Life Extension Magazine®

Woman in pool preventing UV damage with oral sunscreen

Oral Sunscreen Provides All-over Protection

Topical sunscreens do not protect all parts of the body from solar radiation. A fern extract and other nutrients taken orally help block UV damage to skin cells, decreasing DNA mutations by 84% and supporting DNA repair.

Scientifically reviewed by Dr. Gary Gonzalez, MD, in August 2023. Written by: Michael Downey, Health & Wellness Author.

For decades, we’ve been told how to protect our skin against the damaging effects of the sun:

Always wear sunscreen outdoors!

That’s good advice but it is not a perfect solution. Topical sunscreens must be spread over every exposed area to be effective, they must be reapplied regularly, and they can stain clothing.

Scientists have identified a tropical fern extract called Polypodium leucotomos that, when taken orally, works deep inside skin cells to reduce the harmful effects of ultraviolet light.

In fact, Polypodium-supplemented participants demonstrated a striking 84% decrease in DNA mutations when exposed to ultraviolet light.1

Researchers have combined Polypodium leucotomos with two other protective compounds, nicotinamide and red orange extract, offering superior protection from sun damage not available from using sunblock alone.

Protection against Ultraviolet Radiation

Man sitting in the sun

Ultraviolet (UV) radiation damage to DNA is the main cause of skin cancer, and the primary culprit in skin photoaging.2-4

There are multiple reasons UV radiation does so much damage. For one thing, UV radiation from the sun appears to stimulate the most intensive free-radical formation.5 UV radiation also stimulates reactions that can increase mutations and alter DNA itself.6

These reactions alter a vital tumor-suppressor gene called p53. We know that p53 is critical for DNA repair and for programmed cell death (apoptosis) when DNA damage is beyond repair.7-9

UV radiation also inhibits production of ATP (adenosine triphosphate), which is required in order to whisk away damaged DNA segments.10-13

Wearing sunscreen is vitally important. But it doesn’t provide total protection from ultraviolet rays. It doesn’t usually protect the scalp or eyelids, it may come off with perspiration or swimming, and most people don’t use nearly enough, or reapply it frequently enough, to block the sun’s harmful rays. UV rays can even penetrate some fabrics to reach parts of the body covered by clothing.14

Since protection against UV radiation is never absolute, scientists recognized that it is important to find a way to promote prompt DNA repair in order to prevent malignant transformation in skin cells.15,16

Researchers focused on Polypodium leucotomos, a tropical fern native to Central and South America. It has been used to treat psoriasis and other skin conditions.1 Because it is taken orally, it protects all skin areas evenly and won’t wash or rub off.

Research has found that it has an ability to protect and repair DNA. Polypodium leucotomos extract is rich in polyphenols that inhibit oxidative stress and inflammation, while protecting skin cells against DNA damage caused by UV radiation.1

Through all these mechanisms, this plant extract delivers a powerful internal defense against ultraviolet radiation.

Results of Clinical Studies

Scientists enlisted healthy volunteers, aged 29 to 54, for a clinical study. The individuals were divided into control and treatment groups and the treatment participants were given two 240 mg doses of Polypodium leucotomos extract orally. All subjects were then exposed to ultraviolet-A radiation (UVA), first at a low exposure level and then at a higher level.1

After low-level UVA exposure, scientists found that placebo participants had a 217% increase in damaging DNA mutations. By contrast, the Polypodium-supplemented participants had a striking 84% decrease in these mutations.1

Following high-level UVA exposure, DNA mutations in the placebo group increased by a startling 760%. However, DNA mutations in the Polypodium-supplemented group increased by only 61%.1

Since DNA mutations are the main cause of prematurely aged skin and skin cancer,4,6,11,17,18 this level of DNA protection against ultraviolet exposure has enormous potential benefits.

This strong level of sun defense has been further increased. Researchers have combined the fern extract Polypodium leucotomos with two additional protective ingredients: nicotinamide and red orange extract for enhanced skin protection.

What you need to know

Prevent UV-Radiation-Induced Damage

  • Photoaging and skin cancer are caused in large part by ultraviolet radiation, but topical sunscreens can wear off with perspiration, stain clothing, and leave some areas unprotected.
  • Research shows that a tropical fern extract called Polypodium leucotomos, when taken orally, reduces the harmful effects of solar radiation. It helps prevent cell damage and supports DNA repair, inhibiting cancer risk and skin aging.
  • The addition of nicotinamide and red orange extract further boosts sun protection, and all three ingredients work together from the inside out to provide protection that won’t rub or wash off.
  • For optimal sun exposure protection, this potent defense should be combined with a high-quality, high-SPF topical sunscreen.

Benefits of Nicotinamide

Two recent studies summarized the ability of nicotinamide to prevent UV-light-induced skin cancer. This form of vitamin B3 has been shown to:19,20

  • Enhance DNA repair,
  • Modulate production of inflammatory proteins called cytokines,
  • Reduce UV-induced immunosuppression of skin responses,
  • Regulate skin barrier function, and
  • Restore cellular energy levels after UV exposure.

UV radiation reduces the production of ATP, the cellular energy that the body needs to support DNA repair. Nicotinamide helps solve this problem by preventing loss of ATP in cells.12 Nicotinamide can also be made into nicotinamide adenine dinucleotide (NAD+), a key compound that helps the body make ATP.21

To verify these effects, scientists pretreated skin cells with nicotinamide and exposed them to UV radiation. The nicotinamide enhanced the removal and replacement of damaged DNA and significantly increased the number of cells undergoing DNA repair.21

Another clinical trial showed that nicotinamide protects against UV-induced immune suppression.22

These dual benefits—repairing DNA and inhibiting immune suppression—contribute to nicotinamide’s protection against the sun’s damaging

Scientists conducted a clinical study on 386 healthy individuals who had been diagnosed with at least two non-melanoma skin cancers within the last five years, which placed them in a “high-risk” category. After taking 500 mg of nicotinamide twice daily for 12 months, the rate of new, non-melanoma skin cancers was reduced overall by 23%, compared to the control group.23

Red Orange Extract

Red Oranges

Red orange extract provides further protection against UV-induced inflammation and oxidative stress. Obtained from three pigmented varieties of sweet oranges (Citrus sinensis), its benefits result from high levels of three natural compounds with powerful antioxidant effects: anthocyanins, flavanones, and hydroxycinnamic acids.24-27

In a lab study, researchers applied red orange extract to human keratinocytes, the most common type of cell in the epidermis, the outermost layer of our skin. Then they exposed these treated cells to UV radiation, and they observed that the extract significantly reduced cell damage, inflammation, and cell death.25

Scientists then moved on to human studies of red orange extract’s protection against UV radiation. Oral supplementation with the extract was demonstrated to reduce sunburn intensity by about 35%.28 The amount of lifetime sun exposure and the number of lifetime severe sunburns is closely correlated with the development of skin cancers, so this protection is extremely significant.29-31

In another clinical study, researchers demonstrated that red orange extract protects against UV-induced photoaging. For 15 days, volunteers took red orange extract and were exposed regularly to a solar lamp. The extract reduced UV-induced sunburn, as well as age-spot pigmentation, and decreased melanin content from 27% to 7%.32

The study concluded that red orange extract can lead to an improvement in skin appearance and can protect the skin from harmful sun damage.32


Family playing in the sun

Photoaging and skin cancer can result from exposure to solar ultraviolet radiation.

Topical sunscreens seldom protect eyelids and other exposed skin, they wear off with perspiration or swimming, and they can stain clothing.

Research shows that a fern extract called Polypodium leucotomos, taken orally, inhibits cell damage and supports DNA repair, two key mechanisms that lower cancer risk and help prevent premature skin aging.

Adding nicotinamide and red orange extract offers a greater level of sun protection.

Supplementation with these three ingredients ensures evenly distributed skin protection from the inside out, that doesn’t rub or wash off.

Combined with a high-quality, high-SPF topical sunscreen, this oral supplement provides a potent defense against sun damage.

If you have any questions on the scientific content of this article, please call a Life Extension® Wellness Specialist at 1-866-864-3027.


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