Older people who take multivitamins are sick less often

Older people can easily become deficient of vitamins and minerals, which can weaken their immune system and make them more prone to infections and prolonged periods with disease. On the other hand, older people who take a multivitamin and mineral supplement with zinc and large quantities of vitamin C experience fewer days with disease and have less severe symptoms, according to a placebo-controlled study from Oregon State University. But many multivitamin supplements do not contain enough vitamin D and it is very important for older people to get enough of this nutrient.

It is a fact that older people can easily become deficient of vitamins and minerals as a result of eating too little, eating the wrong foods, having malabsorption problems or sluggish enzyme processes. In a new study from Oregon State University’s Linus Pauling Institute, 42 healthy participants aged 55-75 years were randomly assigned to a multivitamin and mineral complex or matching placebo for 12 weeks. The study was designed to measure how the supplement affected different parts of the immune system. The scientists also looked at blood levels of vitamin C, vitamin D, and zinc, as these nutrients are particularly important for the immune system.

Supplementing with multivitamins and minerals improves your health

There were equally many infections in the two groups. Most likely, this had something to do with the low vitamin D content in the supplement, which did not even affect blood levels of the nutrient. We will get back to that.
However, the supplemented group had increased blood levels of vitamin C and zinc. Interestingly, those taking supplements felt less sick and recovered faster than those on placebo. The subjects in the supplemented group had less than three sick days on average, while those in the placebo group had six. This difference is significant and suggests that the supplemented participants were able to fight their infections faster and with fewer and milder symptoms.
According to Professor Adrian Gombart from Oregon State University, the difference between the groups was striking. Although the study was limited and based on self-reported disease observations, the results speak their own clear language and warrant further research.
In the United States, Canada, and Europe, scientists assume that at least a third of older people lack one or several nutrients. The vitamin and mineral deficiencies among older people lead to impaired immune resistance. Both the innate and the adaptive immune systems are unable to function optimally, and the immune defense is not able to produce as many T cells, which constitute its special troops. This contributes to prolonged infections and other complications.
Professor Gombart says that older people can benefit from taking a daily multivitamin and mineral complex, but they should make sure to get all the different micronutrients that are known to boost the immune system. The supplement used in the study did not appear quite to cut the mustard.

Many multivitamin and mineral complexes need more vitamin D

The multivitamin and mineral complex used in the study from Oregon State University contained the following:

Vitamin A: 700 micrograms
Vitamin D: 10 micrograms (400 IE)
Vitamin: 45 mg
Vitamin B6: 6.6 mg
Folate: 400 micrograms
Vitamin B12: 9.6 micrograms
Vitamin C: 1,000 mg
Iron: 5 mg
Copper: 0.9 mg
Zinc: 10 mg
Selenium: 110 micrograms

If you compare with the recommended daily allowance (RDA) for nutrients and the Danish nutrient recommendations (RI – or reference intake), the supplement contains more vitamin E, vitamin B6, vitamin B12, vitamin C, zinc, and selenium than the recommended amount. Correspondingly, the scientists did measure increased levels of vitamin C and zinc in the blood of the participants in the supplemented group.
But they were not able to detect elevated levels of vitamin D in the blood, which is most likely because the 10-micrograms of vitamin D in the supplement were not enough to make a difference.
Many researchers claim that the need for vitamin D increases with age. In fact, they believe that we need as much as 40-100 micrograms of vitamin D from food, sunlight, or supplements, to reach optimal levels in the blood (60-100 nmol/l).
The optimal vitamin D levels are determining for the ability of the immune defense to function optimally in a number of ways, both the innate and the adaptive immune defenses. T cells use quite a lot of vitamin D to replicate swiftly and to direct swift attacks at virus and bacteria in the case of an infection.
If there is too little vitamin D in the blood, the immune system is unable to perform optimally. As seen in the new study, the ability of the immune defense to prevent infections in the supplemented group remained unchanged, although the infections were milder and shorter.
Always look carefully at the label when you buy a multivitamin and mineral complex to make sure that you get enough of the different nutrients. It may even be a good idea to take additional vitamin D and perhaps also vitamin C, zinc, and selenium to give the immune defense an additional boost.

References:

Mary L. Fantacone et al. The Effect of a Multivitamin and Mineral Supplement on Immune Function in Healthy Older Adults: a Double-Blind Randomized, Controlled Trial. Nutrients, 2020.

Oragon State University. Multivitamin, mineral supplement linked to less-severe, shorter-lasting illness symptoms. ScienceDaily, August 18, 2020

Carsten Carlberg, Afrozul Haq. The concept of the personal vitamin D response index. The Journal of steroid biochemistry and molecular biology. 2016

Robert Heaney, Cedric Garland and Edward Gorham: A Statistical Error in the Estimation of the Recommended Dietary Allowance for Vitamin D. J. Nutrients. 2014

Essen MR et al. Vitamin D controls T cell antigen receptor signaling and activation of human T cells. Nat Immunol 2010