Polypodium Leucotomos
Polypodium leucotomos, also classified as Phlebodium aureum and known as golden polypody, is a fern native to Central and South America, where its rhizomes and fronds have a history of traditional use. This product contains the whole herb, milled to a powder.
How skin responds to ultraviolet light, using an extract of the same fern: placebo-controlled trials, a safety study, a 2025 systematic review and a drug-interaction study. See the studies
On the label
Hypromellose (vegetarian capsule), rice flour, organic rice concentrate (NuFlow).
As a dietary supplement, take two capsules with food whenever preferred. Do not consume more than two capsules per day.
The other two ingredients
Apart from the polypodium powder, the capsule holds two things: rice flour and a cellulose shell. Both are food.
The shell is hypromellose, which is plant cellulose refined into a clear film. It keeps the powder dry until you swallow it, then dissolves in the stomach in a few minutes. No gelatin, so nothing from an animal, and no colouring.
Two hundred and fifty milligrams of polypodium powder is a small pinch. On its own it would sit loose in a half-empty shell, and a half-empty capsule cannot be filled to a consistent weight. Rice flour makes up the difference. Each capsule is filled to the same weight, and that weight is how the dose is checked.
This powder is sticky, so a little organic rice concentrate (NuFlow) goes in to keep it flowing evenly on the filling machine. It is finely ground rice hull and nothing more. It does the job most brands give to silicon dioxide.
That is the full list. Nothing else goes in.
What the bottle does
The bottle is amber PET. It is what the pharmaceutical industry uses for tablets and capsules because, of the common bottle plastics, it lets the least oxygen through. It has no BPA and no phthalates in it. It does not break like glass and weighs much less, so shipping it takes less fuel. It is also the most recycled plastic there is, the number one inside the triangle on the base.
Light, air and moisture are what age a capsule. The amber tint blocks the ultraviolet. A tear-resistant seal under the cap keeps air and moisture out until you break it.
A band around the neck shows the bottle has not been opened since it was filled. A cotton insert stops the capsules rattling and breaking in the post. The lot number and date on the base link the bottle to its certificate.
Keep it somewhere cool, dry and dark.
Questions about Polypodium Leucotomos
Is this an extract?
No. It is the whole herb, dried, milled to a powder and encapsulated, 250 mg per capsule and 500 mg per two-capsule serving. No solvents, no processing beyond drying and milling, so the capsule holds the plant as harvested.
Which plant is it?
Polypodium leucotomos, also classified as Phlebodium aureum and known as golden polypody, a fern native to Central and South America.
How do I get the certificate for my lot?
Email the lot number printed on the base of your bottle to support@symnutrition.com and we will send the certificate of analysis for that lot within two business days.
The studies
These are some of the studies that convinced us this was a product worth making. There is an inherent bias in the interaction between a brand and its customer, so we do not summarise them for you. Each is listed as published with its design, size and dose, including the ones with mixed or null results, and the link goes to the paper. Read them, and do your own research using unbiased and reputable sources.
-
Oral Polypodium leucotomos extract decreases ultraviolet-induced damage of human skin
Middelkamp-Hup MA et al. (2004). Journal of the American Academy of Dermatology. Controlled experimental study, n = 9, 7.5 mg/kg orally.
-
Safety and Efficacy of Oral Polypodium leucotomos Extract in Healthy Adult Subjects
Nestor MS et al. (2015). Journal of Clinical and Aesthetic Dermatology. Randomised, double-blind, placebo-controlled, safety, n = 40, 240 mg twice daily for 60 days.
-
Ahmed AM et al. (2013). JAMA Dermatology. Randomised, double-blind, placebo-controlled, 240 mg three times daily for 12 weeks.
-
Goh CL et al. (2018). Journal of Clinical and Aesthetic Dermatology. Randomised, double-blind, placebo-controlled pilot, n = 40, 480 mg twice daily for 12 weeks, with hydroquinone and sunscreen.
-
The Utility of Oral Polypodium Leucotomos Extract for Dermatologic Diseases: A Systematic Review
Zundell MP et al. (2025). Journal of Drugs in Dermatology. Systematic review of 21 articles including 11 RCTs, 120 to 1080 mg/day.
-
Shinya K et al. (2023). International Journal of Dermatology. Open-label drug-interaction study, n = 6, 240 mg three times over two days.
Polypodium Leucotomos 500mg per serving of 2 capsules, 180 vegetable capsules
Six-month refund. If anything is not right, email your Amazon order ID and we will sort it out. No questions.