Higher antioxidant levels may lower risk for dementia

People with higher levels of antioxidants in their blood may be less likely to develop dementia, researchers reported in Neurology.

May A. Beydoun, PhD, MPH, of the NIH’s National Institute on Aging, and colleagues examined associations of nutritional biomarkers with incident all-cause and Alzheimer’s disease dementia among American adults aged 45 years and older.

“Extending people’s cognitive functioning is an important public health challenge,” Beydoun said in a related American Academy of Neurology press release. “Antioxidants may help protect the brain from oxidative stress, which can cause cell damage.”

Beydoun and colleagues used data from the National Health and Nutrition Examination Survey from 1988 to 1994 and linked it with Medicare and Medicaid follow-up data. From there, researchers tested associations and interactions between serum vitamins A, C and E, as well as total and individual serum carotenoids and interactions with incident AD and all-cause dementia.

A total of 7,283 participants were included, all of whom had a physical exam, interview and blood test for antioxidants. They were followed for an average of 16 years to determine who developed dementia.

Researchers found that increased levels of antioxidants lutein and zeaxanthin were associated with a reduced risk for all-cause dementia in people aged 65 years and older (HR = 0.93; 95% CI, 0.87-0.99) and that increased beta-cryptoxanthin levels reduced the risk in those aged 45 years and older (HR = 0.86; 95% CI, 0.8-0.93).

According to the release, lutein and zeaxanthin are found in green, leafy vegetables such as kale, spinach, broccoli and peas, while beta-cryptoxanthin can be found in fruits, such as oranges, papaya, tangerines and persimmons.

“It’s important to note that the effect of these antioxidants on the risk of dementia was reduced somewhat when we took into account other factors such as education, income and physical activity, so it’s possible that those factors may help explain the relationship between antioxidant levels and dementia,” Beydoun said.

References:

Higher antioxidant levels linked to lower dementia risk. https://www.aan.com/PressRoom/Home/PressRelease/4984. Published May 4, 2022. Accessed May 11, 2022.