Risk of dementia linked to antioxidant levels

Observational studies have shown that the risk of dementia was associated with blood levels of certain antioxidants.

May Beydoun, PhD, and MPH of the NIH National Institute on Aging in Baltimore, Maryland report that higher serum levels of lutein + zeaxanthin and beta cryptoxanthin (two carotenoids) reduce the risk of developing dementia. increase. colleague, Neurology..

Adjusted analysis weakens findings and suggests that socioeconomic status, lifestyle, and dietary quality may mediate the association.

When oxidative stress occurs at abnormally high levels, consuming antioxidants can help protect the body’s cells, including brain cells, from damage, says Badun. “Carotenoids, the pigments found in orange and yellow plants, are converted to vitamin A in the body. The most important carotenoids that may protect the brain could be lutein + zeaxanthin and beta cryptoxanthin. There is, “she said. Today’s MedPage..

“Unlike other studies, we did not analyze dietary intake levels of antioxidants and carotenoids. Instead, we analyzed levels of antioxidants and carotenoids in the blood,” Beidun pointed out. ..

“This is the first nationally representative study to do so on the risk of dementia,” she said. “This may be a better representation of the actual antioxidant levels than a person’s report of what foods they are consuming on a regular basis. The simple fact is the onset of dementia. May explain why the results of dietary comparison studies are mixed. “

Nutritional and dietary ingredients may be potential targets for the risk of dementia in the future, but previous observational studies have shown inconsistent results, Babak at the Karolinska Institute in Stockholm. Hooshmand, MD, PhD, MPH and Miia Kivipelto, MD, PhD said.so Ancillary editorial..

“For example, total dietary carotenoid consumption, especially lutein + zeaxanthin and lycopene, has a reduced incidence of Alzheimer’s disease. Rush memory and aging project I’ve been followed up for over 7 years. “

However, some longitudinal studies on dietary composition and dementia have been reported. Null result, They observed. “The possible explanations for discrepancies are different considerations for study design and population heterogeneity, differences in antioxidant status and eating habits, and potential confounders,” the editor writes.

Beydoun et al. Used data from 7,283 participants in the 3rd National Health and Nutrition Examination Survey (NHANES 1988-1994), linking that information with the records of the Centers for Medicare & Medicaid Services to identify cases of dementia for up to 26 years.

Participants were 45-90 years old at baseline and had an average follow-up period of 16-17 years. At baseline, participants had no dementia and had physical examinations, interviews, and blood draws.

Included findings:

• Among people over the age of 65, serum lutein + zeaxanthin was associated with a reduced risk of dementia due to all causes in a lifestyle-adjusted model (SD, HR 0.93, 95% CI 0.87). -0.99, P= 0.037) and socioeconomic status (HR 0.92, 95% CI 0.86-0.93, P= 0.013).
• Serum beta cryptoxanthin showed an inverse association with all-cause dementia in age- and gender-adjusted models over 45 years (HR 0.86 per SD, 95% CI 0.80-0.93, P<0.001) and 65 years and older (HR 0.86, 95% CI 0.80-0.93, P= 0.001). This association was also found in models tailored to socio-economic conditions (HR 0.89, 95% CI 0.82-0.96,). P= 0.006), but not so strong in subsequent models.
• No association with lycopene, alpha carotene, beta carotene, or vitamins A, C, or E was found in the fully tuned model. Antagonistic interactions are found in vitamin A and alpha carotene, vitamin A and beta carotene, vitamin E and lycopene, and lycopene and beta carotene, where one antioxidant exerts a protective effect at low levels of the other. Suggests.

Green leafy vegetables such as kale, spinach and broccoli are sources of lutein + zeaxanthin, while beta cryptoxanthin is found in fruits such as oranges, papayas and tangerines.

“The message to take home is that a healthy diet rich in carotenoids and antioxidants from dark leafy vegetables and orange-colored fruits, with or without antioxidant supplements, is at risk of developing dementia. It may be reduced, “said Beidun. “But the only way to prove the relationship between carotenoids and brain protection health is in long-term randomized clinical trials with antioxidant supplements to see if the number of people who develop dementia decreases over time. It is to confirm. “

“Also, importantly, it’s not yet known what levels of antioxidants need to be consumed daily through foods, beverages and supplements to promote healthy brain aging,” she said. I added. “Further research is needed to establish the amounts of antioxidants needed to promote brain health and healthy aging.”

Researchers pointed out that the limitation of the study is that antioxidant levels are based on one measurement and may not reflect lifelong habitual intake. Inverse causality may also have influenced the findings.