Astaxanthin

Studies in people

• Open question

  Inflammation after hard exercise²

  In firefighters, astaxanthin seemed to calm some inflammation after hard workouts, but most differences were within groups.

• Benefit

  PCOS symptoms and inflammation³

  In women with PCOS, astaxanthin lowered some inflammation markers, but did not improve weight, hair growth, hair loss or periods.

• Benefit

  Heart failure symptoms⁴

  In people with heart failure, astaxanthin supplements improved breathlessness and tiredness over eight weeks, but studies are still limited.

• Benefit

  Eye-hand coordination⁵

  In people, a supplement with astaxanthin, lutein and zeaxanthin helped eye-hand coordination after screen work.

• Benefit

  Sun-damaged skin⁶

  People taking astaxanthin for 9 weeks showed less sun-related skin moisture loss and better rough skin scores.

• Open question

  Oxidative stress in overweight adults⁷

  In overweight adults, astaxanthin supplements for 3 weeks changed blood markers of oxidative stress.

• Open question

  Fat breakdown in the body⁹

  In healthy men, three months of astaxanthin capsules may have reduced the breakdown of fats.

• Open question

  Egg quality in IVF¹⁰

  In women with PCOS, astaxanthin led to more mature eggs, but scientists do not yet know whether it lowers OHSS risk.

• Benefit

  Blood sugar and cholesterol¹¹

  In obese men, astaxanthin plus CrossFit improved insulin, glucose and lipid levels over 12 weeks.

Animal and lab studies only

• Benefit

  Heart and eye health¹⁶

  Astaxanthin is said to help prevent heart disease and cataracts, but most research so far is in lab studies.

• Benefit

  Gum and jawbone health in diabetes¹⁷

  In diabetic mice, astaxanthin reduced gum and jawbone damage, but did not lower blood sugar.

• Open question

  Exercise recovery evidence¹⁸

  In animal and lab studies astaxanthin improved exercise recovery, but studies in people have given mixed results.

• Benefit

  Fatty liver after menopause²⁰

  In mice without ovaries, astaxanthin lessened liver fat, inflammation and scarring.

• Open question

  Clogged arteries²²

  In lab studies, astaxanthin stopped foam cells forming and calmed inflammation, but the authors did not say if it helps people.

Study type not stated

• Open question

  Long-term eating effects¹²

  Natural astaxanthin cut oxidative and free-radical stress more than synthetic astaxanthin, but long-term eating risks are not well studied.

• Open question

  Long-term health effects¹³

  Scientists do not yet know whether eating synthetic astaxanthin over many years affects human health.

• Benefit

  Antioxidant health effects¹⁴

  Astaxanthin from microalgae is used as a colour in food and feed, and may have health benefits.

• Open question

  Heart and blood vessels¹⁵

  Astaxanthin may help prevent hardened arteries, but scientists do not yet know whether it truly works in people.

How it’s made and used

• Exercise performance in cyclists⁸

  In trained cyclists, taking astaxanthin for four weeks did not improve fat burning or time trial performance.

• Gut bacteria and tryptophan¹⁹

  In lab studies, astaxanthin changed gut bacteria and raised the breakdown products of tryptophan.

• How much the body absorbs²¹

  In lab studies, cooking wild salmon lowered astaxanthin bioaccessibility, and uncooked wild salmon gave more than uncooked farmed salmon.

The signal at the top counts the findings in people and in animal and lab studies. A concern in studies of people outranks animal and lab studies, and “No concerns” needs at least one finding in people. When most findings in people point one way, the page leans that way (“Mostly”), and every finding is still shown. Findings whose study type is not stated are shown but not counted. This page is a reference, not medical advice. It describes what regulators and published research say. Talk to a doctor or dietitian about your own diet.