The Archives of Internal Medicine recently released a new study, “Dietary Supplements and Mortality Rate in Older Women,” that suggested older women taking a multivitamin were at an increased risk of dying from cardiovascular disease or cancer.
However, this was only an observational study and not a rigorous test (randomized clinical trials are the gold standard). From observational studies we cannot draw conclusions about cause and effect, so this study doesn't prove that multivitamins cause cardiovascular disease and cancer. Even the researchers concluded that “it is not advisable to make a causal statement of excess risk” based on the outcome of this study.
It's true that some nutrients in multivitamins, including minerals like iron and copper, and fat-soluble vitamins A, D, E and K, can be toxic in high doses. So it's important to discuss dosages and potential interactions with a naturopathic doctor before starting any supplement, even multivitamins. (Naturopathic physicians are the
only doctors routinely trained in nutritional medicine and nutrient-herb-drug interactions.)
People who benefit most from taking MVMs include:
- People who do not eat enough fruits and vegetables
- Growing children
- Vegetarians and vegans
- Couples planning to conceive
- Pregnant and breastfeeding women
- Older adults
- People who have an increased need for nutrients due to chronic medical conditions or prescription medications
When it comes to selecting supplements, it's important to remember that product quality varies. Consumerlab.com found that "one out of four supplements either doesn't contain what it claims or has some other problems such as contamination or the pills won't break apart properly."
To ensure that products have been tested by an independent lab, look for seals from independent organizations like
- The United States Pharmacopeia
- The National Nutritional Foods Association
- Consumer Lab
- National Sanitation Foundation International