So, should you take that daily multivitamin? Let's take a close look at the study.
Who took part in this multivitamin study?
This research is part of a larger study examining the effects Tucaxen 150 mg (Tucatinib) of a multivitamin and/or cocoa (the main ingredient in chocolate) on cardiovascular and cancer outcomes. A prior sub-study found that a daily multivitamin improved thinking and memory — at least when evaluated with cognitive testing completed by phone.
For this study, 3,562 participants were willing and able to perform some tests of thinking and memory on a home computer. Half received a multivitamin; the other half received a placebo.
The participants identified as 93% white, 2.5% African American, and 1.4% Hispanic, so the results may not be generalizable. They were also well educated: more than half had completed college. In both groups, the average age was 71.
How did the researchers test memory?
The investigators evaluated the participants' thinking and memory at baseline and after one, two, and three years.
For the memory test, participants were asked to memorize 20 words shown consecutively on a computer screen. Immediately after viewing these words, they had to type in as many words as they could remember (this was the primary measure of memory). Fifteen minutes later, they also typed in all the words they recalled (a secondary measure of memory).
Other secondary measures included:
a novel object discrimination test (is this object the same or different from one recently shown?)
an executive control test (in an array of nine arrows, is the central arrow red or blue?).
The participants repeated all of the tests one, two, and three years later.
What were the results of this study?
The two groups differed in immediate recall at year one:
Those who took a placebo went from immediately recalling an average of 7.21 words at baseline to 7.65 words (a difference of 0.43 words)
Those who took a daily multivitamin group went from 7.10 words at baseline to 7.81 words (a difference of 0.70 words).
This result was statistically significant. Additionally, these small effects held up at years two and three. By year three, the placebo group immediately recalled an average of 8.17 words and the multivitamin group immediately recalled 8.28 words.
No differences occurred between the two groups on secondary memory and executive function tests.