During virus infections, diabetes, cancer, cardiovascular diseases, and neurodegenerative diseases, reactive oxygen species play a significant role in the inflammatory response and cytokine outbreak that causes a wide range of clinical manifestation in the human body. To further explain, oxidative stress is linked with the development of multiple age-related diseases, like cancer and neurodegenerative diseases, and multiple other common diseases such as ischemia-reperfusion injury, stroke, hypertension, heart failure, atherosclerosis, diabetes, rheumatic diseases, and Alzheimer disease. Hence, in order to treat and control these diseases, antioxidants are an important medicine that science must explore. 

There are multiple different antioxidants available naturally and commercially. Ascorbic Acid (Vitamin C) and Carotenoids are one of them. Carotenoids are present in many fruits and vegetables. It consists of more than 600 lipid-soluble plant pigments and a few water-soluble carotenoids. It includes α-carotene, β-carotene, lycopene, β-cryptoxanthin, lutein, zeaxanthin, and astaxanthin. Vitamin C, also known as ascorbic acid and ascorbate, is a vitamin found naturally in various foods and sold as a dietary supplement. It is an essential nutrient involved in the repair of tissue and enzymatic production of neurotransmitters. It is also important in the functioning of multiple enzymes involved in the immune system. Both Vitamin C and Carotenoids neutralize free radicals effectively and are used in order to prevent and cure oxidative stress related diseases. 

Astaxanthin (ASX) is naturally produced by a wide array of microorganisms such as bacteria, microalgae, and yeasts. The alga Haematococcus pluvialis is the most promising source of the secondary metabolite. According to the study of Lim et al. in 2017, ASX has a range of benefits such protecting against the harmful effects of ultraviolet (UV) light, boosting immune response, improving reproductive capacity, enhancing stress tolerance, and fighting against oxidation of cells. More so, because it shares several metabolic and physiological functions linked to carotenoids, it is true that ASX has anticancer, antidiabetic, anti-inflammatory, and antioxidant activities as presented in the study of Yuan et al. in 2010. Humans cannot synthesize astaxanthin in the body. Like all other carotenoids, astaxanthin is absorbed alongside fatty acids via passive diffusion into the intestinal epithelium.

Studies recommended intake of Astaxanthin 2-4 mg per day together with foods rich in omega-3 such as chia seeds, flaxseed, fish, nutella, walnuts and almonds. Available forms of Astaxanthin products in the market are in the form of capsule, soft gel, tablet, powder, biomass, cream, energy drink, oil and extract. More so, it is good to note that no adverse effects were found with daily administration of astaxanthin (6 mg/day) in humans. 

Health Benefits of Astaxanthin 

As stated above, there are multiple health benefits with constant and daily intake of Astaxanthin. It has anticancer, antidiabetic, anti-inflammatory, and antioxidant activities. In recent days, more people are recognizing these benefits and more researches are evaluating the vast health advantage Astaxanthin can offer. Astaxanthin has superior benefits compared to other antioxidants like vitamin C. Hence, in order to explain further, here is a list of Astaxanthin benefits that make it more advantageous than its other counterparts:

  1. Astaxanthin helps in improving Skin Health

Astaxanthin can reduce the appearance of fine lines and wrinkles, improve skin elasticity, prevent age spots and hyperpigmentation, and protect from harmful ultraviolet rays of the sun. It has been termed as an internal sunscreen for it reduces inflammation and UV damage to the skin cells through acting as a potent ultraviolet radiation absorber. Astaxanthin blocks a certain amount of the ultraviolet radiation acting directly on the skin. It also neutralizes the free radicals induced by the UV radiation. It also inhibits the harmful enzyme production of the skin when exposed to UV light. Studies show that astaxanthin can improve skin conditions in all layers of the skin which includes the basal, dermal, and epidermal layers. When combined with retinol, there is significant reduction of aging appearance of the skin. Hence, it was proven in studies that Astaxanthin is 100 times stronger than beta carotene and 1000 times stronger than lutein in preventing UV light-induced skin damage. 

  1. Astaxanthin aids in relieving Pain and Inflammation

Astaxanthin has strong anti-inflammatory and pain reliever qualities. It reduces inflammatory compounds through blocking different chemicals in the body that produces the symptom of pain and inflammation. Just like commercially available analgesics, it blocks enzymes that cause chronic diseases. However, because of its naturally produced by organisms, there is significantly reduced risk for addiction, gastrointestinal bleeding, or liver and kidney problems. Studies have shown that it has potent activity against COX2 which is an enzyme that causes the production of inflammatory and pain mediators. Moreover, it also suppresses the levels of nitric oxide, interleukin 1B, prostaglandin E2, C Reactive Protein, and Tumor Necrosis Factor alpha, all of which has significant effects on the inflammatory cascade and progression of chronic diseases. 

  1. Astaxanthin helps in improving Eye Health

Oxidative stress has wide effects on the eyes. It can cause eye-related macular degeneration which is the most cause of blindness and even cause inflammatory eye conditions. Astaxanthin, as a natural antioxidant, has been proven to cross the blood retinal barrier, hence can reduce significant levels of reactive oxygen species in the eyes and protect it from these illnesses. Studies have also proven that astaxanthin protects the eye against eye fatigue, improves visual activity, and depth perception, and increases blood flow to eye tissues. It has also been observed that daily intake of Astaxanthin has protective effects against cataract formation, glaucoma, macular degeneration, and even blindness, promoting an overall better eye health. 

  1. Astaxanthin helps with Diabetes 

Patients with Diabetes usually have a higher concentration of reactive oxygen species in the body due to a reduced clearance capacity, hyperglycemia, and glucose toxicity. This causes an increased oxidative stress to pancreatic beta cells. This in turn causes pancreatic cell death and/or malfunction.  Studies have shown that Astaxanthin has antioxidant properties that can aid in protecting pancreatic beta cells through reducing oxidative stress and glucose toxicity in the blood. It also has the ability to help lower high blood pressure and improve glucose metabolism in patients diagnosed with type 2 diabetes mellitus. Moreover, Astaxanthin increases insulin sensitivity in these patients aiding in the better control of the disease and symptom management. 

  1. Astaxanthin reduces the risk for cardiovascular disease

Studies have proven that Astaxanthin helps in removing bad cholesterol. High Low Density Lipoprotein (LDL), also known as bad cholesterol, and low High Density Lipoprotein (HDL), also known as good cholesterol, in the body is a major risk factor in developing cardiovascular disease secondary to atherosclerotic plaque formation. Astaxanthin reduces the levels of LDL or bad cholesterol. There is also significant reduction in oxidative stress levels. It also promotes the production of adiponectin and HDL or good cholesterol. Increased levels of these reduces the risk for cardiovascular disease. It can also improve blood flow and circulation and thickness and elasticity of the wall of arteries. Hence, it can aid people with dealing high blood pressure, reducing their risk for heart failure due to hypertension. Recent studies have shown that daily Astaxanthin intake can reduce blood oxidation and delay blood clotting.

  1. Astaxanthin prevents and treats Fatty Liver Disease

Fatty liver disease occurs largely due to oxidative stress caused by prolonged inflammation in the liver. It is often associated with metabolic disorders like obesity and accumulation of lipids at the cellular level. It is proven that Astaxanthin can prevent and treat fatty liver disease through acting as an antioxidant which stays on top of oxidative stress in the liver. It helps restore normal liver function and avoid liver damage by getting rid of excess radicals caused by metabolic disorders.  Astaxanthin also has the ability to protect the liver function and prevent liver disease independent of its antioxidant properties. It has also been shown that Astaxanthin is effective against alcoholic fatty liver disease through the regulation of gut bacteria.

  1. Astaxanthin can reduce growth of Cancer cells

Astaxanthin has been found out to have some anticancer potential. Due to its notable activity against reactive oxygen species, researchers have proven that it can help in treating different types of cancer and aid in the therapy process of patients. Scientists discovered that astaxanthin has both short-term and long-term benefits as far as treating breast cancer is concerned. More specifically, they found that the antioxidant helps tame the growth of cancerous breast cells through exerting in activity such as antiproliferative, anti-apoptosis and anti-invasion, via different molecules and pathways including signal transducers and activator of transcription 3(STAT 3), nuclear factor Kappa light chain enhancer of activated β-cell (NF-Kβ), and peroxisome proliferator activator receptor gamma (PPAR-γ),and other multiple mechanism of cancer effects. However, the exorbitant cost associated with purifying astaxanthin has limited its use in cancer treatment. Administration of astaxanthin also showed significant inhibition of tumor formation and growth.

  1. Astaxanthin reduces the risk for Alzheimer’s Disease

Alzheimer’s disease is a progressive disorder that causes brain cells to degenerate and die. Alzheimer’s disease is the most common cause of dementia which is a continuous decline in thinking, behavioral and social skills that disrupts a person’s ability to function independently. There is no known cure for this progressive disease. However, there are several psychotherapies, medications and other treatment options that can help reduce Alzheimer’s disease progression, improve quality of life and reduce the symptoms. Studies have shown that at the onset of the disease presentation, Astaxanthin has significant effects in reducing the risk of progression of the disease and severity of symptoms. This can be linked to the antioxidant properties of Astaxanthin. It also has protective effects against neurodegeneration. It can also trigger recovery for some of the neurological functions in patients who already developed Alzheimer’s. When combined with lifestyle changes, Astaxanthin can be an effective supplement in preventing and decelerating the progression of the disease. Many clinical studies are still ongoing in order to explain further the properties of Astaxanthin that have direct therapeutic effects on the prevention and control of the clinical manifestations of Alzheimer’s disease.

  1. Astaxanthin boosts the Immune System 

Due to its natural antioxidant activity, it ensures the proper functioning of the immune system. It also aids in reducing nerve damage due to chemotherapy and limits allergy manifestations. More than that, its unique molecular structure having a lipophilic and hydrophilic properties permit it to span the entire cell, with one end of the astaxanthin molecule protecting the fat-soluble part of the cell and one end protecting the water-soluble part of the cell. It ensures cells of the body like the Immune cells can function properly. Astaxanthin has been proven to be 6,000 times stronger than vitamin C, 800 times stronger than CoQ10, 550 times stronger than green tea catechins and 75 times stronger than alpha lipoic acid in performing its antioxidant property and thus its function in promoting a good immune system. 

Astaxanthin compared to other antioxidants

With recent developments, effects of Astaxanthin as an antioxidant has been increasingly studied and compared to other known antioxidants. Studies have shown that Astaxanthin has significant superior advantage compared to its counterparts.

  • Astaxanthin vs  Vitamin E – Astaxanthin has superior advantage compared to Vitamin E. It has approximately 550 times better antioxidant property than that of Vitamin E. Both of these antioxidants have a significant role in skin health. However, as noted above, Astaxanthin has been proven to improve texture, appearance, and moisture content of skin while making sure the skin is protected against ultraviolet ray damage. 
  • Astaxanthin vs CoQ10 – Studies show that Astaxanthin has 800 times more activity in fighting against free radicals compared to CoQ10. Both of these antioxidants have cardiovascular health and fertility benefits. 
  • Astaxanthin vs Polyphenols – Polyphenols are mainly found in fruits and vegetables that aid in improving digestion, weight management, and cognitive and cardiovascular health. Astaxanthin is 200 times more potent as an antioxidant than polyphenols. Studies also show that there is significant improvement in cognitive ability in people taking Astaxanthin compared to those who have high intake of polyphenols. 
  • Astaxanthin vs Alpha Lipoic Acid – Alpha lipoic acid is a compound that has a main function on human metabolism. Other than that, it provides protection against cell damage and restore levels of other antioxidants. Studies show that Astaxanthin is 75 more times potent than Alpha lipoic acid. 
  • Astaxanthin vs Anthocyanins – Anthocyanins are flavonoids found mainly in berries and deeply colored plants. It has powerful antioxidant activity that can aid in regulating blood pressure and reducing the risk of infections. Astaxanthin has been found out to have approximately 150 times more activity compared to Anthocyanins. Astaxanthin has been proven to have wider improvement in the immune function compared to anthocyanins. 

Astaxanthin compared to Vitamin C

Vitamin C has long been considered as an essential nutrient that is vital for prevention of scurvy and development of the immune systems. It has been long known as an antioxidant that is commercially available. Researchers have proven that Astaxanthin is 6000 times more effective than Vitamin C in antioxidant activity. Hence, Astaxanthin has higher and more potent activity against reactive oxygen species, making sure that various cognitive and physiological processes can be performed by cells. This finding was lifted in the study of Nishida and Yamashita in 2007. This research claim was also reviewed and confirmed by Zhang et al. in 2016 in which other metabolites as antioxidants were compared according to their activities.

How was the 6000 times more potent activity calculated?

This value was extracted through the measurement of oxygen quenching activity. In order to determine this value, a thermo-dissociable endoperoxide prepared from 1,4-dimethylnaphthalene was used as a singlet oxygen generator. EDN was dissolved with CDCl3 and stored at below 0 degrees Celsius until used. It could release molecular oxygen in the singlet state at 37 degrees Celsius. Chemiluminescence emissions from singlet oxygen were counted with a chemiluminescence detector. 

One hundred eighty microliters of CDCl3 or a mixture of CDCl3:CD3OD (2:1) or DMF containing 0.01 to 50,000 μM of L-Ascorbic acid and Astaxanthin was placed in a thermostated glass tube (12φ X 75 mm) at 37 degrees celsius. Both chemiluminescence counts of a control (S0) without any test compound, and a sample (S) with the identical test compound were recorded. The total quenching constant, generally for total quenching by chemical reaction and/or physical quenching, kT = kq + kr, was analyzed using Stern-Volmer plot equation:

S0/S = 1+ kT・kd -1[Q]. 

where kq is the physical quenching rate constant, kr is the chemical reaction rate constant, kd is the first-order decay rate constant of singlet oxygen in the solvent, and [Q] is concentration of the test compounds. Total quenching constant kT was used to evaluate the activity of L-Ascorbic acid and Astaxanthin.  The result is shown below:

Table 1. Total singlet oxygen quenching rate constants 

astaxanthin-6000-times

Results above show that vitamin C has quenching activity or DMF/CDCl3 (9:1) value of 0.00089 while Astaxanthin has a value of 5.4. If you calculate, the quotient between the two is about 6,067. Proving that Astaxanthin has 6000 times more potent activity as an antioxidant that vitamin c. 

Difference between Astaxanthin and Vitamin C

Vitamin C, also known as ascorbic acid, has long been marketed by the pharmaceutical and beauty industry as one of the most potent antioxidants out there. It has a significant and known ability to stimulate fibroblast cells to produce collagen and gently brighten and smooth skin helping to diminish any unwanted pigmentation. So, they have been used widely in cosmetics. However, its antioxidant activity is not as stable and effective compared to more recently discovered compounds like antioxidants. Thus, it simply can be beaten in this aspect. 

Astaxanthin, as stated above, is a compound that is naturally produced by microalgaes and other microorganisms. It provides pigmentation to different organisms such as shrimp, prawns, and flamingos. They are considered to be under carotenoids in which the most famous member is the Beta Carotene found in carrots, tomatoes, peppers and sweet potatoes. Unlike other antioxidants including Vitamin C and Beta-Carotene, Astaxanthin does not become pro-oxidant in the body nor does it break down into Vitamin A, making it ideal for topical skin care due to its stability. This can be linked to its unique molecular structure having a lipophilic and hydrophilic properties with one end of the astaxanthin molecule protecting the fat-soluble part of the cell and one end protecting the water-soluble part of the cell. Hence, as seen on the figure below, the molecular structure of different antioxidants, Astaxanthin is more stable compared to Vitamin C. 

astaxanthin-compound

Figure 1. Chemical Structure of Different Antioxidants (Lifted from: Nishida et al., 2007)

Other than its significant antioxidant capacity, Astaxanthin has a positive effect on collagen production and sun protection which also varies it from vitamin C. It has been observed that Astaxanthin has photo protective benefits. Recovery is quicker and pigmentation issues reduced. Fibroblasts are skin cells that act as a skin defence system, providing antioxidant enzymes such as Superoxide Dismutase (SOD) and catalase (CAT). When skin is exposed to sunlight, ROS formation and its build-up occurs. Astaxanthin can protect and enhance the ability of the fibroblasts to reduce the formation of ROS and also scavenge ROS after its formation.

Moreover, sunburn is the formation of erythema due to an inflammatory process secondary to prolonged sunlight exposure. Due to potent anti-inflammatory activity of Astaxanthin, it can help protect the skin from developing sunburn or to soothe a sunburn after its formation. Vitamin C does not show this potent sun protection, making Astaxanthin as a superior cosmetic compound. With this plus the benefits of Astaxanthin stated above, it is surely obvious that Astaxanthin has superior activity compared to Vitamin C.

Summary

Indeed, Astaxanthin is currently one of the most studied and talked-about carotenoid compared to its family members such as lycopene, alpha-carotene, and beta-carotene. Astaxanthin is a powerful antioxidant, which is the overarching property behind its several health benefits. Astaxanthin exhibited the most potent singlet oxygen quenching activity compared to different compounds that have been proven to have antioxidant properties. It is reported that the biological activity of astaxanthin originated from potent oxygen quenching and lipid peroxidation suppressing activities. Moreover, Astaxanthin has been proven to be 6,000 times stronger than vitamin C, 800 times stronger than CoQ10, 550 times stronger than green tea catechins and 75 times stronger than alpha lipoic acid in performing its antioxidant property

Oxidative stress is a condition that arises when the balance between free radicals and antioxidants in the body tips towards the former. Too many radicals are responsible for many cases of inflammation in the body. Hence, it is important that antioxidant activity of the body is maintained at high levels. This biological process of oxygen reduction helps keep many health issues and conditions at bay. More than regulating oxidative stress, various benefits of Astaxanthin for human health have been recognized to date: immunomodulation, anti-stress, anti-inflammation, LDL cholesterol oxidation suppression, enhanced skin health, improved semen quality, attenuation of eye fatigue, sports performance and endurance enhancement, limitations on exercised induced muscle damage, limitations of diabetic nephropathy, improvement of hypertension and metabolic syndrome. Astaxanthin obviously plays an important role in promoting quality of life to prevent diseases and maintain a healthy life. 

More conclusive research has yet to be conducted in order to establish firmly and expand more the health benefits and claims regarding Astaxanthin. However, rest assured that astaxanthin is best for your health by virtue of its antioxidant activity and property. In order to reap the full benefits of Astaxanthin, you must intake Astaxanthin 2-4 mg per day together with foods rich in omega-3 such as chia seeds, flaxseed, fish, nutella, walnuts and almonds. With these, you will surely live a more healthy life physically and mentally. 

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