Are Multivitamins Good or Bad for You?
Research published in the Annals of Internal Medicine show a slight increase of mortality among women who took multivitamins, vitamin B6, iron, magnesium, zinc and copper supplements. Is this the whole story?
Other recent research has found that multivitamin intake reduces inflammation, increases performance, reduces pain and anxiety, and increases strength and balance among older men and women. Which study is right?
The new study on multivitamin and mineral use among elderly women utilized the Iowa Women’s Health Study, which followed 38,772 women from the average age of 62 years old in 1986 through 2008. As of 2008, 15,594 of the women being followed died. That is 40.2% of the women.
At three points – in 1986, 1997 and 2004 – the women were questioned as to their supplement use. The women characterized their vitamin and mineral supplement use at that time.
At the end of the testing period, the supplement use was indexed against the deaths among the women. It was found that death rates were 6% higher among those women who said they took multivitamins regularly, 10% higher among those who said they took a vitamin B6 supplement regularly, 15% higher among those who said they took a folic acid supplement, 10% higher among those who said they took regular iron supplements, 8% higher for those who said they took magnesium supplements regularly and 45% higher among those claiming to take copper supplements regularly.
However, those who took calcium had a 9% lower mortality death rate than those who did not take calcium. These were of course compared to those who said they did not take those supplements.
To test their results, the researchers then broke down the results for iron and calcium use into smaller periods of use – namely 10 years, six years and four years. This analysis confirmed the results of the larger period study.
Other factors of the study
However, what does this study NOT isolate? A number of things that are common among people who take vitamin supplements regularly, most of which would significantly affect the mortality rates:
– Some who take regular supplements do not eat a proper diet. They feel that supplements replace their need to eat a balanced diet (low in saturated fats, high in fiber and high in natural antioxidants and other phytonutrients).
– Many who take regular supplements – especially those who also take isolated vitamins and minerals – take doses far higher than the recommended doses – thinking that more is better. Many of these vitamins will burden the liver and other organs as they attempt to balance the body’s nutrient levels, along with those nutrients that are not in the supplements.
– Many elderly persons who take multivitamins do not take food-based multivitamins. Rather, they will buy low-cost chemically-synthesized nutrients that are not well-utilized by the body. Examples of this include vitamin E (alpha-tocopherol only, in the synthesized form of rac-α-tocopheryl acetate) and vitamin D2. Meanwhile, the body best utilizes mixed tocopherol and tocotrienol forms of vitamin E as present in plant foods, and vitamin D3, as converted by the liver from sunshine.
– Many who take regular supplements feel that they replace a healthy lifestyle. As such, they may exercise less and live more sedentary lifestyles, thinking that their vitamins are giving them extra insurance.
These factors were not removed from the study, and because they were not removed from the study, the study cannot be considered a valid basis to say that taking a natural, food-based multivitamin, assuming nutrient doses are not too high, and assuming the taking of supplements is not seen as replacing eating a healthy diet or replacing a healthy lifestyle, is harmful.
Other research confirms multivitamins reduce inflammation
This is confirmed in a study published in the Journal Nutrition in September of 2011 by researchers from the University of Connecticut. This study followed 31 healthy, active men and women. The subjects were carefully and directly tested and monitored on their physical performance, bloodstream parameters, pain, joint pain, anxiety, jump power, grip strength and other parameters.
For the first 28 days, the group was given a placebo (no nutrients) supplement, as they were tested. After the first 28 days, they took a week off of the “supplements.” Then they embarked on a second 28-day period, this time taking a multivitamin supplement. The study was double-blind, so none of the researchers nor the subjects knew what was being given – multivitamin or placebo.
When the two periods were compared, inflammation markers significantly decreased during the multivitamin supplementation period compared to the placebo period. Strength and power increased among the multivitamin men. Pain and joint pain also decreased among the men during the multivitamin period. Anxiety decreased among the multivitamin women, and balance increased among the multivitamin women group. Other markers for blood health were also seen improved during the multivitamin period.
The researchers concluded:
“A multi-nutrient supplement is effective in improving inflammatory status in both men and women, markers of pain, joint pain, strength, and power in men only, and both anxiety and balance (a risk factor for hip fracture) in women. Therefore, a multi-nutrient supplement may help middle-aged individuals to prolong physical function and maintain a healthy, active lifestyle.”
Why the significant difference between these two studies? A more controlled study like this one allows investigators to control and eliminate other factors that may be at play. They are involved directly in the study so they can see the other factors involved.
The issue in the large questionnaire-formulated studies is that they do not do enough to control or even understand other factors at play. While they are impressive because they are large, that largeness can also produce large errors because of their large scope and lack of direct observation. This prevents accuracy in formulating a trustworthy result.
Furthermore, the result of the elderly women study is overwhelmed by the numerous studies that have found that balanced diets high in phytonutrients, fiber and healthy fats increase health and reduce risk of early death.
Dunn-Lewis C, Kraemer WJ, Kupchak BR, Kelly NA, Creighton BA, Luk HY, Ballard KD, Comstock BA, Szivak TK, Hooper DR, Denegar CR, Volek JS. A multi-nutrient supplement reduced markers of inflammation and improved physical performance in active individuals of middle to older age: a randomized, double-blind,placebo-controlled study. Nutr J. 2011 Sep 7;10:90.
Mursu J, Robien K, Harnack LJ, Park K, Jacobs DR. Dietary Supplements and Mortality Rate in Older Women: The Iowa Women’s Health Study. Arch Intern Med. 2011;171(18):1625-1633.