Astaxanthin from microalgae: health effects and food use
What it found
Most studies of astaxanthin's health effects have been done in cells or animals, not people.
The authors say more human studies are needed.
What they found
Animal and lab studies
Brain enzymes in mice
In mice, astaxanthin consumption at 2 mg per kg per day led to higher levels of antioxidant enzymes such as catalase and superoxide dismutase in the brain. It also boosted the brain's glutathione level.
Inflammation and gut
In mice, astaxanthin decreased gastric inflammation caused by bacterial infections and affected intestinal bacteria, reducing inflammation and oxidative stress. It also reduced bacterial load and gastric inflammation in mice infected with Helicobacter pylori.
Immune system in mice
In mice with a weakened immune system, astaxanthin at 60 and 120 mg per kg of body weight prevented damage to the intestinal lining. The authors note these doses are much higher than the acceptable daily intake of 0.2 mg per kg of body weight set by EFSA in 2020.
Antiviral effect in cells
In monkey kidney cells, an extract of H. pluvialis rich in astaxanthin at 75 mg per litre stopped herpes simplex virus type-1 infection by 85% and affected its replication inside cells.
Other findings
Antioxidant strength
Astaxanthin has the highest antioxidant capacity reported for a natural compound, higher than other carotenoids. It is 100 times more antioxidant than vitamin E in neutralizing singlet oxygen.
Food and feed uses
Astaxanthin is used as a red pigment in food, feed and aquafeed, and in cosmetics. In food products like lamb patties and chicken steaks, it reduced lipid oxidation during storage and improved colour stability and consumer acceptance.
What the authors conclude
“Further in vivo human studies are needed to fully understand the potential of this valuable compound.”
Also in their conclusions
- They conclude that natural astaxanthin has several health-promoting properties, mostly due to its very high antioxidant capacity.
- They state that most studies so far were done in vitro and in animal models, and that further human studies are needed to fully understand the potential of this compound.
- They note that the results so far are promising and suggest a bright future for producers of microalgal astaxanthin.
How it was done
Consumers want foods that are tasty, nutritious and sustainable, and microalgae are rich in useful compounds. The authors wanted to review the challenges and opportunities of using microalgae-derived astaxanthin as a food ingredient.
They reviewed published research on astaxanthin, including a search of the Scopus database that found 5715 documents published from 1947 to 2021. They also looked at studies on its health effects, food and feed uses, and production.
What it can’t tell you
- Most of the health studies were done in cells or animals, so they cannot show what happens in people.
- Human studies so far have had a limited number of participants, so they cannot provide strong evidence for health claims.
- The review cannot show whether astaxanthin prevents or treats any disease in people.
Who paid
- Funding
- Funded by Ministerio de Ciencia, Innovación y Universidades; University of Almería; FEDER; Fundación BBVA (from the PubMed record).
- Conflicts
- The authors declare no conflict of interest.
- Authors work at
- University of Almería, Spain; Joint Centre University of Almería-CIEMAT, Spain
The paper
- Title
- Microalgae Derived Astaxanthin: Research and Consumer Trends and Industrial Use as Food
- Type
- ReviewThe authors read earlier studies and describe what they found. It isn’t a new study.
- Evidence
- Animals and lab studies
- Summarised from
- Full text
- Cite
- Villaró S, Ciardi M, Morillas-España A, Sánchez-Zurano A, Acién-Fernández G, Lafarga T (2021). Microalgae Derived Astaxanthin: Research and Consumer Trends and Industrial Use as Food. Foods (Basel, Switzerland). doi:10.3390/foods10102303Free full textPubMed 34681351DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error