of high testosterone, like hair loss and hirsutism.
Let me explain in a little more detail how this all works.
How Saw Palmetto Regulates Testosterone Levels
It is through the action of 5 alpha-reductase that testosterone is converted to DHT.
High levels of DHT are responsible for symptoms like acne, excess body hair (hirsutism), oily skin, and irreversible hair loss. This is why saw palmetto is often recommended for managing symptoms of polycystic ovarian syndrome (PCOS).
Saw palmetto may also increase the breakdown of DHT making it less available to stimulate hair and other tissues.
Additionally, saw palmetto has been shown to decrease tissue uptake of androgens, both testosterone and DHT. So while there may still be circulating androgens present, they have less of an ability to stimulate tissues than they would otherwise.
Overall, saw palmetto can inhibit the conversion of testosterone to DHT, break down DHT, and prevent the tissues from using some of the DHT that is available.
Does Saw Palmetto Regrow Hair?
Androgenetic alopecia is a condition that causes hair loss and balding. This form of hair loss is caused by androgens, specifically DHT. While often referred to as “male pattern hair loss,” androgenic alopecia can happen in anyone with the genetic predisposition.
Among women, this type of hair loss is known as female pattern hair loss and is quite common, although understandably not talked about. Among white women the prevalence of FPHL may be as high as 19%. FPHL prevalence increases with age with one study showing that 38% of women above the age of 70 who presented to a dermatology clinic for non-hair loss related symptoms experienced FPHL.
In Black women the primary cause of hair loss is due to an inflammatory disorder which leads to scarring of the follicle and permanent hair loss known as central centrifugal cicatricial alopecia (CCCA). They are also prone to traction alopecia, which is caused by hair styles that pull too tightly on the follicle. When surveyed 40.9% of Black women reported hair loss with less than 10% of them receiving a formal diagnosis.
Compared to white women, Hispanic women have been shown to report higher incidences of alopecia areata.
Losing some hair is a completely normal part of your hair’s lifecycle. But if you find yourself losing excessive amounts of hair, or your hair is thinning significantly, DHT could be at play.
DHT acts directly on the hair follicle by causing it to shrink, which is referred to as miniaturization. This makes the hair thinner and weaker. The hair strand then completes its life cycle early and falls out. Excessive DHT could lead to an increase in hair loss and prevent the regrowth of new hair.
Saw palmetto supplementation may reduce hair loss by decreasing 5-alpha reductase activity and therefore, the conversion of testosterone to DHT. Applying products, such as shampoo, containing saw palmetto directly to the scalp may also help.
Additionally, saw palmetto may also prevent the hair follicle from taking up DHT, which can prevent damage.
Some studies show that patients who used saw palmetto felt their hair growth, density, and thickness increased.
While saw palmetto may be beneficial for hair loss, it is important to note that this is not the same kind of hair loss experienced postpartum. As such, it is not indicated for postpartum hair loss.
Is Saw Palmetto Good For Acne?
Testosterone (and DHT) can contribute to acne breakouts. That’s why you are more likely to experience acne around puberty, your period or mid-cycle, and menopause — times when your hormones fluctuate most.
DHT is responsible for the increase in sebum production (oil) that can clog up your pores leading to acne.
Given saw palmetto’s ability to curb the overproduction of DHT via 5-alpha reductase activity, it may be beneficial in those who suffer from acne. This is another reason why saw palmetto is often recommended for those with PCOS.
As an added benefit, saw palmetto has anti-inflammatory properties, which could reduce that red, inflamed quality of acne.
Is Saw Palmetto Helpful for PCOS?
Polycystic Ovarian Syndrome is a metabolic condition linked to inflammation and insulin resistance. The condition can present with a variety of hormonal imbalances, including elevated testosterone and subsequent DHT.
As we know, saw palmetto can limit DHT production, but it can also increase its breakdown, helping to remove excess DHT already in the body. This may reduce acne, hirsutism (coarse hair growth on the chin, chest, abdomen), hair loss, and other symptoms related to excess testosterone associated with PCOS.
Furthermore, saw palmetto can balance another important hormone, prolactin. Prolactin is responsible for the cyst formation in those who experience PCOS. It is also a hormone that suppresses follicle maturation (egg development) and ovulation. Prolactin is in part responsible for irregular cycles.
Finally, the anti-inflammatory properties of saw palmetto may help reduce the pelvic pain, inflammation, and bloating experienced by many PCOS sufferers.
Saw Palmetto May Help Lower Inflammation
Saw palmetto has been shown to decrease inflammatory markers.
Inflammatory markers are typically found on lab investigations and signify the presence of inflammation in the body. Decreasing inflammatory markers usually indicate decreasing inflammation.
It may also improve chronic pelvic pain syndrome.
For a deep dive into how inflammation and PCOS are linked, check out my article PCOS, Inflammation, and Insulin.
May Improve Urinary Tract Health
Saw palmetto’s anti-androgenic properties may support men’s urinary health. But, its potential to improve women's urinary function is unlikely to be linked to the anti-androgenic properties of the herb.
Its support of urinary tract health appears to be more related to its anti-inflammatory properties. While it can be beneficial in urinary tract health, it is not considered a first line herb for this purpose.
Check out this article for herbs and other natural remedies specific to urinary tract health.
Does Saw Palmetto Really Work?
Like most research, male subjects have been the primary focus making less data available on the application of saw palmetto benefits in women’s health. While data does exist to support the use of saw palmetto in female pattern hair loss, PCOS, and androgen specific conditions, there is certainly room for further investigation.
Clinically, I have seen tremendous benefit utilizing saw palmetto in androgen related hair loss and in supporting women with PCOS. As a naturopathic physician who is board certified in naturopathic endocrinology, I have employed saw palmetto as part of a holistic treatment plan with great success. Many clinicians also report positive patient outcomes with saw palmetto.
It is important to understand that most clinical trials aim to isolate an herb or its constituents to test its benefits on a specific condition. Some clinical trials have been published about saw palmetto and hair loss in men and women, but again, their results need further investigation.
Traditional herbal medicine (remembering that saw palmetto is a traditional Indigenous plant medicine) typically doesn’t treat anything in isolation. Traditional and naturopathic medicine understands that the greatest benefits are achieved through the combination of nutrition, lifestyle, and herbs as a holistic approach to healing.
Therefore, in many high-quality supplements, you’ll find a combination of supporting herbs, vitamins, or minerals that work synergistically.
Saw palmetto is often combined with vitamin B6, diindolylmethane (DIM), zinc, and other nutrients that support testosterone metabolism.
Saw Palmetto Dosage
In general, a daily dose of 320 mg to 450 mg of saw palmetto standardized to 45% fatty acids in capsule form.
Your ideal supplement form and dose will depend on your body’s needs. Working with a licensed health care practitioner can help you dial in your needs.
Supplements may come in either liquid or powdered form.
Powdered saw palmetto generally contains the whole berry dried, crushed, and put into a capsule or tablet.
Extracts, on the other hand, mean the fruit has been through a process to extract the active ingredients. It is usually in liquid form.
Both types of supplements can be beneficial.
What Are the Side Effects of Taking Saw Palmetto?
Saw palmetto is considered safe with the most common issue being digestive upset. Taking saw palmetto with food can prevent any digestive issues from arising. Side effects are not very common and when they do occur, they’re usually mild.
Side effects can include:
When to Avoid Saw Palmetto
While it may be tempting to jump on saw palmetto given its benefits, it’s important to note that it is not for everyone.
If You Are Pregnant and Breastfeeding
Because saw palmetto influences reproductive hormones, including prolactin, it’s best to avoid it in pregnancy and breastfeeding.
If You Are on Hormone-Based Medication
If you are using hormone-based contraceptives or on any hormone replacement therapy, check with your prescribing doctor or pharmacist about potential interactions with saw palmetto. At this time we do not have enough research to understand its impact on these medications.
If you’re using the pill to treat acne, but its persistence has you questioning adding saw palmetto, it may be time to find a new treatment for your acne.
If You Are On Blood Thinners
Saw palmetto may increase your risk of bleeding if you are already on blood thinners like Warfarin.
Remember that high doses of other anti-inflammatory medications such as fish oils and non-steroidal anti-inflammatory medicines can also increase this risk. Be aware of the combination of medicines and supplements you are taking and talk to your health care provider for clarification.
If You Have a Blood-clotting Disorder
If you have a condition that increases your risk of bleeding, always check with your naturopathic doctor if this herb is safe to take. Because of its anti-inflammatory effects, saw palmetto may reduce clotting in the blood.
If You Have Surgery Planned
Saw palmetto should be stopped pre-surgery. The anti-inflammatory effects may increase your risk of bleeding. Therefore, check with your surgeon and naturopathic doctor how far in advance you should stop taking saw palmetto.
Summary of Saw Palmetto Benefits
Overall, saw palmetto is a relatively well-tolerated and safe herb that may help to support healthy testosterone, address prolactin imbalances, and reduce inflammation.
Because saw palmetto may reduce the enzyme responsible for the conversion of testosterone to DHT, you may find an improvement in symptoms associated with high DHT, like hair loss or acne.
If you think saw palmetto could benefit you, you can learn more about our Saw Palmetto Plus here. It is important to work on the root cause of any hormonal imbalances to achieve long-term results.
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