In a recent study published in The American Journal of Clinical Nutrition, researchers investigate whether one year of supplementation with multivitamins could improve hippocampus-mediated cognition and memory in older adults.
Study: Multivitamin supplementation improves memory in older adults: a randomized clinical trial. Image Credit: photo_gonzo / Shutterstock.com
Healthy dietary patterns are associated with improvements in cognitive aging. Additionally, taking dietary supplements and vitamins daily is believed to delay the progression of cognitive impairment. While some studies have reported a link between cognition and vitamin B12 levels, randomized clinical trials (RCTs) and metanalyses report mixed results related to multivitamin supplements and cognition.
The Cocoa Supplement and Multivitamin Outcomes Study (COSMOS) examined the impact of multivitamin and flavanol supplements on cancer and cardiovascular outcomes in older men and women as compared to placebo. An ancillary study called COSMOS-Mind examined the impact of multivitamin supplements on cognition and compared it with the impact of the placebo.
About the study
In the present study, researchers examine whether supplementation with multivitamins was associated with improvements in memory and cognition in older adults. Participants were randomly assigned to either the placebo or multivitamin group consisting of Central Silver multivitamins.
A range of neuropsychological tests were included in the internet-based battery of tests administered for three years and used to measure outcomes such as changes in episodic memory or immediate recall performance, Changes in episodic memory were studied over three years of follow-up, as were novel object recognition and other neurophysiological tasks.
Women below the age of 65 years and men younger than 60 years were excluded from the study, as were individuals with a history of stroke or myocardial infarction, those with a recent cancer diagnosis or other serious illnesses, unwillingness to stop consuming cocoa products, multivitamins, or specific vitamins, sensitivity to caffeine, and an inability to speak English.
The performance during the immediate recall trial in COSMOS-Web, the internet-based set of neuropsychological tests, after one year of multivitamin supplementation, was the measured primary outcome. Secondary outcomes included immediate recall performance, memory retention, and novel object recognition in the second and third years of intervention.
The battery of cognitive tests comprised a 20-item test on word recall, where participants were required to type out the words they remembered with a greater than 80% match to account for typographical errors or differently spelled words. The words recalled immediately were considered the primary measure, while the words recalled after a delay was the secondary measure, known as retention. Immediate recall is related to the function of the hippocampus, while retention is associated with the function of the entorhinal cortex.
COSMOS-Web also contained a novel object recognition test that measured the reaction time required during recognition trials to reject lures, which was related to the function of the hippocampal dentate gyrus. A color or directional Flanker test was also included in these neuropsychological tests.
Study participants in the multivitamin supplementation groups exhibited significantly better performance in immediate recall tests than those assigned to the placebo group. These differences were observed after one year of intervention, as well as over years two and three. However, secondary outcomes such as executive function, memory retention, and novel object recognition did significantly improve after supplementation with multivitamins for three years.
The improvements in memory performance after multivitamin supplementation as compared to the placebo were equal to 3.1 years of memory changes related to aging. Since the participants in the multivitamin supplementation and placebo group had similar baseline dietary patterns, differences in dietary quality could not have confounded the results.
Furthermore, blood tests revealed that vitamin B12, folate, and 25-hydroxyvitamin D (25(OH)D) or serum 25(OH)D were all slightly elevated in the participants from the supplementation group as compared to the placebo group. Thus, further studies are warranted to examine the nutrients or nutrient combinations that improve cognitive health with respect to age.
Regular multivitamin supplementation in older adults resulted in improvements in cognitive function as compared to the placebo. Since vitamins generally have no adverse effects and are relatively less expensive, they provide a potentially sustainable health intervention to improve cognitive function in individuals as they age.
- Yeung, L., Alschuler, D. M., Wall, M., et al. (2023). Multivitamin supplementation improves memory in older adults: a randomized clinical trial. The American Journal of Clinical Nutrition. doi:10.1016/j.ajcnut.2023.05.011