Life Extension Magazine®

Woman putting sunscreen on to prevent skin cancer

Astaxanthin Provides Broad Spectrum Protection

Over the past decade, researchers have recognized that astaxanthin’s unique molecular structure traps more free radicals compared to most other nutrients.  Its full benefits, however, have been limited due to its relatively poor absorption ability.  By combining carotenoids like astaxanthin with phospholipids, their bio-availability increases by nearly 12-fold for more potent systemic protection.

Scientifically reviewed by: Dr. Carol Campi, RN, DC, in August 2023. Written by: Liam Hawkins.

 
Happy young woman under blue sky, portrait

Researchers in Japan have long looked to the sea for sources of new medications. A big focus has been on astaxanthin found in microalgae.1,2

Astaxanthin functions as a natural sunscreen for marine plants.3 Because astaxanthin is so effective at absorbing solar radiation, investigators first proposed it would make an effective topical sunscreen.1-4 But as researchers looked closer, they discovered that astaxanthin shields other areas against destructive free radicals.4,5 

Almost every cell in the body, including the eyes, brain, heart, and kidney, can benefit from astaxanthin.1,6,7 Recent laboratory studies show that astaxanthin can even increase life span!8,9

The discovery of a new way to  boost astaxanthin absorption by 12-fold means more of this broad-spectrum nutrient is available to your entire body.

Astaxanthin is a red pigment molecule that is a member of the carotenoid family found in certain marine algae. When eaten by shrimp and crustaceans, the pigment lends its reddish hue to their shells. As astaxanthin makes its way up the food chain, the color becomes still more concentrated, creating the beautiful reds and pinks we see in fish such as salmon and in marine birds like flamingos.6

Researchers have sought to explore the use of astaxanthin as a topical sunscreen because of its powerful ultraviolet light-absorbing properties.5 They soon found, however, that astaxanthin has many additional benefits, including free radical scavenging, mitochondrial protection, anti-inflammatory effects, and protection from glycation.11-18

In the words of one researcher, astaxanthin shows “demonstrable promise for slowing age-related functional decline.”19

Though the work is only in its infancy, astaxanthin has already been shown to extend the life span of the simple worm called C. elegans.8,9 Extending life in primitive organisms like C. elegans is an important first test of compounds with the potential for increasing longevity in humans.

Let’s examine some of the more compelling literature on astaxanthin, highlighting its vast ability to protect and promote healthy immune functioning, reduce cancer risk, mitigate the impact of diabesity, protect heart muscle and blood vessels, slow brain aging, and support eye health.

Astaxanthin: Potent Skin Protection from the Inside Out

tanning

Recent studies show that astaxanthin can rejuvenative skin from within.4,11,20 Astaxanthin is among the most powerful and versatile marine plant antioxidants known, and as such, it has the ability to scavenge skin-damaging free radicals.4,19,21 Even though astaxanthin is widely distributed through most organs in the body, it accumulates in the skin, where it makes its way into all skin layers (topical sunscreens can reach only the outermost layers).22,23 This can provide potent protection against ultraviolet radiation, the most powerful environmental risk factor for skin cancer.4

Skin cells that are exposed to ultraviolet light produce bursts of free radicals that trigger aging effects such as skin sagging, wrinkles, and possible cancerous changes.4,24 When astaxanthin is applied to skin cells in culture, it prevents all of those ultraviolet-induced destructive effects, suggesting that it should significantly prevent ultraviolet-induced skin aging.4,24,25

Human studies demonstrate that 6 mg/day of oral astaxanthin for 6-8 weeks reduces crow’s feet wrinkles, water loss, and age spot size while enhancing moisture content, elasticity, and skin texture in both men and women, particularly when combined with topical astaxanthin application.23

Boosting Immune Function

Your immune system protects you from infections and routinely patrols your body for emerging cancer cells, but when it is over-activated, it can trigger allergic responses such as asthma and autoimmune diseases. Studies demonstrate that astaxanthin helps balance the immune system by stimulating its infection- and cancer-fighting components—while also helping suppress the overactive immune responses that create needless inflammation.26

Astaxanthin increases the numbers and activity of white blood cells called lymphocytes and natural killer cells that are responsible for creating the body’s innate immune response to invaders.27-29 In a mouse model of breast cancer, animals treated with astaxanthin prior to tumor initiation showed higher levels of cancer-killing cells and protective interferon resulting in delayed tumor growth.27

Astaxanthin has similar immune-boosting effects in humans, improving the ability of protective white blood cells to surround and destroy infecting organisms, especially fungi such as Candida albicans.30 Astaxanthin also protects human lymphocytes and neutrophils against the oxidant stresses imposed by the actions of certain white blood cells without reducing the killing effects of white blood cells themselves.30,31

Human studies reveal astaxanthin’s beneficial actions on the over-activated immune system in patients with allergies and asthma. When astaxanthin (along with ginkgo extract) was applied to white blood cells from asthmatic patients, it suppressed reactive cell activation as well as or better than the antihistamine drugs cetirizine (Zyrtec®) and azelastin (Astelin®).32 A subsequent study showed that combining these compounds with the drugs resulted in improved antihistamine activity.33

Preventing Cancer at Every Stage

Epidemiological studies reveal that dietary intake of astaxanthin along with other carotenoids is associated with the reduced risk of many different types of cancer. Increased intake of carotenoids such as astaxanthin typically lowers cancer risk.34

Unlike many pharmaceuticals, astaxanthin shows beneficial effects against cancer at each stage of its development.

  1. It prevents cancer initiation by protecting DNA from ultraviolet and oxidant damage.4,35
  2. It promotes early detection and destruction of cells that have undergone malignant transformation by boosting immune surveillance.7
  3. It prevents cancerous growth in cells that evade immune detection by reducing inflammatory changes such as those that appear in aging.12,36
  4. It blocks the rapid cell replication of tumors in their growth phase by stopping the cancer cell reproductive cycle and restoring cancer cells’ ability to die off by apoptosis.37-40
  5. It prevents tumors from spreading by reducing tumor production of tissue-melting proteins.36

Animal studies show that these properties of astaxanthin contribute to a reduced number of precancerous lesions in the colon, and to fewer and smaller tumors when they do develop in the colon and breast.27,41

What You Need to Know
colorful yellow red seaweed algae on sea ocean shore coastline

Diverse Health Benefits of Astaxanthin

  • Japanese scientists developed astaxanthin from marine algae as a potent oral agent to protect against ultraviolet damage to skin.
  • Other appealing properties of astaxanthin have since emerged, supporting its role as an antiaging supplement that protects organs throughout the body from the ravages of oxidant stress, inflammation, glycation, and mitochondrial dysfunction.
  • Astaxanthin promotes healthy immunity and suppresses inflammation, especially in allergies and asthma, while protecting tissues from the impact of obesity and diabetes, shielding blood vessel cells from damage, preventing changes that lead to cancer, slowing cognitive decline, and preserving vital eye functions.

Reducing Diabesity and Its Consequences

Diabetes and obesity are so closely intertwined that scientists now speak of them together as one entity, diabesity. Diabesity is a major component of metabolic syndrome. Astaxanthin holds multiple benefits in managing diabesity and its resulting oxidant stress, high levels of chronic inflammation and extensive tissue damage from protein and lipid glycation.42

Lab studies reveal that when obese and/or diabetic animals are supplemented with astaxanthin, they experience lower blood glucose levels, improved insulin sensitivity, and reduced inflammation and oxidative stress.42-45 In addition, astaxanthin preserved the ability of the pancreas to secrete insulin.42

Astaxanthin supplementation also prevents massive body weight gain in animals fed high-fat or high-fructose diets.45,46 Obese animals, like obese humans, develop dangerous fat accumulations in their livers, predisposing them to cirrhosis and liver cancer. Astaxanthin supplements have been found to reduce liver fats and triglyceride levels.46 In overweight and obese humans, astaxanthin suppresses dangerous lipid peroxidation and stimulates healthy natural antioxidant defenses in the body.47

In addition to preventing the main elements of diabesity, astaxanthin helps alleviate the long-term consequences faced by diabetics. Studies show that astaxanthin supplementation slows the development of diabetic nephropathy (kidney disease),43,48 reduces cataract formation and diabetic retinopathy (both preventable forms of blindness in diabetics),49,50 and reduces the many cardiovascular complications of diabesity.51

How to Enhance the Bioavailability of Astaxanthin
body,lipid,treatment,blood

Much as we shun them in our diets, fat molecules are essential to human life and function. But the fats that form our cell membranes are a special kind of molecule called phospholipids. Phospholipid molecules have electrically charged “heads” that mix well with water on the inside and outside of cell membranes and neutral “tails” that mix with fats within the cell membrane.

These properties make phospholipids ideal as “emulsifiers,” agents that help oil molecules mix with water. Carotenoids like astaxanthin are mostly oil-soluble and, therefore, mix poorly with water, limiting their bioavailability. By emulsifying such molecules with phospholipids their absorption is enhanced nearly 12-fold compared to carotenoids formulated without phospholipid74

Emulsification of fat-soluble molecules like astaxanthin is just one of the unique properties of phospholipids. These versatile molecules give cell membranes, particularly those of brain and nerve cells, their special characteristics which include the ability to modulate inflammation.75,76 A molecule called phosphatidylcholine is the most abundant phospholipid in such cells.77

Our bodies can make some phosphatidylcholine but still require outside sources (such as choline) to maintain supplies. Phospholipids, like all fats, are extremely prone to oxidation (that’s why butter and oil go rancid). Studies show that astaxanthin incorporates itself perfectly into and across the fat-laden cell membrane, where it acts as a powerful inhibitor of lipid oxidation.78-80

You need phosphatidylcholine to protect nerve cell function, and you need astaxanthin to protect phosphatidylcholine from destructive oxidation. As an added bonus, phosphatidylcholine helps with intestinal absorption of supplemental carotenoids.

To ensure optimal assimilation, take astaxanthin supplements with the meal that contains the most fat.

Protecting Cardiovascular Health

Astaxanthin has powerful antioxidant effects that fight cardiovascular diseases at multiple levels. In hypertensive rats, astaxanthin lowers blood pressure, improves endothelial function, and delays hyper-tension-induced strokes.52-54 In humans and animals, astaxanthin helps normalize lipid profiles, reducing triglyceride and cholesterol levels while boosting beneficial HDL-cholesterol.55,56 These effects may reduce the risk of a clot forming within a major vessel.

Astaxanthin also reduces inflammation and the production of certain enzymes that destabilize plaques making them more vulnerable to rupture and to blocking blood flow.57

In the heart muscle itself, astaxanthin boosts mitochondrial energy delivery, which helps the heart muscle contract more powerfully and efficiently.58 This is especially valuable in the event of a heart attack because it helps surviving muscle to rapidly take over from damaged areas.

People with cardiovascular disease are at risk for vascular dementia, a form of cognitive decline caused by decreased brain blood flow and damage to cerebral vessels. Astaxanthin supplements in such animals reduce the rate of complications such as strokes and improve cognitive performance allowing the animals to live more vigorous and active lives.52

Slowing Brain Aging

Cat screens on screens

Astaxanthin exerts multiple beneficial effects in the brain.59 Unlike many other antioxidant molecules, astaxanthin crosses the blood-brain barrier, allowing it to saturate and protect brain tissue.14 These features have led experts to label astaxanthin a “natural brain food.”14

In animal models, astaxanthin has been found to reduce the risk of stroke, diminish the size of stroke areas in the brain, and improve motor activity following a stroke.60-62 One study, in fact, demonstrated that pre-treatment with astaxanthin completely prevented ischemic brain injury following 2 hours of blockage of one of the brain’s largest arteries.62

Astaxanthin also directly combats the oxidative impact of abnormal proteins in both Alzheimer’s and Parkinson’s diseases.59,63,64 Studies show that beta-amyloid, the toxic protein found in the brains of Alzheimer’s patients, is also found on red blood cells, where it reduces oxygen delivery to tissues.65 Supplementation with astaxanthin has been found to decrease the accumulation of amyloid-beta on red blood cells.66

A human study has determined that doses of astaxanthin as high as 20 mg once daily for 4 weeks are free of side effects and suggested that the supplement was effective for age-related decline in cognitive and psychomotor functions.67 And 12 mg/day astaxanthin improved cognitive health scores and learning scores in a study of healthy middle-aged and elderly subjects with age-related forgetfulness.68

Important Promoter of Eye Health

Age- and diabetes-related eye diseases contribute to visual impairments and blindness in millions of Americans. Astaxanthin has been found to prevent or slow three of the most common eye diseases: age-related macular degeneration, cataracts, and glaucoma. 

The human retina naturally contains the carotenoids lutein and zeaxanthin, molecules closely related to astaxanthin. Supplementation with all three carotenoids (astaxanthin 4 mg/day, lutein 10 mg/day, zeaxanthin 1 mg/day) has been shown to improve visual acuity and contrast detection in people with early age-related macular degeneration.69 In laboratory studies, astaxanthin supplementation protects retinal cells against oxidative stress and significantly reduces the area of destructive new blood vessel growth on retinas, a hallmark of advanced macular degeneration.70,71

Studies of patients with age-related macular degeneration reveal significant improvements in retinal electrical outputs following supplementation with astaxanthin and other carotenoids.72

Glaucoma, an increase in the pressure of fluid inside the eyeball, eventually results in retinal cell death from oxidant damage and loss of blood flow. In a rodent study, astaxanthin restored retinal parameters to normal in eyes with experimentally-induced glaucoma.73

Summary

Astaxanthin, a red pigment that originates in marine algae, is one of nature’s most potent antioxidants. It has numerous other useful properties as well: it is an efficient blocker of ultraviolet radiation, it reduces the impact of glycation, and it decreases inflammatory responses.

Studies are revealing astaxanthin’s remarkable ability to fight the prime causes of aging, not only in the skin, where it was first studied, but in organs and tissues throughout the body. Astaxanthin protects and promotes healthy immune functioning, reduces cancer risks, mitigates the impact of diabesity, protects heart muscle and blood vessels, slows brain aging, and supports eye health.

These multiple benefits of astaxanthin, coupled with its proven safety record, make it a vital component of a responsible program of nutritional supplementation.

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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