The skin care industry generated over $5.6 billion in sales in 2018 alone. The brands marketed as “natural” contributed significantly to market growth. In particular, plant oils, extracts and dietary supplements have been used as natural sunscreens or replacements for themconventional sun protection products, advertised. But is natural sun protection really effective? The Examine.com team took a closer look at this question. Their analysis is evidence-based and contains 42 unique references to scientific papers.
Natural sunscreen vs. sunscreens
It has been shown that natural sunscreens (including supplements and plant oils) alone are not sufficiently effective in protecting your skin from the harmful effects of the sun. Some can be combined with proven sun protection methods (sunscreen, clothing, shade) to provide additional sun protection. However, none of these methods should be used as a replacement for sunscreen.
Ultraviolet radiation can damage skin and eyes
Excessive unprotected exposure to solar radiation can promote skin aging and skin cancer. Particularly dangerous is ultraviolet sunlight (UV spectrum), whose wavelength is shorter than that of visible light but longer than that of X-rays.
UVA and UVB radiation in particular can cause skin damage. UVA accounts for more than 90 percent of the solar radiation on the Earth's surface, and UVB only about 5%. Together they can cause sunburn, DNA damage and accelerate skin aging.
When used correctly and consistently, sunscreens can prevent sun-induced skin aging (i.e. photoaging) and reduce the risk of skin cancer.
Are plant oils effective as natural sun protection?
In general, it is recommended to use a broad-spectrum sunscreen (i.e. UVA + UVB protection) with a sun protection factor (SPF) of at least 30, or higher if your skin burns easily. So are natural plant oils suitable for this challenge? In short, not really. At least not for yourself.
When tested only for protection against UVB radiation, many vegetable oils have a sun protection factor of <8. These oils can be incommercially available sunscreenscan be incorporated to improve the overall sun protection factor, but alone they are not sufficient for UV protection.
Reliability can also be an issue when making natural sunscreen alternatives at home. Sunscreens are formulated using specific ingredients in specific amounts, and manufacturing processes are used to ensure that these UV-protecting ingredients are evenly distributed throughout the sunscreen. This process is difficult to replicate at home.
A small warning note: Some of these vegetable oils may cause allergic reactions or skin irritation. These reactions can range from mild to severe.
Sun protection factor (SPF) of vegetable oils
In most cases, only protection against UVB radiation is taken into account during examinations. When SPF is measured against both UVB and UVA radiation, these values are even lower. For example, coconut oil offers an SPF of 7 for UVB rays only, but an SPF of ≤1 against UVA + UVB.
Vegetable oils alone should not be used as a replacement for sunscreen as they do not provide adequate protection. However, they can be used as an ingredient in some sunscreens to increase SPF.
Natural sun protection from within: Can dietary supplements protect you?
Cocoa
When using specially processed high-flavanol cocoa powder or chocolate, three randomized controlled trials (RCTs) found a modest improvement in skin resistance to UV damage after 6 weeks of supplementation. Almost all participants were womenwith Fitzpatrick skin type II or III.The results are promising and fairly consistent across all existing studies. However, further research is required.
Polypodium leucotomos
Polypodium leucotomos is a South American fern species in the family Polypodiaceae. In both animal and human studies, Polypodium leucotomos has demonstrated the ability to reduce UV-induced skin cell damage, DNA damage, and oxidative stress. Only in human studies, both short (<1 week) and long-term (1 to 3 months), were the results consistent.
One limitation is that almost all of these studies were conducted in people with Fitzpatrick skin types I to III. The effects of P. leucotomos on skin types IV to VI have not yet been sufficiently investigated.
A small warning note: The estimated SPF protection of P. leucotomos is about 4. It is well below the recommended level of at least 30. It should not be used as an alternative to sunscreen.
Astaxanthin
Astaxanthin, a powerful antioxidant, may help reduce DNA damage caused by UV radiation. However, the research results so far have been incomplete and not of very high quality. Better research is needed before firm conclusions can be drawn about its effectiveness.
Two promising human studies examined a combination of rosemary and grapefruit extracts as a natural sunscreen.
The first was a small pilot study with 10 subjects and the second was a follow-up study in which 90 subjects were randomized. In both studies, the combination was able to increase UV tolerance and reduce markers of oxidative damage in the skin.
Despite the promising results, no firm conclusions can yet be drawn from these limited data.
Vitamin E
While animal and cellular studies have shown that vitamin E provides natural sun protection, human studies have shown mixed (but promising) results - for both topical applications and oral supplementation.
Another problem: Many studies have tested vitamin E as part of a multi-ingredient formula, making it very difficult to say what effect this vitamin might have when used alone.
What about sunscreens labeled as “natural”?
The terms “natural” and “organic” do not guarantee any advantage over conventional sun protection products. The inclusion of these terms in the label does not always mean that the product is safer for consumers than products that do not contain these labels.
However, there are two natural sunscreen ingredients that are often used in natural cosmetics and have proven to be effective - zinc oxide and titanium dioxide. Often called mineral sunscreens, these compounds can reflect and disperse UV rays.
Conclusion
There is no vegetable oil or extract that can replace a high SPF sunscreen. Vegetable oils can be combined with sunscreen creams to increase their overall effectiveness. However, it should be noted that they can also cause allergic skin reactions or inflammation in some people.
Dietary supplements should not be used alone as a sunscreen alternative. Of the supplements studied, Polypodium leucotomos has the strongest evidence of a possible synergistic effect when used in conjunction with sunscreen or other sun protection methods.
