Researchers have said that for older people, a year of taking daily multivitamins had a similar effect to turning back the cognitive ageing clock by more than three years, and that it improved age-related memory loss.
They said this effect persisted for the length of the study, and that subjects with cardiovascular disease taking the multivitamins experienced the greatest improvement in memory, reports Medical News Today.
The research from Columbia University in New York and Brigham and Women’s Hospital/Harvard in Boston was published in the American Journal of Clinical Nutrition.
The study is a second, parallel trial accompanying the recently completed Cocoa Supplement and Multivitamin Outcomes Study Web, or COSMOS-Web study. Its larger aim was to investigate the beneficial memory effects of multivitamins and cocoa flavanols. But the current study reports only the effects of taking multivitamins.
For their study, the scientists randomly assigned 3 562 older adults to one of two groups. The first took a daily multivitamin – Centrum Silver for adults – over the course of the three-year study. The second group took a placebo.
Each year, participant memories were assessed via online neuropsychological tests. The researchers were primarily interested in measuring the strength of individuals’ episodic memory, or immediate recall.
After a year of taking multivitamins, participants experienced a modest improvement in memory that was the equivalent to turning back the clock by about 3.1 years compared with a control group.
The authors said the most significant memory improvement occurred in people with underlying cardiovascular disease. The reason isn’t clear, though the researchers suspect it may have to do with a pre-existing nutrient deficit.
As a secondary goal, the researchers also searched for changes in episodic memory over the study period, and participants’ performance of novel object recognition and executive function. However, they found multivitamins had no effect on these particular neuropsychological tasks.
Study co-author Dr JoAnn Manson, epidemiology professor at the Harvard TH Chan School of Public Health, told Medical News Today: “Preserving memory and cognitive health is a high priority for most midlife and older adults. Few previous strategies have been rigorously tested in randomised clinical trials and shown to have cognitive benefits.”
The results of the study are particularly persuasive in that they represent the concurrent findings from two separate trials at once.
Both found that multivitamins slowed down cognitive decline in the short, three-year term.
Dr Fernando Testai, professor of neurology at the University of Illinois and who was not involved in the research, said prior studies examining the preventive effects of vitamin and mineral supplementation on cognitive decline “have produced inconsistent outcomes”, and suggested such research is complicated by factors that may affect cognitive performance, including: genetic factors; coexisting vascular risk factors; social determinants of health; and unhealthy behaviours (i.e., sedentary lifestyle, alcohol use, and smoking).
How do multivitamins improve memory?
The study does not explore exactly which vitamins within the multivitamin played a role in supporting memory.
“Multivitamins contain more than 20 essential vitamins and minerals, and the specific micronutrient conferring cognitive benefits cannot be determined when a combination tablet is administered,” Manson said, adding that a daily multivitamin may be a good idea based on the COSMOS-Web studies.
Matthew Pase, PhD, associate professor at the Turner Institute at Monash University and Harvard TH Chan School of Public Health who was not involved in the study, noted that “boosting cognition in the short term is rather different to preventing cognitive decline in the long term, and there are few long-term randomised controlled trials”.
He said the study was valuable but he would not recommend multivitamins for slowing cognitive decline, and that their benefit in the study was limited to just one cognitive area, that he would prefer to see the results of longer studies and “improvements on a greater range of cognitive tasks”.
“It is important to note that not all vitamin supplements (or even multivitamins) are created equal.” Indeed, dietary supplements, including multivitamins, are not approved by the US Food and Drug Administration (FDA) for safety or effectiveness.
Testai cautioned that “excessive levels of certain micronutrients, especially fat-soluble vitamins, lead, and iron, can lead to toxicity”.
Still, Manson was less concerned, pointing out: “An advantage of multivitamins is that these supplements provide daily intakes and do not involve mega-dosing. Multivitamins (and other dietary supplements) shouldn’t be perceived as a substitute for a healthy diet or healthy lifestyle, even if used as a complementary approach.”
Study details
Multivitamin supplementation improves memory in older adults: A randomised clinical trial
Lok-Kin Yeung, Daniel Alschuler, Melanie Wall, Howard Sesso, JoAnn Manson, Adam Brickman, et al.
Published in The American Journal of Clinical Nutrition on 24 May 2023.
Abstract
Background
Maintenance of cognitive abilities is of critical importance to most older adults, yet few effective strategies to slow cognitive decline currently exist. Multivitamin supplementation is used to promote general health; it is unclear whether it favourably affects cognition in older age.
Objective
To examine the effect of daily multivitamin/multimineral supplementation on memory in older adults.
Methods
The COcoa Supplement and Multivitamin Outcomes Study Web (COSMOS-Web) ancillary study (NCT04582617) included 3 562 older adults. Participants were randomly assigned to a daily multivitamin supplement (Centrum Silver) or placebo and evaluated annually with an internet-based battery of neuropsychological tests for three years. The pre-specified primary outcome measure was change in episodic memory, operationally defined as immediate recall performance on the ModRey test, after one year of intervention. Secondary outcome measures included change in episodic memory over three years of follow-up and changes in performance on neuropsychological tasks of novel object recognition and executive function over three years.
Results
Compared to placebo, participants randomised to multivitamin supplementation had significantly better ModRey immediate recall at one year, the primary endpoint (t(5889) = 2.25, p = 0.025), as well as across the three years of follow-up on average (t(5889) = 2.54, p = 0.011). Multivitamin supplementation had no significant effects on secondary outcomes. Based on cross-sectional analysis of the association between age and performance on the ModRey, we estimate that the effect of the multivitamin intervention improved memory performance above placebo by the equivalent of 3.1 years of age-related memory change.
Conclusions and Relevance
Daily multivitamin supplementation, compared to placebo, improves memory. Multivitamin supplementation holds promise as a safe and accessible approach towards maintaining cognitive health in older age.
COSMOS – COcoa Supplement and Multivitamin Outcomes Study (Open access)
See more from MedicalBrief archives:
Daily multivitamin may slow cognitive decline – randomised US study
Report pans supplements for brain health as ‘huge waste of money’
Daily multivitamins linked to slower cognitive ageing — COSMOS-Mind study