The core ingredient of EstheShield is a proven natural fern extract, polypodium leucotomos. It is an effective chemophoto-protective agent that leads to a significant decrease of UV-induced erythema, sunburn cell formation, DNA damage, epidermal hyperproliferation, and dermal mast cell infiltration.The core ingredient of EstheShield is a proven natural fern extract, polypodium leucotomos.
Polypodium leucotomos has been extensively researched. Clinical studies show that polypodium extract is effective in defending skin against damage from UV radiation when taken orally. EstheShield is a high potency formulation (500 mg) designed to provide the highest level of protection.
Polypodium leucotomos has both antioxidant properties that help to inhibit free radicals in skin tissues from causing long-term DNA damage and photo-ageing.
Overall, 19 human and 6 basic science studies were included in this review spanning over 40 years of research from 1972 to 2014. Oral polypodium leucotomos was administered in daily doses ranging from 120 mg to 1080 mg. This review of literature has demonstrated that PLE is well tolerated at all doses administered.
Current level of evidence suggests that oral PLE is safe and can be prescribed confidently for long term use.1
Much of the research that has been done on polypodium leucotomos over the past 40+ years has been on its management of skin conditions and its photo-protective properties after it is ingested. Many of these clinical studies have shown extracts of polypodium leucotomos to be surprisingly effective at defending skin against damage from the sun (ultraviolet radiation) when polypodium leucotomos is taken orally, with some authors even calling it an “internal sunscreen.”
A 2010 publication reported the results of a clinical trial in which 10 healthy volunteers were given either 240mg oral polypodium leucotomos 8 hours and again 2 hours before UVA exposure, or not given anything at all before UVA exposure. Prior to exposure, each individual was measured to determine his or her baseline skin histology and how much UVA radiation it took to cause erythema (MED: minimal erythema dose). After exposure, skin samples were again taken and tested for CD (common deletion: a type of DNA damage and a marker of chronic UVA radiation). At 2 times the MED the non-PL group had increases of CD of 217% over baseline, while the group taking PL had decreases of 84%. At 3 times the MED, the non-PL group had increases of CD of 760% over baseline, while the group taking PL only had a 61% increase on average. These trends were determined “very strong” by the researchers, and while the data was not statistically significant (due in part to the small sample size), the researchers concluded that Polypodium leucotomos “may prevent UVA-induced skin photodamage possibly by preventing UVA-dependent mitochondrial DNA damage.” 2
In 2007, a study found that polypodium leucotomos extract was beneficial to individuals who are extremely sensitivity to the sun. The individuals all had either polymorphic light eruption (itchy red rashes from sun exposure) or solar urticaria (a form of hives caused by sunlight), but had not responded well to other available therapies. These patients’ response to sunlight was measured both before and after taking an oral dose of 480 mg of Polypodium leucotomos. The researchers reported that after taking Polypodium leucotomos and being exposed to sunlight, patients had a relevant and statistically significant reduction of skin reactions and subjective symptoms as compared to exposure without PL. The researchers concluded that the “photoprotective activity of Polypodium leucotomos was significant,” and furthermore, the tolerance of PL was excellent and administration was shown to be effective and safe. 3