Multivitamin, mineral supplement may lower illness severity
Multivitamin and mineral supplementation may decrease the length and severity of illnesses such as respiratory infections in older adults, according to research published in Nutrients.
Researchers conducted a two-armed, parallel, randomized double-blinded study at a single center in Oregon to evaluate the impact of a multivitamin and mineral (MVM) supplement (Redoxon VI, Bayer) on the immune function of adults aged 55 years and older.
Participants were assigned to take a MVM supplement each day for 12 weeks or placebo. Three weeks before receiving treatment, participants were asked to restrict their diet to one 4-ounce serving of salmon, shellfish, beef, dark meat poultry, lamb and liver each week and to reduce their intake of citrus fruits and juice to two servings each day. They were also asked to stop taking multivitamins and food or beverages containing zinc, vitamin C and vitamin D.
A total of 42 adults aged 55 to 75 years were included in the study. They completed a diary each day to record their supplement intake and any symptoms of illness. Researchers collected blood and saliva from participants at baseline, week 6 and week 12.
Diary entries and samples were used to measure blood, mineral and vitamin status, immune function, immune status and self-reported health.
Researchers determined that immunity indictors, such as the ability of white blood cells to kill pathogens, did not change in the MVM group. They also found that participants in the MVM group had improved vitamin C and zinc status in their blood.
Participants in the MVM group reported less severe symptoms of illness. Although there was not a difference in the percentage of participants who reported illness, those in the placebo group were ill for a mean 6.43 days, while those in the MVM group were ill for a mean of 2.29 days.
Healio Primary Care spoke with Adrian F. Gombart, PhD, principal investigator at the Linus Pauling Institute and professor in the department of biochemistry and biophysics at Oregon State University, to learn more about the findings and the effects of MVM supplementation.
Q: How does this study differ from previous findings on multivitamins?
A: This study is different from previous ones in that it was assessing an MVM supplement formulated to support and improve immune function. The goal was to determine if the additional vitamin C in combination with other micronutrients and minerals that support immune function would affect immune cell function in MVM participants as compared to the matched placebo. We did not reach statistical significance in the immune cell tests, but we did observe shortened duration and severity in self-reported illness.
Q: The study population was small. What additional research is needed to evaluate the effectiveness of MVM supplements in older adults?
A: It is important to perform additional studies with larger populations and at more than one location that are designed to address improvements in clinical outcomes with more extensive surveys and, if possible, validation of illness by a physician rather than self-reported illness. We would like to identify changes in immune function that could explain how the MVM supplement is improving the clinical outcomes of these patients. The current study does not allow us to conclude that the supplement is modulating immune function to improve outcomes.
Q: Could MVM supplements provide similar results in younger populations?
A: That is an interesting question. We selected an older population as we know that deficiencies in vitamins and minerals are more prevalent in this population. I would expect that anyone with inadequate levels of a number of micronutrients could benefit from this sort of supplementation, but it remains to be tested.
Q: Based on the findings, should PCPs recommend that older patients take daily MVM supplements?
A: Based on this finding and those of previous studies, PCPs should assess the intake of micronutrients (vitamins and minerals) by their patients to determine if taking a MVM would benefit them. Eating a healthy diet is important, but one can use MVM and single vitamin or mineral supplements to compensate for shortfalls. In addition, it is always wise to assess vitamin D status as vitamin D is limited in the diet and requires adequate sun exposure, which is affected by climate and season.