Canthaxanthin in trout feed and residues in fillets
What it found
Rainbow trout fed canthaxanthin and astaxanthin for 56 days built up residues in their muscle.
The amounts people would get from eating the fillets were too low to reach the beneficial effects other authors have described.
What they found
Animal and lab studies
Residues in trout muscle
After 56 days of feeding, trout muscle contained 3.70 mg/kg of astaxanthin and 1.21 mg/kg of canthaxanthin.
Studies in people and animals
Weekly intake from fish
Based on average fish consumption, the highest levels found in trout fillets would give people weekly intakes of 1.63 mg of astaxanthin and 0.53 mg of canthaxanthin.
Too low for benefits
Those weekly amounts are not enough to achieve the positive effects described by many authors.
Still a carotenoid source
Even so, the residues could be an important source of carotenoids, as an alternative to synthetic dietary supplements.
What the authors conclude
“these values are not sufficient to achieve the positive effects described by many authors, but their residues could still represent an important source of carotenoids, alternative to the use of synthetic dietary supplements.”
Also in their conclusions
- They say the weekly intakes from trout fillets are not sufficient to achieve the positive effects described by many authors.
- They note that the residues could still represent an important source of carotenoids, alternative to the use of synthetic dietary supplements.
How it was done
Xanthophylls like astaxanthin are thought to have benefits for human health, so their use in food supplements is encouraged. They are also widely used in fish farming to give salmon-like flesh its colour.
Rainbow trout were given different feeding plans with xanthophyll additives over 56 days. Muscle samples were then tested for leftover astaxanthin and canthaxanthin.
What it can’t tell you
- We summarised it from the abstract only.
- This was a study in trout, so it cannot show what happens in people who eat the fish.
- The weekly intake figures are estimates based on average fish consumption, not measured intakes in people.
The paper
- Title
- Astaxanthin and canthaxanthin (xanthophyll) as supplements in rainbow trout diet: in vivo assessment of residual levels and contributions to human health
- Type
- Study
- Evidence
- Studies in people · animals · lab
- Summarised from
- Abstract only
- Cite
- Brizio P, Benedetto A, Righetti M, et al (2013). Astaxanthin and canthaxanthin (xanthophyll) as supplements in rainbow trout diet: in vivo assessment of residual levels and contributions to human health. Journal of agricultural and food chemistry. doi:10.1021/jf4012664PubMed 24156372DOI
Summary written 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error