A Complete Guide to Astaxanthin: Benefits, Side Effects, & Contraindications

Published on July 08, 2024

By Kristen Boye BS, Natural Health

Kristen Boye

Kristen Boye is a natural health expert, writer, copywriter, and editor. Kristen was raised on an organic farm in British Columbia which inspired her life’s work. She holds a Bachelor’s Degree in Natural Health, is a Certified Natural Foods Chef, co-owner of a medicinal herb farm, and is a natural foods and children’s health advocate. Kristen lives with her husband and two children on their medicinal herb farm in Western North Carolina.

If you’ve browsed the antioxidant, skincare, or joint and mobility section of your local supplement retailer, you’ve probably come across Astaxanthin.

If its name is unfamiliar, that’s because it’s not your typical herb or nutritional supplement.

So, what is this strange-sounding supplement and how can it benefit health?

In this article we’ll explain everything you need to know about Astaxanthin, including what it is, its benefits, side effects, and contraindications.

What is Astaxanthin?

Astaxanthin, also known as AST, is not an herb, plant, vitamin, or mineral. Rather it is a natural C40 carotenoid pigment found in salmon, shrimp, trout, microalgae, and yeast. 

Astaxanthin is most commonly found in Pacific salmon and is what gives these fish their signature pinkish-red color.

Numerous studies have shown Astaxanthin has powerful antioxidant properties* that may positively impact various facets of health related to inflammatory response, skin, joint function, and more.

*Antioxidants are molecules found within the body and in nature that delay cell damage by scavenging unstable molecules known as free radicals.REF#4165

How is Astaxanthin Extracted? Is There a Vegan Option?

AST is extracted from microorganisms; phytoplankton; bacteria; yeast; and marine animals, such as shrimps, lobster, asteroidean, algae, crustaceans, trout, krill, red sea bream and salmon.REF#4166

However, most high-quality Astaxanthin supplements on the market come from Haematococcus pluvialis, a type of green microalgae, REF#4167 and are therefore vegan (assuming they’re encased in a non-gelatin capsule).

Fish oil also contains small amounts of Astaxanthin, with Krill Oil being the richest source.

Non-vegans can also get Astaxanthin naturally by eating salmon, shrimp, trout, and other redfish and seafood.

7 Benefits of Astaxanthin

As you’ve just learned, Astaxanthin’s antioxidant properties have been studied for various actions on human health.

Here, we examine the emerging research behind seven potential benefits of Astaxanthin for inflammatory response, cognitive function, joint health, exercise performance, and more.

1: Astaxanthin is Rich in Powerful Antioxidants

As discussed previously, the primary benefits of Astaxanthin are attributed to its carotenoid pigments, which act as powerful antioxidants.

Antioxidants, like Astaxanthin, provide broad-spectrum health benefits through their cell-protective and inflammatory response-supportive properties.

Astaxanthin’s antioxidant profile stands out from other antioxidants because it’s been shown to have the highest oxygen radical absorbance capacity (ORAC), 100-500 times higher than ⍺-tocopherol (a form of Vitamin E) and a ten times higher free radical inhibitory activity than related antioxidants such as α-tocopherol, α-carotene (alpha-carotene), β -carotene (beta carotene), lutein, and lycopene.REF#4168

We’ll discuss more about how Astaxanthin promotes health in subsequent sections.

2: Astaxanthin May Support Normal Inflammatory Response

Thanks to new research, we also now know that the inflammatory response is directly connected to vital organs and systems such as the heart, cardiovascular system, reproductive system, musculoskeletal system, immune system, and more.

This is why so many progressive doctors and integrative health practitioners are recommending diet and lifestyle changes that support a normal inflammatory response.

One of the best allies for the inflammatory response system is antioxidant compounds. These compounds help regulate the inflammatory response by reducing the negative impacts of free radical damage on cells, known as oxidative stress.

Specifically, Astaxanthin has been shown to help prevent oxidative stress in cells, thereby supporting mitochondrial regulation and function (the mitochondria are the energy-producing layers of the cell) and normal inflammatory response of the skin, kidneys, gastrointestinal system, eyes, brain, immune and musculoskeletal systems.REF#4169 REF#4170 REF#4171

Although more research is needed, several studies suggest Astaxanthin may be instrumental in supporting normal function of the body’s inflammatory response.

3: Astaxanthin May Benefit the Eyes

Sight is one of our most precious senses, literally shaping how we see and experience the world around us.

Yet people of all ages struggle with various vision issues, especially in the digital age, where screen-related vision issues are on the rise.REF#4172

Studies suggest Astaxanthin may support healthy vision via its antioxidant effects on inflammatory response, its potential to support normal blood flow to various parts of the eye, and its positive impacts on focus.REF#4173 REF#4174

Although more robust studies are needed, the premise of antioxidants supporting eye health is nothing new. 

In World War II, for example, reports of improved night vision in fighter pilots were credited to regular intake of Bilberry jam, a berry that is rich in antioxidants.REF#4175

4: Astaxanthin May Promote Youthful Skin

Antioxidants have long been used to promote youthfulness and help reduce signs of aging.

Several studies report skin benefits from taking astaxanthin, including:REF#4176

  • A reduction in signs of sun damage
  • Softening of wrinkles
  • Improved skin elasticity
  • Improved hydration
  • Reduction of redness

Astaxanthin is also found in various topical skin care products such as creams, serums, and lotions.

Related read: 10 Herbal Beauty Tips for Plant-Based Skin, Hair, & Beauty Care.

5: Astaxanthin May Support Cognitive Function

New research has shown a direct link between cognitive and brain function and oxidative stress.REF#4177

This is why antioxidants like Astaxanthin and those found in other plants and functional foods, have become the subject of various studies related to cognitive health.

Specifically, studies suggest Astaxanthin, which as a lipid-soluble pigment crosses the blood-brain-barrier, may support various aspects of cognitive function including:REF#4178 REF#4179

  • Nerve cell regeneration
  • Normal genetic expression related to essential proteins for brain recovery, such as glial fibrillary acidic protein (GFAP), microtubule-associated protein 2 (MAP-2), and brain-derived neurotrophic factor (BDNF).
  • Memory
  • Response time

It may also act as a neuroprotective, REF#4180 but more research is needed.

6: Astaxanthin May Support Heart & Cardiovascular Function

Antioxidant-rich foods like colorful fruits and vegetables are generally highly recommended as part of a heart-healthy diet.

That’s because their various antioxidants have been shown to provide numerous potential benefits to cardiovascular function through their cell-protective and inflammatory support properties.

Emerging research suggests Astaxanthin may be helpful in supporting normal cholesterol and possibly arterial function, but more research is needed.REF#4181 REF#4182 REF#4183

Additional research suggests Astaxanthin may also help support normal glucose metabolism, which may provide direct or indirect benefits to the cardiovascular system.REF#4184

More research is needed to understand how Astaxanthin may impact the cardiovascular and metabolic systems.

7: Astaxanthin May Support Immune Function

Earlier, we mentioned the connection between the immune system and inflammatory response. Here’s how that works.

When the immune system is activated, it turns on the body’s inflammatory response by producing inflammatory cells, such as cytokines, to help fight pathogens.REF#4185

Normal production of proinflammatory cells, like cytokines, is essential for human survival. However, over-production can lead to problems.

A few small studies suggest Astaxanthin may help regulate the immune response through its effects on promoting normal inflammatory response, but more research is needed.REF#4186 REF#4187

Astaxanthin Contraindications & Side Effects

Astaxanthin is Generally Recognized As Safe (GRAS) by the FDA in doses up to 6 to 7 mg daily, from Haematococcus pluvialis (H. pluvialis) a green microalgae, or Paracoccus carotinifaciens (P. carotinifaciens a type of bacterium.

As previously discussed, most Astaxanthin used in supplements come from Haematococcus pluvialis (H. pluvialis).

Recommended or approved doses in different countries range between 2 and 24 mg daily, REF#4188 which suggest safety ranges regarding dosing are broad.

Side effects are rare and typically include mild stomach or digestive upset. Even with very high doses the worst side effects recorded were diarrhea or very frequent bowel movement and red-colored stool.

Note: If you have a fish or shellfish allergy, always check with your doctor and ensure the supplement is made in an allergen-free facility. Some people with these allergies can consume algae, while others cannot.

Interested In Learning More About Plant-Based and Herbal Antioxidants?

Antioxidants are truly nature’s gift to help support nearly every aspect of health in an often unnatural world.

Plant-based antioxidants like Quercetin, Curcumin, Resveratrol, Beta Glucans, and others are often considered the active components in traditional herbs, responsible for their many health benefits.

To learn more about beneficial antioxidants in herbs, check out the following articles:


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