Do multivitamins help with healthy ageing?

The strongest evidence for multivitamins in healthy ageing comes from memory research. In a large randomised trial (over 3,500 older adults taking a daily multivitamin for three years), participants scored better on episodic memory than the placebo group. The benefit was equivalent to reversing approximately three years of age-related memory decline, appeared after just one year, and was sustained thereafter. A pooled analysis of three sub-studies within the same research programme confirmed this picture consistently. Effects on other cognitive functions, such as object recognition or planning and organising, were not found.

For immune function the picture is more nuanced. If you are deficient in certain vitamins or minerals, that increases your susceptibility to infection and slows recovery. Supplementing up to recommended levels can correct that deficiency and improve your immune defences. Whether multivitamins also do anything in the absence of a deficiency has not been demonstrated. Bear in mind as well that the research behind this was funded by a multivitamin manufacturer, which puts the findings in perspective.

In the area of fall prevention, vitamin D is relevant for older adults in care settings who have a low vitamin D level. They fell on average about 37% less often. That sounds impressive, but the probability of having at least one fall at all did not change. Whether this also applies to community-dwelling older adults with a normal vitamin D level cannot be determined from these data.

Finally, animal studies and small-scale human studies are investigating specific supplements that may improve muscle cell function, including omega-3 fatty acids and several other compounds. These are not ordinary multivitamins, and the evidence is limited and early-stage. Long-term safety and efficacy have not yet been established, and several researchers in this field have financial ties to supplement manufacturers.