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Astaxanthin: Queen of anti-aging antioxidants
Astaxanthin, a somewhat unpronounceable name, is a 100% natural anti-aging marvel. Extracted from the microalga Haematococcus pluvialis, astaxanthin is renowned for its antioxidant properties and specifically for the protection and health of the skin, eyes, and brain. Learn more about this queen of antioxidants.
Astaxanthin: introduction
Astaxanthin is a bright red pigment belonging to the carotenoid family, specifically xanthophyll carotenoids. Rare in the diet, it can nevertheless be found in krill, shellfish, or salmon, but its most concentrated natural source is the microalga Haematococcus pluvialis, which is why it is generally extracted from it to make dietary supplements.
Another specificity, thanks to a molecular structure containing a keto group and a hydroxyl group at each end, astaxanthin has unique characteristics that support its use in promoting human health [4].
In its natural state, the role of this pigment is to protect against UV radiation and stress. It is therefore an antioxidant particularly recognized for the skin and eyes in the context of protection related to the sun's UV radiation. Its very high antioxidant capacity would help limit the impact and damage on the dermis, prevent sunburn, and reduce signs of skin aging.
If astaxanthin seems to be a fabulous ally against the harmful effects of the sun, it is also an anti-aging molecule for many other systems in our body, notably vision, the brain, and the skin.
Astaxanthin: powerful antioxidant
Astaxanthin is said to be a powerful antioxidant, but what is an antioxidant and what is it for?
An antioxidant, a very trendy word in the world of cosmetics, health, and especially anti-aging, is a molecule that acts against the oxidation of our cells caused by free radicals. If these free radicals are too numerous, the body can no longer fight them and enters a state called oxidative stress, a state that accelerates body aging and cellular degeneration.
Astaxanthin is renowned for its antioxidant action, which seems to be largely superior to other carotenoids. It is even estimated to be 20x more potent than beta-carotene [1]. This superiority is thought to be due to its unique molecular structure: astaxanthin contains polar groups at each end of its molecule that fight free radicals and, in its central segment, double bonds that reduce harmful electrons [5].
Also, astaxanthin is considered one of the most powerful antioxidants, as it is believed to be able to reach both the inside and outside of cells, which would allow it to protect the entire cell against free radicals.
Ultimately, it is an antioxidant that has the particularity of not becoming pro-oxidant, unlike many antioxidants that convert in the human body into vitamin A (retinol), excess of which is dangerous.
Astaxanthin: brain protection
Among the organs and systems that decline with age, and that concern us, are the brain and cognitive functions.
Astaxanthin appears to act on cognitive functions by preventing or delaying certain neurodegenerative diseases. This is notably the case for cognitive decline and dementia, where inflammation and oxidative stress are pointed out by numerous studies [6]. Furthermore, several studies have evaluated the impact of astaxanthin on these functions through randomized double-blind trials [1]. A study involving people aged 45 to 64 complaining of forgetfulness showed that with a daily dose of 12mg, cognitive test results and maze learning improved [1]. Another study highlights, in people aged 45 to 64 without cognitive impairment, that a dose of 8mg/day significantly improves word recall compared to the placebo group [1].
It thus seems that astaxanthin helps protect the brain through its strong antioxidant and anti-inflammatory activity [1, 2] and would prevent memory deficits. Additionally, it would induce the proliferation of neural progenitor cells and promote neurogenesis and neuroplasticity [7], which decrease with age.
Astaxanthin: eye and vision health
Another concern that comes with age is vision.
Astaxanthin also appears to be protective of eye health, as it is known to prevent eye fatigue, dryness, sun sensitivity, as well as age-related macular degeneration (AMD) and cataracts [1, 2, 7]. These preventive effects could be related to its protective role on the lens [8] as well as its antioxidant properties that neutralize singlet oxygen and protect against photochemical damage [2].
Animal studies have also shown that astaxanthin helps protect against photokeratitis, cataract formation, and retinal lesions associated with increased intraocular pressure [1].
Astaxanthin: skin ally
When we talk about anti-aging effects, we often think of aspects related to beauty, aesthetics, and especially skin and wrinkles. Here again, astaxanthin stands out as an ally for healthy, protected, enhanced, and radiant skin.
Sun protection, anti-inflammatory, reparative, as well as hydration and collagen: explanations of anti-aging actions for the skin:
Protection against the harmful effects of the sun
Popular for a few years, frequently demonstrated by modern science [1, 2, 3, 9], astaxanthin is said to have protective properties against damage and aging caused by UV and sunburn.
Astaxanthin, like other carotenoids, has the particularity of having a molecular structure composed of at least ten conjugated double bonds, which offers a high potential for trapping reactive oxygen species (ROS), acting partly as protection against UV irradiation [2]. Partly, because it does not replace UV protection and sunscreen remains essential.
Astaxanthin helps prepare the skin and better tolerate sun exposure through several actions:
- Prevent skin photoaging
- Fight oxidative stress caused by UV
- Prevent sunburns – the famous “sunburns”
- Strengthen skin pigmentation
- Improve sun tolerance and prevent lucites – sun allergies that particularly affect women
- Provide additional protection to the skin and eye tissues that are in direct contact with light
It also promotes tanning because it has the property of stimulating melanin production, the pigment that colors the skin.
For more information on astaxanthin's action against the sun, consult our article.
Anti-inflammatory support
Redness and sensitivity are often the result of chronic skin inflammation caused by continuous oxidative stress [4]. Astaxanthin can act as an inhibitor of the inflammatory effects of UV radiation by reducing the production of reactive nitrogen species, the expression of inflammatory cytokines, and apoptosis (cell death) in the epidermis [9]. Thus, it can relieve these inflammatory symptoms [3, 9], and it has also been extensively studied in the development of treatments for psoriasis and atopic dermatitis [4].
Skin repair
As we age, we become more sensitive to photoaging, which can lead to increased production of ROS (reactive oxygen species). These ROS can stimulate the synthesis of MMPs (matrix metalloproteinases) responsible for degrading the extracellular matrix and collagen, resulting in thinner, more fragile skin and slower epithelialization [3].
Studied for about ten years in skin repair and healing, astaxanthin appears to reduce cellular damage caused by free radicals and MMPs, increase dermis thickness, and help improve wound healing [1, 3].
Anti-skin aging
"Last but not least," astaxanthin helps maintain good skin health, enhances its beauty, and prevents skin aging.
Astaxanthin stimulates skin hydration, tone, and elasticity as well as collagen production [3, 10]. Through these anti-aging effects, it prevents the appearance of wrinkles, hyperpigmentation, and sun or age spots [1, 3], a symbol of skin aging.
"Several studies support these results:"
- "A human clinical study demonstrated that oral intake of astaxanthin over 8 weeks had effects on skin wrinkles (crow's feet), the size of age spots, elasticity, texture, and skin hydration [10]."
- "A study conducted in 2020 shows that astaxanthin increases dermal hydration by enhancing the activity of aquaporin-3 (AQP3), a water channel involved in skin hydration [11]."
- "Several studies show that a dose of astaxanthin between 6 and 12 mg/day can increase skin elasticity and its hydration level, as well as improve skin texture [1]."
"Powerful antioxidant action, brain protection, eye health, and skin ally: astaxanthin is a true anti-aging ally to preserve the youthfulness of the body."
"Sources"
[1] Ash, Michael. "Astaxanthin: The Key to a New You."
[3] "Astaxanthin: The antioxidant queen of skin care."
[4] Davinelli, S., Nielsen, M. E., & Scapagnini, G. "Astaxanthin in Skin Health, Repair, and Disease: A Comprehensive Review. " Nutrients. 10(4) (2018): 522.
[5] Higuera-Ciapara, I., Félix-Valenzuela, L., & Goycoolea, F. M. "Astaxanthin: a review of its chemistry and applications. " Critical reviews in food science and nutrition. 46(2) (2006): 185–196.
[6] Padurariu M, et al. "The oxidative stress hypothesis in Alzheimer’s disease. " Psychiatr Danub. 25(4) (2013): 401-9.
[7] Grimmig B, et al. "Neuroprotective mechanisms of astaxanthin: a potential therapeutic role in preserving cognitive function in age and neurodegeneration. " Geroscience. 39(1) (2017): 19-32.
[8] Yang, M., Chen, Y., Zhao, T., & Wang, Z. "Effect of astaxanthin on metabolic cataract in rats with type 1 diabetes mellitus." Experimental and Molecular Pathology, 113 (2020).
[9] Yoshihisa, Y., Rehman, M. U., & Shimizu, T. "Astaxanthin, a xanthophyll carotenoid, inhibits ultraviolet-induced apoptosis in keratinocytes." Experimental dermatology, 23(3). (2014): 178–183.
[10] Tominaga, K., Hongo, N., Karato, M., & Yamashita, E. "Cosmetic benefits of astaxanthin on humans subjects." Acta biochimica Polonica. 59(1) (2012): 43–47.
[11] Ikarashi, N., Kon, R., Nagoya, C., Ishikura, A., Sugiyama, Y., Takahashi, J., & Sugiyama, K. "Effect of Astaxanthin on the Expression and Activity of Aquaporin-3 in Skin in an In-Vitro Study." Life (Basel, Switzerland), 10(9) (2020).
