Serenoa repens herbal extract, dosage, safety, side effects, research studies - Does this herb help with hair growth, or a healthy prostate? by Ray Sahelian, M.D.
September 19 2017

Serenoa repens, the botanical name for saw palmetto, is an herb that has been shown in many, but not all, clinical studies to have beneficial effects in reducing symptoms of benign prostatic hyperplasia (BPH).  Serenoa repens (sometimes referred to as sabal in Europe) grows naturally in the southeast United States, such as Georgia, Mississippi, and particularly Florida.

What's in serenoa repens herb? What are the constituents?
There are a number of compounds within the
berry. As a rule they are divided into four major categories:

1) Free fatty acids. Quite a number of fatty acids are present in
saw palmetto. The ones in highest concentration include oleic acid, lauric acid, myristic acid and palmitic acid.

2) Phytosterols (plant sterols). These plant sterols (phyto means plant) have a chemical structure similar to cholesterol. The most commonly found phytosterols in
Serenoa repens are beta-sitosterol, campesterol, stigmasterol and cycloartenol.
3) Free fatty alcohols. These are usually made up of fatty acids joined to an alcohol molecule.
4) Monoglycerides, which are single fatty acids attached to a three-carbon glycerol molecule.

Prostate Power Rx with Serenoa repens, Pygeum, Stinging Nettle, Quercetin, Lycopene, and several important Ingredients for support of normal prostate size & urine flow

Prostate Power Rx is carefully formulated with high dose serenoa repens and important herbs and nutrients to provide optimal prostate health. Significant clinical research on prostate enlargement has been conducted with the potent herbs in Prostate Power Rx. This prostate formula has been designed to support:



Supplement Facts:
Saw Palmetto extract (standardized to contain 45% fatty acids - serenoa repens fruit)
Stinging Nettle 4:1 extract -(urtica diocia root)
Quercetin  (one study shows the combination of quercetin and finasteride works very well)
Rosemary 4:1 extract (Rosemarinus officinales leaf)
Beta Sitosterol is a phytosterol
Pygeum 4:1 bark extract (Pygeum Africanum)
Genistein (standardized to contain 40% isoflavones)
Daidzein (standardized to contain 40% isoflavones)
(treatment with the isoflavones daidzein and genistein, the estrogen-like compounds found in soy, block prostate growth in rats)
Lycopene (Lycoperscion escatatum fruit)

Is Serenoa repens safe?
No significant side effects have been reported in the medical literature regarding saw palmetto. It does not seem that it influences levels of PSA (prostate-specific antigen) to any significant degree but there is still debate regarding this issue.

For what conditions is eerenoa repens herb useful?
The best known use of serenoa repens herb is for prostate enlargement although research has been inconsistent on its influence on prostate gland tissue.

Cochrane Database Syst Rev. 2012. Serenoa repens for benign prostatic hyperplasia. At double and triple doses, SR did not improve urinary flow measures or prostate size in men with lower urinary tract symptoms consistent with BPH.

Serenoa repens and hair
I am often asked whether serenoa repens extract is useful for hair loss. As of 2016, I have come across few studies in humans evaluating the role of serenoa repens extract, used by itself, in hair loss or restoring hair growth.
One of the causes of hair loss is excess DHT ( a testosterone metabolite) in hair tissue. There is some speculation that saw palmetto is a weak inhibitor of the enzyme (5 alpha reductase) that converts testosterone into DHT in prostate tissue. However, I don't know whether a similar effect would occur in hair tissue on the scalp. For the time being, one should not rely exclusively on serenoa repens for hair growth.

Australas J Dermatol. 2015. Treatment of male androgenetic alopecia with topical products containing Serenoa repens extract. Male androgenetic alopecia (AGA) is a common hair problem. Serenoa repens extract has been shown to inhibit both types of 5-α reductase and, when taken orally, has been shown to increase hair growth in AGA patients. The aim of this study was to assess the efficacy of topical products containing S. repens extract for the treatment of male AGA. This was a pilot, prospective, open, within-subject comparison limited to 24 weeks using no placebo controls. In all, 50 male volunteers aged between 20 and 50 years received topical S. repens products for 24 weeks. The primary end-point was a hair count in an area of 2.54 cm2 at week 24. Secondary end-points included hair restoration, investigators' photographic assessment, patients' evaluation and discovering adverse events. The average hair count and terminal hair count increased at weeks 12 and 24 compared to baseline. Some of these positive results levelled off at week 24, presumably because the concentrated topical product containing S. repens extract was stopped after 4 weeks. The patients were satisfied with the products and the side-effects were limited. The topical application of S. repens extract could be an alternative treatment in male pattern baldness in male patients who do not want or cannot tolerate the side-effects of standard medications, but the use of a concentrated S. repens product beyond 4 weeks may be necessary for sustained efficacy.

Comparison of the potency of different brands of Serenoa repens extract on 5alpha-reductase types I and II in prostatic co-cultured epithelial and fibroblast cells.
Pharmacology. 2008: Scaglione F, Lucini V, Pannacci M, Caronno A, Leone C. Department of Pharmacology, School of Medicine, University of Milan, Milan, Italy.
Serenoa repens extract is the phytotherapeutic agent most frequently used for the treatment of the urological symptoms caused by benign prostatic hyperplasia. There are many extracts in the market and each manufacturer uses different extraction processes; for this reason, it's possible that one product is not equivalent to another. The aim of this study was to compare the activity of different extracts of Serenoa repens marketed in Italy. The following extracts were tested on 10 day co-cultured epithelial and fibroblast cells by a 5alpha-reductase activity assay: Permixon, Saba, Serpens, Idiprost, Prostamev, Profluss and Prostil. In order to assess the variability in Serenoa repens products, 2 different batches for each brand were evaluated. All extracts tested, albeit variably, are able to inhibit both isoforms of 5alpha-reductase. However, the potency of the extracts appears to be very different, as well as the potencies of 2 different batches of the same extract. This is probably due to qualitative and quantitative differences in the active ingredients. So, the product of each company must be tested to evaluate the clinical efficacy and bioactivity.

Serenoa repens and prostatitis
Results of a multicenter trial of serenoa repens extract (permixon) in patients with chronic abacterial prostatitis
Urologiia. 2007. Lopatkin NA, Apolikhin OI, Sivkov AV, Aliaev IuG, Komiakov BK, Zhuravlev VN, Oshchepkov VN, Vinarov AZ, Bazhenov IV, Medvedev AA, Spivak LG, Eliseenko AG.
A multicenter trial conducted by the authors demonstrates high efficacy of Permixon in the treatment of chronic prostatitis / chronic pelvic pain syndrome. The results of 6-month follow-up are presented.

How does Serenoa repens extract work?
Unfortunately, many herbal and natural medicines have had far less research money devoted to them than they deserve. Serenoa repens extract is no exception. Consequently, we don't know all the answers to the exact mechanisms of how the different compounds within serenoa repens work. However, there have been enough studies to give us some clues. Some of most likely mechanisms include the reduction in the amount of dihydrotestosterone (DHT) in prostate tissue, inhibition of binding of DHT to androgen receptors in prostate cells, and the anti-estrogenic action in prostate tissue. Another possibility is the ability of compounds within Serenoa repens to reduce the action of IGF-1 on prostate tissue.
Insulin-like growth factor (IGF) action is important for prostate growth and development, and changes in the IGF system have been documented in BPH tissues.

   Unlike Proscar (finasteride), which has one active ingredient, Serenoa repens has a number of different compounds within it. Thus, you can see why it would be complicated to evaluate all the possible interactions that these compounds have on a variety of tissues within our bodies. Furthermore, it is possible that a single compound within Serenoa repens may not have much of an influence on its own although its combination with the other compounds would have a synergistic effect.
   The more I learn about the human body, the more I realize how complicated it is. Early in my medical career I unquestioningly accepted the results of studies done in a laboratory or on animals and was quick to use this information to generalize to humans. I now know otherwise. In order to understand truly how a medicine works, it has to be studied directly on humans. Although laboratory and animal studies can give us important information, they are never a replacement for thorough human evaluations.            
   Another complicating factor is that modern medicine does not advance solely on the basis of seeking the most efficient therapy for human diseases. There are significant economic factors that influence the funding of studies, the subsequent interpretation of the results, and especially the dissemination of this information. Many of the studies done with Serenoa repens were financed either by companies who market this extract, such as Pierre Fabre Medicament, or by pharmaceutical companies, such as Merck, who have developed competing drugs that treat prostate enlargement. Merck has the drug Proscar. Not surprisingly, the results of studies obtained by Merck scientists on Serenoa repens are often in disagreement with the results obtained by scientists working under the auspices of saw palmetto-selling companies.

Side effects, safety, caution, risk
Pharmacology. 2015. Serenoa repens as an Endocrine Disruptor in a 10-Year-Old Young Girl: A New Case Report. Its fruits contain high concentrations of fatty acids and phytosterols. S. repens extracts have been studied for the symptomatic treatment of benign prostatic hyperplasia. Recently, they have been proposed to treat androgenic alopecia and other hair disorders. We report a new case of hot flashes in a 10-year-old girl using a food supplement containing the extract of S. repens for the treatment of hirsutism. When the girl discontinued the treatment, the hot flashes stopped. A 'rechallenge' of the supplement was tried and symptoms reappeared. About 4 months after starting therapy, the girl experienced menarche. Exposure to the plant-derived product could be responsible for the appearance of menarche.

Serenoa Repens: Berry or extract?
When you purchase
saw palmetto, you will find some bottles that provide crushed berries, not the extracts. Until we learn more about the effects of using the full contents of the berries, I recommend that you buy the extracts. The extracts will contain the actual substances that are effective in treating BPH in a much higher concentration. The berries will provide you with smaller amounts of the needed active ingredients. Whether the crushed berries have compounds that provide other benefits is not fully known at this time. If you want to take Serenoa repens berries, you may need to ingest at least one or two grams a day. The ratio of the dried berry to the lipophilic extracts is usually about 10 to 1. Some users prefer to take both the extracts and the berries, thinking that there are substances within the full berries that could be beneficial. We certainly need more research in order to have a fuller understanding.

Does Serenoa repens interfere with medications?
Limited research suggests that Serenoa repens does not influence the ability of the liver to metabolize other drugs, for instance Serenoa repens does not alter the activity of
cytochrome P450.

What about combining Serenoa repens with other herbs?
Research shows when taken for 3 months, a combination of natural products (rye pollen extract, saw palmetto, Beta sitosterol, and vitamin E) compared to placebo can significantly lessen nocturia and frequency and diminish overall symptoms of prostate enlargement. (See below for the full study.)

Ask your urologist about Serenoa repens before he reaches for the surgical equipment
Serenoa repens may also be helpful before a surgical procedure called transurethral resection of the prostate. Pretreatment with serenoa repens, before a TURP procedure, improves the efficacy of the procedure itself and reduces the risk of complications, in particular perioperative bleeding and duration of postoperative catheterization.

Serenoa Repens Research studies
Serenoa repens treatment modifies bax/bcl-2 index expression and caspase-3 activity in prostatic tissue from patients with benign prostatic hyperplasia.
 J Urol. 2005.
Permixon is a lipidosterolic extract of Serenoa repens extract widely used to treat men with benign prostatic hyperplasia (BPH). We tested the effect of this Serenoa repens extract on molecular mechanisms associated with apoptosis, such as the Bax-to-Bcl-2 expression ratio and caspase-3 activity, in prostatic tissue from men with symptomatic BPH treated for 3 months before surgery.  Serenoa repens extract increased molecular markers involved in the apoptotic process, ie the Bax-to-Bcl-2 expression ratio and caspase-3 activity. This could have clinical relevance due to the improvement in symptoms produced by treatment with Serenoa repens extract.

Preventing diseases of the prostate in the elderly using hormones and nutriceuticals.
Aging Male. 2004.
The prostate has only one function, namely to secrete fluid containing substances that are needed for reproduction. This requires an extremely high concentration of androgens in the tissues. Benign prostatic hypertrophy (BPH) seems to be related to the long-term exposure of the prostate to the strong androgen 5alpha-dihydrotestosterone (DHT) and, possibly, to estrogens. The relation between prostate cancer and androgens is suggested to be U-shaped, with both extremes of androgen concentrations being associated with increased risk of invasive cancer. In the treatment of patients with BPH, the lipidic liposterolic extracts of Serenoa repens were as effective as the pharmaceutical inhibitors of the 5alpha-reductase enzyme or alpha1-adrenergic blockers in relieving urinary symptoms. In addition to moderately inhibiting the 5alpha-reductase activity, Serenoa seems to exert anti-inflammatory and complementary cellular actions with beneficial effects on the prostate. Unlike the pharmaceutical 5alpha-reductase inhibitors, finasteride and dutasteride, Serenoa does not suppress serum PSA, facilitating the follow-up and the early detection of prostate cancer. We suggest a strategy to prevent prostate cancer that aims at providing men with partial androgen deficiency correct testosterone substitution with a sustained release buccal bio-adhesive tablet. In addition, food supplementation with extracts of Serenoa repens and a combination of the antioxidants selenium, lycopene and natural vitamin E, together with fish oil rich in long-chain polyunsaturated essential fatty acids of the omega-3 group seems warranted. Clearly, a holistic approach including careful clinical and biological monitoring of the aging man and his prostate remains mandatory.

The role of a lipido-sterolic extract of Serenoa repens in the management of lower urinary tract symptoms associated with benign prostatic hyperplasia.
BJU Int. 2004.
To examine the clinical profile of medication derived from a lipido-sterolic extract of Serenoa repens (saw palmetto) for managing lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia (BPH). We reviewed clinical trials involving extracts of Serenoa repens, focusing on the benefit/risk ratio in patients with BPH. . repens extract significantly reduces the symptoms of BPH, increases urinary flow, improves the quality of life and is well tolerated. Analysis of the overall clinical database indicates that extract of Serenoa repens may be considered a viable first-line therapy for treating LUTS.

Serenoa repens ( Permixon(R) - saw palmetto ) inhibits the 5alpha-reductase activity of human prostate cancer cell lines without interfering with PSA expression.
Int J Cancer. 2004;
The phytotherapeutic agent Serenoa repens is an effective dual inhibitor of 5alpha-reductase isoenzyme activity in the prostate. Unlike other 5alpha-reductase inhibitors, Serenoa repens induces its effects without interfering with the cellular capacity to secrete PSA. Here, we focussed on the possible pathways that might differentiate the action of Permixon from that of synthetic 5alpha-reductase inhibitors. We demonstrate that Serenoa repens, unlike other 5alpha-reductase inhibitors, does not inhibit binding between activated AR and the steroid receptor-binding consensus in the promoter region of the PSA gene. This was shown by a combination of techniques: assessment of the effect of Permixon on androgen action in the LNCaP prostate cancer cell line revealed no suppression of AR and maintenance of PSA protein expression at control levels. This was consistent with reporter gene experiments showing that Permixon failed to interfere with AR-mediated transcriptional activation of PSA and that both testosterone and DHT were equally effective at maintaining this activity. Our results demonstrate that despite Serenoa repens effective inhibition of 5alpha-reductase activity in the prostate, it did not suppress PSA secretion. Therefore, we confirm the therapeutic advantage of Serenoa repens over other 5alpha-reductase inhibitors as treatment with the phytotherapeutic agent will permit the continuous use of PSA measurements as a useful biomarker for prostate cancer screening and for evaluating tumour progression.

Effect of permixon (Serenoa repens extract) on human prostate cell growth: Lack of apoptotic action.
Hill B, Kyprianou N. Division of Urology, University of Maryland School of Medicine, Baltimore, Maryland.
Prostate. 2004.
Permixon, a phytotherapeutic agent derived from the Serenoa repens plant, is a lipid/sterol extract that is believed to interfere with 5alpha-reductase activity, thus inhibiting prostate growth. In this study, we investigated the magnitude and specificity of the effect of Serenoa repens extract on cell proliferation and apoptosis in human prostate cancer cells. The effect of Serenoa repens extract was examined in androgen-independent PC-3 prostate cancer cells, androgen-sensitive LNCaP prostate cancer cells, and MCF-7 breast cancer cells in vitro. Cell growth, apoptosis induction, and cell proliferation was studied after exposure to Serenoa repens extract at two concentrations (10 and 100 microg/ml). Cell proliferation and cell cycle progression were determined after 24 hr on the basis of (3)[H]-thymidine incorporation assay and flowcytometric analysis, respectively. Apoptosis induction was evaluated in treated and untreated cultures using the Hoescht staining and caspase-3 activation. Exposure of prostate and breast cancer cells to a high dose of Serenoa repens extract (100 microg/ml) resulted in a significant decrease in the rate of cell growth; an effect that was not time-dependent and was not associated with cell cycle arrest. Serenoa repens extract treatment (at either high or low dose) had no effect on apoptosis induction in prostate cancer cell lines. Furthermore, in vitro it was a weak inhibitor of 5alpha-reductase activity type 2 in prostatic homogenates. The results indicate the ability of Serenoa repens extract to affect prostate cancer cell growth without inducing apoptosis or cell cycle arrest. This effect was not prostate-specific and was only manifested at high concentrations of Serenoa repens extract. Furthermore our findings indicate that Serenoa repens extract is weak inhibitor of 5alpha-reductase compared to finasteride. This study challenges previous evidence on the anti-growth effect of Serenoa repense xtract in the prostate and its ability to inhibit 5alpha-reductase activity, while questioning apoptosis as a mechanism of action of this phytotherapeutic against prostate growth, a concept that may have therapeutic significance.

Efficacy of pretreatment with Serenoa repens on bleeding associated with transurethral resection of prostate]
Minerva Urol Nefrol. 2004.
AIM: Aim of the study is to evaluate the efficacy of a pretreatment with lipidic-sterolic extract of Serenoa repens( Permixon ) to reduce bleeding during transurethral resection of prostate (TURP) in patients with benign prostatic hyperplasia. This is a monocentric, randomised versus control group study. We enrolled 108 patients, randomised either in the Serenoa repens group or in the control one. Patients in the Serenoa repensgroup received a pretreatment with Serenoa repens (320 mg/die of Permixon ) for at least 8 weeks before the TURP procedure. In the control group patients did not receive any medical treatment before the intervention. Out of 108 enrolled patients, 88 were evaluated per protocol. In the Serenoa repens group the perioperative bleeding was significantly lower than in the control one (respectively 124 vs 287 ml) and the need of transfusion decreased remarkably. Moreover, in the Serenoa repens group, the duration of postoperative catheterization (respectively 3 vs 5 days) and the evaluated hematological parameters (red cells 4.5 vs 4 million, hemoglobin 13 vs 11.9 g, hematocrit 40% vs 35%) were significantly lower than in the control group. The pretreatment with saw palmetto, before TURP procedure, improves the efficacy of the procedure itself and reduces the risk of complications, in particular perioperative bleeding and duration of postoperative catheterization.

Updated meta-analysis of clinical trials of Serenoa repens (saw palmetto) extract in the treatment of symptomatic benign prostatic hyperplasia.
BJU Int. 2004.
To determine, by analysing all available clinical trial data, the clinical efficacy against placebo of an extract from the fruit of the American dwarf palm tree, Serenoa repens (Permixon, Pierre Fabre Medicament, Castres, France), as there is controversy about the use of phytotherapeutic agents in men with lower urinary tract symptoms suggestive of benign prostatic hyperplasia (BPH). All clinical trial data published on Permixon (saw palmetto), comprising 14 randomized clinical trials and three open-label trials, involving 4280 patients, were analysed. These trials were of different size (22-1100 patients) and duration (21-720 days). The peak urinary flow rate and nocturia were the two common endpoints. The statistical analysis was based on a random-effects meta-analysis. Serenoa repens was associated with a mean reduction in the International Prostate Symptom Score of 4.78. The mean placebo effect on peak urinary flow rate was an increase of 1.20 mL/s. The estimated effect of Serenoa repens was a further increase of 1.02 (0.50) mL/s. Placebo was associated with a reduction in the mean number of nocturnal voids of 0.63; there was a further reduction attributable to Serenoa repens of 0.38. There was some heterogeneity among the studies for nocturia; one over 2 years involving 396 patients and showing no difference between placebo and Permixon had a large effect on the results. This meta-analysis of all available published trials of Serenoa repens for treating men with BPH showed a significant improvement in peak flow rate and reduction in nocturia above placebo.

Comparison of Serenoa repens (extract and whole berry) and Cernitin on prostate growth in rats.
Mol Cell Biochem. 2003.
Pharmaceuticals such as finasteride and alpha blockers are used to treat symptoms of benign prostatic hyperplasia (BPH) and are known to cause severe adverse reactions. Accordingly, a search for safer, natural products has been undertaken. Two natural agents (nutraceuticals) have come under recent scrutiny; because natural products, in general, often have evidence of long-term safety. The present study compares the in vivo effects on androgen-induced prostatic enlargement in rats of two nutraceuticals--the widely recognized Serenoa repens and the less well-known Cernitin (defined rye pollen extract). Non-castrated rats, had a mean prostate weight of 124 mg (S.E.M.) compared to the 24 mg (S.E.M.) of the castrated rat followed under the same regimen. When castrated rats were given testosterone, the mass increased significantly to 250.0 mg (S.E.M.). In the five remaining groups, castrated rats receiving testosterone were given finasteride, an extract of Saw Palmetto, crushed whole berry derived from Serenoa repens fruit, a water soluble and fat soluble extract of Cernitin or a combination of the Serenoa repens extract and Cernitin. All treatments decreased the size of the prostate to roughly the same size as in the non-castrated rats, a size that was significantly smaller than castrated rats treated with testosterone in the same manner. A second study examining non-castrated rats treated with very high doses of testosterone showed similar results. In both studies, the nutraceuticals generally decreased body weight. In conclusion, these studies show the ability of Serenoa repens (whole berry and extract) and Cernitin to influence prostatic hyperplasia via effects on androgen metabolism.

Long-term clinical and biologic effects of the lipidosterolic extract of Serenoa repens in patients with symptomatic benign prostatic hyperplasia.
Adv Ther. 2002.
Permixon, the lipidosterolic extract of Serenoa repens (saw palmetto), is widely used for the treatment of symptoms associated with benign prostatic hyperplasia (BPH). This open study assessed the efficacy and tolerability of saw palmetto160 mg twice daily administered for 2 years. One hundred fifty-five men with clinically diagnosed BPH and complaints of prostatic symptoms were enrolled in the study. At 6, 12, 18, and 24 months, the International Prostate Symptom Score (I-PSS), quality of life, and sexual function score were recorded, and urodynamics and biologic values were measured. Adverse events were recorded every 3 months. I-PSS and quality of life for those on Serenoa repens improved significantly from baseline at each evaluation time point. At the end of the study and at each evaluation, maximum urinary flow also improved significantly. Prostate size decreased. Sexual function remained stable during the first year of Serenoa repens treatment and significantly improved during the second year. Prostate-specific antigen was not affected, and no changes in plasma hormone levels were observed. Nine patients reported 10 adverse events, none related to treatment with saw palmetto. Improvements in efficacy parameters began at 6 months and were maintained up to 24 months. These data demonstrate the long-term efficacy and tolerability of Serenoa repens and support its use as a first-line medical therapy for uncomplicated symptomatic BPH.

The lipidosterolic extract of Serenoa repens in the treatment of benign prostatic hyperplasia: a comparison of two dosage regimens.
Adv Ther. 2002.
This 6-month double-blind, randomized, parallel-group study compared two dose regimens of Libeprosta, the lipidosterolic extract of Serenoa repens (saw palmetto) in 100 male outpatients with lower urinary tract symptoms suggestive of benign prostatic hyperplasia (BPH). The patients received two 80-mg tablets twice daily or two 80-mg tablets three times daily. Baseline evaluations included maximum and mean urinary flow rates, postvoid residual urine volume, and International Prostate Symptom Score (I-PSS) total and quality-of-life scores. Both regimens significantly reduced the I-PSS mean total score from baseline values; improvements achieved statistical significance after month 3 and were maintained for the duration of the study. Significant improvements from baseline also occurred in quality-of-life scores, maximum and mean urinary flow rates, and residual urine volume. The decrease in residual urine with both regimens was highly significant. No significant differences in efficacy were noted between the two dose groups, and no treatment-related complications or clinical adverse events occurred. In this clinical study, the lipidosterolic extract of Serenoa repens was a well-tolerated agent that may significantly improve lower urinary tract symptoms and flow measurements in men with BPH.

Serenoa repens May Help Battle Prostate Cancer
Extract from the Serenoa repens berry, a commonly used herbal supplement taken by men with enlarged prostates, may also have anti-cancer properties, researchers announced at a meeting of The American Society for Cell Biology. "Since we knew that Serenoa repensberry extract had some effect on the prostate, we decided to take this a step further. We wanted to know if the Serenoa repens had any effect on prostate cancer cells," said researchers at Children's Hospital in Boston, Massachusetts. The research team analyzed the effects of Serenoa repens berry extract on cancer cells. To accomplish this, they exposed prostate cancer cells and a generic cancer cell line to various concentrations of berry extract. The cancer cell growth in laboratory cell cultures was then monitored. About one-fifth the amount of berry extract was needed to decrease the cell growth of the prostate cancer cells compared to the amount needed to slow down the growth of the generic cancer cells.
Dr. Sahelian says: Men who take it for enlarged prostates now can benefit even more by having a possibly lower risk in developing prostate cancer.

Serenoa repens herbal extract emails
Hello doctor, I had taken Serenoa repenst o try to inhibit hair loss about 5 months ago. Most studies show that it is useful in treating BPH but also inhibits DHT in the prostate.  Have you had any experience with anyone that experienced serious side effects using this? I am currently suffering serious erectile dysfunction issues. And from your website i read that Serenoa repens reduces IGF action and DHT in the prostate. My question is that is this permanent? Will the prostate continue to grow once this IGF is reduced and DHT upon stoppage of this drug?
   A. First, it is difficult to say what kind of effect Serenoa repens has on hair follicles and hair growth. My suspicion is that it has little influence (as opposed to finasteride, Proscar, Propecia) although we just don't know for certain since the role of Serenoa repens and hair growth has not been studied to any great extent. Thus far I have not come across any serious side effects from the use of saw palmetto. I suspect any influence that Serenoa repenshas over prostate tissue is reversible once the Serenoa repens is stopped.

Q. I read you article on Serenoa repens ( saw palmetto ) and hair loss.... What is your opinion ( I know research is lacking ) on combining Finasteride with Serenoa repens ( saw palmetto ) ---given the former is a type 2 inhibitor whereas the Serenoa repens ( saw palmetto ) is a dual inhibitor would you speculate there may be a beneficial effect on hair loss or an adverse one involving hormonal feedback loops ?
   A. You ask a good question. i don't see any obvious harm adding serenoa repens to finasteride, but I honestly don't know whether there would be a synergistic effect. I still am not convinced daily use of finasteride for hair loss or prostate enlargement is safe in the long run. Finasteride may blunt sexuality, but more research is needed.

Q. Is there info available re taking Serenoa repens along with prescription meds such as high blood pressure meds?
   A. As far as we know, Serenoa repens does not interfere to any clinical degree with other medicines.

Q. Have you, by perusing research, or through clinical experience found anything to suggest that Serenoa repens may reduce erectile efficiency ?
   A. I have not come across any research nor have noticed any significant influence of Serenoa repens on erectile dysfunction.

Q. Does Serenoa repens really enhance the glands in the breast tissue?
   A. I haven't seen little research regarding the effect on breast tissue, except one test tube study that showed it may slow the growth of breast cancer cells.

Q. I have read somewhere that Serenoa repens might be used to treat adult acne. I have the type that form in cysts...they're painful, and I'm 24. What do you know about this?
   A. It is unlikely that Serenoa repens helps acne. You may try eating more cold water fish such as halibut and salmon, and more vegetables, while cutting back on nuts and refined carbohydrates. Omega-3 oils in fish are likely to benefit your skin.

Q. I'm a 52 yrs old very healthy male. I  wake up at nite about 3-4 times, my PSA level has not changed since last year which is 5.1 , then i was examined by my urologist, no lump was found during my rectal examination, he prescribed a drug. I read your article and i want to take this Serenoa repens you described. My question is will this saw  interfere with my medication or i can take it any time?, will this extract will help to reduce my PSA level ? will this extract work in very short time and stop or i have to take it for life?
   A. Serenoa repens should not interfere with drugs used for prostate enlargement. I doubt if it will reduce PSA levels. Serenoa repens should be taken for many years as long as there is prostate enlargement.

Q. I read frequently that supplements that increase testosterone can result in unwanted prostate growth. If male testosterone levels naturally decline with age, why does supplementing to bring these levels up to their former values cause ill effects? Why don't 18 year old males have giant prostates?(!)
   A. Good question. It's difficult to know exactly what's going on in prostate tissue and how testosterone, in different age groups, has an effect. But, it may be that the biochemical system within prostate tissue is quite able to handle high androgen levels in the youth but is not able to handle these high androgen levels too well as the person gets older thus leading to prostate enlargement.

Q. I take Propecia to combat male pattern hair loss and was wondering whether it would be just as effective to take Serenoa repens instead. I recall that at the time your book was written, it was inconclusive as to whether Serenoa repens could prevent or reverse such hair loss. Are any such studies in the works? And, would supplementation with standardized serenoa repens extract be as effective as Propecia?
   A. It is unlikely that serenoa repens would work as well, if at all, for hair growth. Serenoa repens appears to be a very weak 5-alpha-reductase inhibitor.

The Science of Saw Palmetto
(excerpt from Dr. Sahelian's book on saw palmetto)

The Proof is In the Flow
One of the earliest studies evaluating the role of Serenoa repens in the therapy of BPH was done in 1984 by Dr. Champault and colleagues at the Hospital Jean Verdier in Bondy, France. These researchers used a trademarked version of Serenoa repens extract named Permixon, which is owned by a French company called Pierre Fabré Medicaments. (Other trademarks include Capistan, Strogen, Libeprosta and Sereprostat.) Permixon's main components are free (90%) and esterified (7%) fatty acids, sterols, flavonoids and other substances (Carraro, 1996).

Fifty-five patients with BPH who had symptoms of frequent urination, nocturia, and poor urinary flow were given 160 mg of Serenoa repens twice a day for 30 days. The results were compared to another group that received placebo pills. At the end of this period, both objective measurements of urinary flow and subjective reporting from patients had improved on average by 50 percent compared to placebo. Serenoa repens was well tolerated with only minor side effects reported, one being headaches. Standard blood chemistry measurements showed no changes. The researchers conclude, "As predicted from pharmacological and biochemical studies, Serenoa repens appears to be a useful therapeutic tool in the treatment of benign prostatic hyperplasia." (A note worth mentioning at this point is that many of the studies evaluating the effects of Serenoa repens were conducted or funded by the pharmaceutical company that sells Permixon, the trademarked version of Serenoa repens extract.)

Champault and colleagues published a follow up study that involved administering Serenoa repens to 47 patients with prostatic adenoma. An adenoma is a benign growth or cancer that has a very low risk of spreading or expanding. The study period this time went for 14 months, and in some cases up to two and a half years. They found Serenoa repens to be efficacious and perfectly tolerated (Champault, Bonnard, 1984).

Two years later, a British group headed by Dr. Reece Smith, from the Department of Urology and Radiology at Southampton General Hospital, repeated a similar study. Thirty-three patients were given Serenoa repens at 160 mg twice daily and compared to a group of 37 individuals who did not receive any therapy. Interestingly, both the medication treated group and the placebo group had a significant improvement in flow rate and symptoms. No side effects were noted on Serenoa repens except for two patients who had nausea, and one who reported an increase in sexual drive. The researchers did not seem to be completely convinced of saw palmetto's benefits. They say, "In conclusion, whilst the regime of Serenoa repens used in this trial was safe, well tolerated and associated with considerable, symptomatic improvement, we have no evidence that this improvement was due to anything more than the psychosocial value of being involved in the trial and meeting a number of sufferers from a similar condition."

With these conflicting reports on the effectiveness of saw palmetto, an extensive study was sorely needed. Fortunately, such as study was published in 1996. Not only did it evaluate the effectiveness of Serenoa repens in the therapy of BPH, but it also compared Serenoa repens to Proscar, the medical gold standard in the therapy of BPH.

The Longest Serenoa repens atudy
Although doctors have used it with patients for over a decade, an actual study evaluating the long-term use of this herb was not published until 1996 (Bach). This was a trial conducted in Germany, where doctors have been using Serenoa repens and other herbs for the therapy of BPH on a regular basis for many years. A total of 89 urologists and 435 patients entered the 3-year prospective study and 315 patients completed it. The patients' age ranged between 41 and 89 years. They were treated with Serenoa repens at 160 mg twice a day for 3 years.

The results showed nocturia to be improved in 73 percent of the patients. At the start of the study, only 13 patients did not have nocturia, whereas, at the conclusion of the 3-year trial, 114 patients were symptom-free. Daytime frequency improved in 54 percent of the patients. Residual volume diminished by 50 percent. With respect to digital rectal examination, after three years of therapy with saw palmetto, no changes in the size of the prostate could be determined.

Overall, 80 percent of the patients and doctors felt the improvements on Serenoa repens were either good or very good. The researchers conclude, "If one compares the results of the present three-year study of IDS 89 (Serenoa repens extract) with published data on the long-term treatment of BPH using synthetic active ingredients--i.e. a three-year finasteride study (Stone, 1994), and an 18-months study on the selective alpha-1-blocker, terazosin (Wilde, 1993)--one can, despite methodological reservations, conclude somewhat unexpectedly that better clinical efficacy [effectiveness] has been documented in respect to the Serenoa repens preparation. Withdrawal from therapy because of adverse events was 1.8 percent with Serenoa repens, as opposed to 11 percent with finasteride and 10 percent with terazosin."

This study is very important because it has been known that patients with BPH have a significant response to placebo that can go on for many months, and even up to two years. This finding was reported by Dr. J. Curtis Nickel, professor or urology at Queen's University Faculty of Medicine in Kingston, Ontario, at the 1997 annual meeting of the American Urological Association (Family Practice News, August 1, 1997, p30). Therefore, the 3-year study reported above lends additional credence to the effectiveness of saw palmetto. Unfortunately, this 3-year study was not placebo-controlled. Hence, more long-term, placebo-controlled studies are required to satisfy the skepticism of critics.

The Hungarian
A Hungarian Serenoa repens study published in 1997 is another one to show the effectiveness of Serenoa repens (Kondas, 1997). Thirty-eight patients with symptoms of BPH were given Serenoa repens for a 12-month period. Nearly three fourths of the patients reported improvements, and no side effects were observed. According to studies measuring the urine flow, the peak flow rate (how fast the urine comes out of the bladder) increased significantly and the amount of urine left in the bladder decreased or was nil in nine out of the ten patients. The size of the prostate gland decreased by 10 percent. The researchers say, "On the basis of this favorable experience, the authors recommend the administration of Serenoa repens extract in the treatment of patients with mild or moderate symptoms of prostatic hyperplasia."

The results of numerous studies published over the past 20 or so years indicate that Serenoa repens improves symptoms in a reasonable number of patients suffering from BPH. The benefits often occur without a dramatic decrease in the size of the prostate gland. The response to Serenoa repens is similar in many ways to that of finasteride, even though they probably work in different ways.