Sunscreen technology has evolved significantly in recent years, moving beyond simple UV filters. A key development in modern sun protection is the inclusion of antioxidants in sunscreens. While UV filters provide the primary defense against harmful rays, antioxidants in sunscreens work on a cellular level to combat the subtle damage that can occur despite our best sun protection efforts. Look into my UV index guide and learn best practices about when to protect yourself from the sun.
The first part of our European sunscreen ingredients series went deeper into the different Sunscreen filters that protect our skin against UV and Visible Light.
In this second part of our European sunscreen ingredients series, we’ll explore:
- The role of antioxidants in sunscreens which enhance sun protection
- Key antioxidants found in European sunscreens
- Innovative ingredients like marine-derived MAAs
- Other promising antioxidants in sunscreens
Recent research indicates that sunscreens formulated with antioxidants offer more comprehensive protection against sun-induced skin damage. Let’s examine the science behind antioxidants in sunscreens and how they contribute to defending your skin against harmful UV rays.
The Power of Antioxidants in Sunscreens: A Deep Dive
According to the paper from 2023 “Antioxidants in Sunscreens: Which and What For?” by Jesus et al. the mechanisms of action of antioxidanta in sunscreens are:
- Radical Scavenging
- All antioxidants act as radical scavengers, neutralizing UV-induced Reactive Oxygen Species (ROS) and Reactive Nitrogen Species (RNS), thus reducing oxidative stress. But different antioxidants target specific molecules:
- Hydroxyl radical: Neutralized by oxothiazolidine, ectoin, vitamin C, and ferulic acid (and their derivatives)
- Superoxide anion: Targeted by oxothiazolidine, vitamin C, and ferulic acid (and their derivatives)
- Hydrogen peroxide: Scavenged by oxothiazolidine and vitamin C
- Peroxyl radicals: Neutralized by vitamins E and C, ferulic acid (and their derivatives)
- Peroxynitrite anion: Targeted specifically by vitamin C
- Singlet oxygen: Neutralized by ectoin and vitamin C
- Reactive aldehydes: Scavenged by oxothiazolidine
- Boosting Antioxidant Levels
- Some antioxidants go beyond neutralizing free radicals – they actually increase the levels of antioxidants in our skin’s enzymatic and non-enzymatic systems. Key players here include vitamin E and its derivatives, ectoin, and niacinamide.
- DNA Repair Activation
- Oxothiazolidine, ectoin, and niacinamide take protection a step further by activating DNA repair mechanisms in both epidermal and dermal skin cells.
- Immunoprotection
- Vitamins E and C, oxothiazolidine, and niacinamide have been shown to inhibit immunosuppression processes induced by UV exposure. Additionally, vitamin C and ectoin help prevent the decrease in Langerhans cells, crucial components of our skin’s immune system. UV radiation is (amongst other negative effects of UV) supressing our immune system and you can deep dive into these effects by reading my first ever blog post.
- Anti-Inflammatory Action
- Ferulic acid and ectoin shine in their ability to reduce the release of pro-inflammatory interleukins. Meanwhile, vitamins E and C, along with oxothiazolidine, help decrease metalloproteinases, enzymes that can break down skin structure when overactive.
- Pigmentation Control
- For those battling hyperpigmentation, ferulic acid and niacinamide offer hope through their ability to inhibit tyrosinase, a key enzyme in melanin production.
- Sunburn Cell Reduction
- Even if sun damage occurs, antioxidants can help mitigate the effects. Vitamins E and C are particularly effective at decreasing the impact of sunburned cells.
- The Multifunctional Nature of Antioxidants
- It’s crucial to understand that all antioxidants possess a multifunctional mechanism of action. They don’t just perform one role but work in various ways to protect and repair our skin.
A Note on Comparative Efficacy
While we know a lot about how these antioxidants work, there’s still more to learn. The absence of comparative studies regarding the potency of these compounds means we can’t definitively say which antioxidant is the most potent or effective. Each contributes to skin health in its unique way.
Key Antioxidants in Sunscreen Formulations
- Vitamin E – found in over 66% of sunscreens
- Forms: tocopherol, tocopheryl acetate and tocopheryl glucoside
- Vitamin C – found in 12.9% of sunscreens
- Forms: ascorbic acid, ascorbyl palmitate (most common vitamin C derivate in sunscreens), tetrahexyldecyl ascorbate (found in high-end sunscreens)
- Oxothiazolidine– found in 4-7% of sunscreens
- Ferulic Acid – found in 4-7% of sunscreens
- Forms: ferulic acid, ethyl ferulate and ethylhexyl ferulate
- Ectoin – found in 4-7% of sunscreens.
- Ectoin is a surprisingly well-researched, multi-functional active that protects from pollution & light protection to skin hydration, soothing, and barrier repair, several things to your skin.
- It is a small stress-protection molecule that protects microorganisms living under extreme conditions such as salt lakes, hot springs, arctic ice, the deep sea, or deserts. It was discovered in 1985 in a microorganism living in a salt lake in the Egyptian desert.
- Niacinamide (Vitamin B3) – found in 4-7% of sunscreens
For example Untrasun Sunscreen contains antioxidants like Ectoin, Vitis Vinifera Seed Extract (grape seed extract), Vitamin E (tocopheryl acetate and tocopherol) and Vitamin C (ascorbyl tetraisopalmitate).
Natural Sunscreen Antioxidants: Beyond the Basics
MAAs: Nature’s Answer to Sunscreen
MAAs (Mycosporine-like Amino Acids) are UV-absorbing compounds found in various marine and freshwater organisms. These colorless, water-soluble molecules have evolved to protect aquatic life from harmful UV radiation.
Here is a summary of the papers from Rosic et al. (2019) and Singh et al. (2021) examining Mycosporine-like Amino Acids:
Key Benefits for Skincare:
- Broad Spectrum UV Protection: MAAs absorb both UVA (315-400 nm) and UVB (280-315 nm) radiation without producing free radicals.
- Antioxidant Powerhouses: MAAs, especially mycosporine-Gly, have shown incredible antioxidant properties – even outperforming vitamin C in some studies.
- Inflammation Fighters: MAAs have shown promise in reducing inflammation, which is great news for those with sensitive or acne-prone skin.
- Anti-Aging Marvels: MAAs may help prevent collagen destruction and maintain elastin content in the skin.
- Wound Healing Support: Some MAAs can promote cell proliferation and wound healing, helping your skin recover faster.
- Environmentally Friendly: As natural compounds, MAAs are biodegradable and don’t harm marine ecosystems like some other sunscreens.
- Photostability: Unlike some chemical UV filters, MAAs remain stable under UV exposure.
- Enhancing Stability and Effectiveness: Recent research has shown that MAAs can be combined with other natural compounds to increase their stability and effectiveness. For example:
- MAAs grafted onto chitosan (a natural polymer) showed increased efficacy against both UV-A and UV-B radiation.
- A combination of porphyra-334, shinorine, and mycosporine-serinol showed SPF values comparable to synthetic sunscreens.
The Science Behind MAAs:
- Over 30 different MAA compounds have been identified in nature.
- Common MAAs include mycosporine-glycine, shinorine, and porphyra-334.
- Their effectiveness varies based on their specific chemical structure.
The Future of MAAs:
While MAAs are already being used in some sunscreen products, there’s growing interest in developing more MAA-based skincare solutions.
Some MAA-based products are already hitting the market:
- Helioguard®365: A natural UV-screening active containing red alga porphyra umbilicalis. It’s shown to improve cell viability and reduce DNA damage from UV-A radiation.
- Helionori®: also prepared from the red seaweed porphyra umbilicalis known as “nori” in Japan.
While more research is needed, these natural compounds are showing immense promise in the world of skincare. They offer a unique combination of UV protection, anti-aging benefits, and eco-friendliness that could revolutionize our approach to sun care.
Other Antioxidants in Sunscreens
In 2021 Guan et al. published the paper “Sunscreens and Photoaging: A Review of Current Literature”. Here is a summary of lesser known antioxidants mentioned in this paper:
- Plants:
- Soy extracts
- A study of 68 people found that soy moisturizers with special inhibitors significantly improved skin tone, texture, and appearance.
- Polyphenols
- found in tea leaves, grape seeds, and pomegranate
- In one study, sunscreen with tea extracts better shielded skin against sun damage than sunscreen alone.
- Green tea extract combined with resveratrol
- might even boost your sunscreen’s SPF! More research is needed, but it’s a promising combo.
- Soy extracts
- Melatonin:
- Not just for sleep! Melatonin is a triple-threat antioxidant that scavenges free radicals, reduces their production, and boosts your skin’s natural defenses.
- Lab studies show it can help with DNA repair and protect against both UVA and UVB damage.
- It’s been shown to protect against sun-induced redness and activate enzymes that fight oxidative stress.
- Polypodium Leucotomos Extract (PLE):
- This tropical fern extract is a multitasking marvel with antioxidant, chemoprotective, and anti-inflammatory properties.
- In a study of 22 people, oral PLE reduced UVB-induced redness within just 2 hours.
- Another study found that taking 480 mg of PLE daily significantly decreased persistent pigment darkening and delayed tanning.
- Topical PLE has shown promise in lab studies, reducing sun damage in reconstructed human skin models.
- Photolyase:
- These unique enzymes can actually repair DNA damage caused by UV radiation.
- They work by using energy from UV light to break harmful bonds in damaged DNA.
- When added to SPF 50 sunscreen with antioxidants, photolyases significantly reduced signs of photoaging compared to sunscreen alone or sunscreen with just antioxidants.
Conclusion: Understanding Antioxidants in Sunscreens
Our exploration of antioxidants in European sunscreens has revealed crucial information for making informed choices. Key takeaways:
- Mechanisms of action: Antioxidants in sunscreens primarily work through radical scavenging, boosting antioxidant levels, activating DNA repair, providing immunoprotection, and offering anti-inflammatory action.
- Key players: Vitamin E (in over 66% of sunscreens), Vitamin C (12.9%), and compounds like oxothiazolidine, ferulic acid, ectoin, and niacinamide (4-7% each) are the most common antioxidants in European sunscreens.
- Innovative ingredients: MAAs (Mycosporine-like Amino Acids) from marine sources offer promising broad-spectrum UV protection and potent antioxidant properties.
- Emerging antioxidants: Compounds like polypodium leucotomos extract and photolyase are showing potential in enhancing sun protection and repairing UV damage.
Understanding these aspects helps in:
- Recognizing effective antioxidant combinations in sunscreen formulations.
- Appreciating the value of both established and innovative antioxidant ingredients.
- Making informed decisions about sunscreen choices based on scientific evidence rather than marketing claims.
This knowledge empowers us to select sunscreens that offer comprehensive protection without unnecessary additives, aligning with principles of effectiveness and minimalism in skincare.
References
Guan LL, Lim HW, Mohammad TF. Sunscreens and Photoaging: A Review of Current Literature. Am J Clin Dermatol. 2021.
Jesus A, Mota S, Torres A, Cruz MT, Sousa E, Almeida IF, Cidade H. Antioxidants in Sunscreens: Which and What For? Antioxidants (Basel). 2023.
Rosic NN. Mycosporine-Like Amino Acids: Making the Foundation for Organic Personalised Sunscreens. 2019.
Singh A, Čížková M, Bišová K, Vítová M. Exploring Mycosporine-Like Amino Acids (MAAs) as Safe and Natural Protective Agents against UV-Induced Skin Damage. 2021.