Saw Palmetto: What It Does, How to Use It, and What to Watch For

Thinking about saw palmetto for prostate health or hair loss? You’re not alone. This plant extract, made from Serenoa repens berries, is one of the most used herbal supplements for men’s health. It’s easy to find and marketed for urinary symptoms, benign prostatic hyperplasia (BPH), and sometimes hair thinning.

What it’s used for and what the evidence says

People most often take saw palmetto for urinary symptoms from an enlarged prostate — things like weak urine flow, trouble starting, or waking at night. Clinical studies are mixed. Some smaller trials report modest improvements in symptoms and urine flow. A few high-quality trials showed little or no benefit compared with placebo. Bottom line: it may help some men a little, but it’s not a guaranteed fix.

Some people try saw palmetto for hair loss because of its supposed effect on hormones that affect hair. The evidence there is limited and weaker than for prostate symptoms. If hair regrowth is the goal, standard treatments like minoxidil or finasteride have stronger proof.

Dosage, safety, and interactions

Typical dose is 160 mg twice daily of a standardized extract (total about 320 mg per day). Most studies use a fatty-acid–standardized extract. Follow the label or your health provider’s advice. Don’t assume higher dose equals better results.

Side effects are usually mild: stomach upset, headache, or dizziness. Less common reactions happen, but serious problems are rare. However, saw palmetto can affect blood clotting and might interact with blood thinners like warfarin. It can also have hormonal effects, so avoid if you’re pregnant or breastfeeding — and check with a doctor if you have hormone-sensitive conditions.

Tell your healthcare provider about all your supplements before surgery or if you’re starting blood thinners, hormone therapy, or other prescription meds. If you notice heavy bruising, unusual bleeding, or new symptoms after starting saw palmetto, stop and seek advice.

Quality matters. Look for products that list Serenoa repens, show the amount of extract per serving (for example, 320 mg), and ideally note standardization to fatty acids or sterols. Third-party testing seals (USP, NSF, ConsumerLab) add trust. Avoid multi-ingredient blends if you want to know what’s actually doing the work.

How long to try it? Give a supplement at least 6 to 12 weeks to judge effect for urinary symptoms. If you see no benefit, stop rather than keep paying for something that doesn’t help. If it helps, keep monitoring for side effects and discuss ongoing use with your provider.

Questions about saw palmetto and your situation? Bring them to your doctor or a pharmacist. They can help weigh benefits, risks, and safe alternatives based on your health and current medications.