Carotenoids lutein and zeaxanthin linked to better thinking in older adults
What it found
Higher intake of the carotenoids lutein and zeaxanthin was linked to better scores on memory and thinking tests in 2796 US adults aged 60 and older.
The link was generally stronger for Black participants than for white participants.
What they found
Studies in people
Better test scores overall
People who ate the most lutein and zeaxanthin scored higher on all three thinking tests. For example, those in the top quarter of intake scored 2.52 points higher on a symbol matching test than those in the bottom quarter.
Differences by race
The positive link between these carotenoids and test scores was generally stronger for Black participants compared with white participants. Both groups showed benefits, but the patterns varied depending on which test was used.
Food versus supplements
Lutein and zeaxanthin from food were tied to better thinking scores. However, taking these carotenoids as supplements alone showed a small negative link with one memory test, possibly because people already having health issues were advised to take them.
Typical daily intake
The middle value for total lutein and zeaxanthin intake across food and supplements was 1046 μg per day. This matches earlier reports of 1 to 2 mg per day in the American population.
What the authors conclude
- They found that eating more lutein and zeaxanthin was tied to better performance on several thinking and memory tests in older US adults.
- They suggest that targeting people at risk of cognitive decline with dietary changes could be more effective than broad public advice that often goes ignored.
- They call for long-term studies to confirm whether increasing intake of these carotenoids can actually prevent or slow mental decline.
How it was done
Free radicals can damage brain cells as people age, and antioxidants like carotenoids might limit that harm. The authors wanted to see if eating more lutein and zeaxanthin was tied to sharper thinking in older adults.
They looked at survey data from 2796 US adults aged 60 and older collected between 2011 and 2014. Participants recalled everything they ate over two 24-hour periods so researchers could estimate their lutein and zeaxanthin intake. Trained interviewers then gave them three tests measuring memory, word fluency, and processing speed.
What it can’t tell you
- Because this was a snapshot in time, it cannot show that eating more lutein and zeaxanthin causes better thinking skills. People who eat more of these nutrients might simply have healthier lifestyles overall. Two days of diet recall may not reflect what someone usually eats over the years needed for these nutrients to build up in the brain.
Who paid
- Funding
- Funded by NIA NIH HHS (from the PubMed record).
- Authors work at
- University of Wisconsin, USA; University of Wisconsin School of Medicine and Public Health, USA; William S. Middleton Memorial Veterans Hospital, USA
The paper
- Title
- Dietary carotenoids and cognitive function among US adults, NHANES 2011-2014
- Type
- Study
- Evidence
- Studies in people
- Summarised from
- Full text
- Cite
- Christensen K, Gleason CE, Mares JA (2020). Dietary carotenoids and cognitive function among US adults, NHANES 2011-2014. Nutritional neuroscience. doi:10.1080/1028415X.2018.1533199Free full textPubMed 30326796DOI
Summary written 30 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error