Carotenoids lutein and zeaxanthin linked to better cognitive scores
What it found
In 2796 US adults aged 60 and over, higher intake of the carotenoids lutein and zeaxanthin was linked to better scores on memory, fluency and processing speed tests.
This was a survey, so it cannot show cause and effect.
What they found
Studies in people
Higher intake, better scores
People with higher dietary intake of lutein and zeaxanthin scored higher on each of the three cognitive tests. For example, the highest quartile of intake was linked to a 2.52 point increase on the digit symbol score compared with the lowest quartile.
Supplements showed no link
Lutein and zeaxanthin from supplements alone showed no difference in cognitive scores across quartiles of intake. There was even a small negative association with one memory test, which the authors say could be due to chance or to people taking supplements because of a health diagnosis.
Differences by race
The positive links between lutein and zeaxanthin intake and cognitive scores were generally stronger for Black participants than for white participants. For some tests, the link was significant only in one group.
Other carotenoids
When the authors adjusted for other carotenoids (alpha carotene, beta carotene) and choline, the links with lutein and zeaxanthin did not change much. This suggests the findings were not just due to those other nutrients.
What the authors conclude
“Further research from longitudinal studies is needed, but increasing L and Z intake may help to prevent or slow cognitive decline.”
Also in their conclusions
- They conclude that lutein and zeaxanthin intake were positively associated with multiple measures of cognitive performance in a sample of the U.S. general population of older adults.
- They say that for specific measures, associations were stronger among non-Hispanic Black participants and suggest benefits in multiple domains.
- They advise that further research from longitudinal studies is needed, but increasing lutein and zeaxanthin intake may help to prevent or slow cognitive decline.
How it was done
The authors say antioxidants like carotenoids may limit damage to neurons from free radicals, and that low intake of dietary antioxidants may be a modifiable risk factor for cognitive decline. They wanted an up-to-date population-based study of this link in older adults.
They used data from the National Health and Nutrition Examination Survey (NHANES) 2011-2014, a cross-sectional survey of the US population. They looked at 2796 participants aged 60 years and older who had completed cognitive tests and had dietary lutein and zeaxanthin intake estimated from two 24-hour diet recalls.
What it can’t tell you
- This was a cross-sectional survey, so it can show a link but cannot prove that lutein and zeaxanthin cause better cognitive scores.
- The dietary data came from 24-hour recalls, which may not reflect usual intake over time.
- The results may not apply to all older adults because some groups were more likely to be included in the analysis.
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 26 Sep 2026. Check it against the paper before it changes what you eat. How we summarise papers · Report an error