The Study
The effects of supplementation with lutein and/or zeaxanthin on human macular pigment density and colour vision
This study watched what happened to 24 people’s eyes after they took special vitamins, and noticed that their yellow-blue vision didn’t change, but their red-green vision might have gotten a tiny bit better. But because we don’t know if they were randomly assigned or if the researchers knew who got the vitamins, we can’t say the vitamins caused the change.
Analysis score
Maximum 90 for a randomized controlled trial.
Where the score came from
Scientists gave people yellow supplements to see if it helped them tell colors apart, especially blue-yellow and red-green.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 520 / 100
Quality score
Participants are randomly assigned to treatment or control groups, minimizing bias. The gold standard for testing whether an intervention causes an effect.
Key takeaways
Summary
Based on the study abstract and findings.
- 1The improvement in red-green vision is so small it likely doesn't matter in daily life; blue-yellow vision is unchanged.
- 2The supplements made the yellow pigment in the center of the eye thicker, but people still couldn't tell blue and yellow apart any better.
- 3They got slightly better at telling red and green apart, but only a tiny bit.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Ophthalmic and Physiological Optics
Year
2006
Authors
M. Rodriguez‐Carmona, J. Kvansakul, J. Alister Harlow, W. Köpcke, W. Schalch, J. Barbur
Related Content
Claims (6)
Lutein and zeaxanthin build up in the central part of the retina and absorb blue light, which reduces damage to light-sensitive cells.
Taking lutein and zeaxanthin supplements increases the density of macular pigment in the central part of the retina in healthy adults, no matter how much pigment they had before.
In healthy adults, the ability to distinguish red and green colors remains within normal limits regardless of lutein or zeaxanthin supplementation, but higher levels of macular pigment are weakly linked to slight changes in color discrimination.
Taking lutein and zeaxanthin supplements increases the density of pigment in the central part of the retina in healthy adults with normal color vision, but this increase does not improve their ability to distinguish yellow and blue colors.
In healthy adults with high levels of macular pigment, taking lutein and zeaxanthin supplements is linked to a small increase in the ability to distinguish between red and green colors.
The amount of yellow pigment in the center of the eye does not change how well healthy adults distinguish between yellow and blue colors, even when they take supplements that increase this pigment.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.