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The COSMOS-Mind trial was funded by the National Institute on Aging to see if cocoa flavanols or multivitamins could help people stay mentally sharp as they age.


“We enrolled 2,262 participants aged 65 or older who were in the parent trial,” says Laura Baker, professor of gerontology and geriatric medicine at the Wake Forest School of Medicine.

“We administered a cognitive assessment on the phone, which took about an hour. And then we repeated the assessment every year for three years.”

The tests weren’t easy.

“We pushed the envelope on cognitive testing,” notes Baker. “Simple tests are not very useful. If it’s too easy, everybody gets 100 percent correct. But if it’s too challenging, very few people get a correct score. So you have to find that sweet spot.”

The results for cocoa flavanols

The cocoa flavanols flamed out.

“We were expecting to see something, because of promising evidence that cocoa flavanols may have beneficial cardiovascular effects,” says Baker.

“But we found there was no difference in test scores between participants who received the cocoa flavanols and those who received the placebo.”

CocoaVia bottle
The COSMOS trial saw signals that CocoaVia’s cocoa flavanols may protect your heart, but not your memory.
CocoaVia.

The results for multivitamins

Instead, it was the multivitamin takers’ scores that stood out.

“We were excited to see a significant improvement in cognition for folks who received the multivitamin,” says Baker.

“We saw a difference in global cognitive function and in tests of short-term memory and executive function, abilities that tend to decline with normal aging and with the development of Alzheimer’s disease and other forms of dementia.”

(Baker presented the results at a scientific meeting in November, but they hadn’t been fully published when this article was published.)

By the end of the three-year study, the multivitamin takers’ scores showed only 1.2 years—rather than 3 years—of cognitive decline.

“So the multivitamins cut 1.8 years of cognitive aging over the three-year trial,” says Baker.

Another interesting result: “People who had cardiovascular disease had a more potent response to the multivitamins,” notes Baker.

(That included people who entered the study taking statins, with plaque buildup in their arteries, with angina, or with a history of artery or heart surgery. People with a prior heart attack or stroke were not eligible.)

That matters, says Baker, because “we know these people are at higher risk for cognitive decline, and we currently have very little to offer them.”

Nevertheless, she cautions, “our findings need to be replicated.”

What other research has found

Only one other long-term trial—the Physicians’ Health Study II—tested Centrum Silver on memory loss. After 8½ years, it came up empty.

“So the score is 1 to 1,” says Baker.

One key difference: “In the Physicians’ Health Study, the first cognitive assessment was, on average, 2½ years after the participants were randomized to start taking the multivitamin or placebo.”

In COSMOS-Mind, “we saw the biggest difference in the scores of the multivitamin compared to the placebo group between baseline and year two. The scores were stable after that. If we had completed our first assessment after 2½ years, we may not have seen a difference.”

What's next

The COSMOS-Mind team is already planning a new trial.

“We’re shooting for about 35 to 40 percent of the participants to have cardiovascular disease,” says Baker. “And we’ll have more diversity in terms of race, ethnicity, education, and economic status, so we’ll know that any benefits are accessible to everybody.”

Why might multivitamins matter?

“Many older adults are not at optimal nutritional status,” notes Baker. “That doesn’t mean they’re deficient, but they could be suboptimal. Maybe a simple multivitamin is enough to boost them back into the zone.”

Multivitamins aren’t a cure for memory loss, she emphasizes.

“But they may give you a layer of protection that can keep your cognitive function stable for a longer period of time.”

What’s more, taking a multivitamin like Centrum Silver is safe.

“Even if you don’t have Alzheimer’s in your family, cognitive decline affects all of us as we get older,” says Baker.

“No one can escape it. So anything that might give people a layer of protection and poses no risks is worth pursuing with a new trial.”