The Health Benefits of Polypodium Leucotomos

Polypodium leucotomos is a fern that grows wild in the rainforest and has been used as a folk remedy in Central America for centuries. A tincture made from the plant's rhizomes (underground stems) may help to prevent sunburn, relieve psoriasis, and treat the skin condition vitiligo.

In Western medicine, commercial extracts of Polypodium leucotomos have been available since the 1970s. It is the primary ingredient in oral sun blockers, such as Heliocare, Solaricare, Fernblock, and Shield d'Soliel. Also known as golden serpent fern or cabbage palm fern, the plant's protective properties are believed to be due to its rich stores of antioxidants.

Research on the health benefits of Polypodium leucotomos is limited to animal and test-tube studies, and small clinical trials. However, there is evidence to suggest it may have antioxidant and anti-inflammatory properties that are helpful for treating certain skin conditions. Here's a closer look at the research:

Preliminary studies suggest that Polypodium leucotomos may help to prevent sunburn or reduce its severity. A small study published in the Journal of the American Academy of Dermatology in 2017 found an oral formulation of Polypodium leucotomos reduced skin damage from ultra-violet B (UVB) rays.

A 2016 literature review of Fernblock, a supplement containing Polypodium leucotomos, found it may prevent sun damage from both UVA and UVB rays, and may even help to prevent skin cancer.

Larger trials are still needed to determine its effectiveness against sunburn and other sun damage to the skin.

In alternative medicine, polypodium extracts have been used to treat psoriasis in Europe and Central and South America. Large, well-designed studies, however, are needed before it can be recommended as a treatment for psoriasis.

A 2004 study published in the Journal of the American Academy of Dermatology examined whether Polypodium leucotomos could reduce the side effects of PUVA treatment. PUVA is used in patients with moderate-to-severe psoriasis and consists of psoralen (a light-sensitizing medication) plus ultraviolet light A. For people with lighter skin, the use of PUVA is currently limited by risks of skin damage and skin cancer.

The small pilot study looked at PUVA alone compared with PUVA plus Polypodium leucotomos taken orally. Skin cells of the study participants were examined under a microscope and those taking polypodium were found to have less skin damage compared with those taking the placebo.

While the research is promising, more studies are needed before Polypodium leucotomos can be recommended to prevent PUVA-related skin damage.

A 2007 study involving 50 people with vitiligo vulgaris compared the effectiveness of oral Polypodium leucotomos extract (250 mg three times per day) combined with narrow-band ultraviolet B treatment (twice weekly for 25 to 26 weeks) to narrow-band UVB treatment and a placebo.

Researchers found an increase in repigmentation in the head and neck area in the polypodium group compared to the placebo group. This effect was more pronounced in people with lighter skin.

A 2014 literature review published in the Journal of Drugs in Dermatology confirms these results. However, more research is needed before recommending Polypodium leucotomos' for treating vitiligo.

Polypodium leucotomos extract is generally well tolerated and safe with few side effects, according to a 2015 study published in the Journal of Drugs in Dermatology. Side effects may include indigestion and skin itchiness.

People with allergies to ferns should avoid taking products containing Polypodium leucotomos. In addition, its safety in pregnant or nursing women, children, and people with liver or kidney disease isn't known. People with those conditions should speak to their doctor or pharmacist before using.

A related fern species, Polypodium vulgare, has been found to cause drowsiness. Theoretically, Polypodium leucotomos could have the same effect, so it may have an additive effect if taken with drugs that cause drowsiness, such as benzodiazepines lorazepam Ativan (lorazepam) or Valium (diazepam), some antidepressants, narcotics such as codeine, barbiturates such as phenobarbital, alcohol, and herbs that cause drowsiness, such as hops, valerian, kava, and chamomile.

Commercial extracts of Polypodium leucotomos have been available since the 1970s. It is sold primarily as a capsule and is found as an ingredient in many sun-blocking supplements.

Sometimes referred to as calaguala, Polypodium leucotomos supplements are available in natural food stores and online. There is currently no standard recommended dosage.

Dietary supplements are not regulated by the U.S. Food & Drug Administration. To ensure you are purchasing a quality Polypodium leucotomos supplement look for a trusted independent, third-party seal on the label, such as U.S. Pharmacopeia, NSF International, or ConsumerLab.

While the research is still inconclusive, extracts of the tropical fern show promise for preventing sunburn. Taking Polypodium leucotomos prior to sunbathing or spending time at the beach could theoretically slow tanning time. However, it is too soon to recommend using the plant before spending time in the sun.

In theory, Polypodium leucotomos should help to prevent wrinkles and other visible signs of sun-damaged skin, however, this has not been confirmed in clinical trials. The plant extract is rich in antioxidants, which are believed to prevent and reverse the signs of aging on the skin. In addition, laboratory research on skin cells suggests it can block sun damage. More research is needed to confirm this purported benefit.