The Latest Bad Rap on Supplements: What Does This Week’s Study Mean to Women?

Yesterday, I set out to write about the latest findings of a government-funded research study that concluded that in older women, several commonly used dietary vitamin and mineral supplements may do more harm than good; even, in some cases, causing a small increase in the risk of death.

Death?  Really?  From Vitamin B6 and multivitamins?

There must be more to this than was being reported, so I decided to go to the source, The Archives of Internal Medicine, where the findings were published,  and read the study myself.   Here’s what I learned.

First: The Facts

Researchers assessed the use of 15 vitamin and mineral supplements (including multivitamins, Vitamins B6, C and D, folic acid, magnesium, Iron and Calcium) in relation to total mortality in nearly 39,000 women in the Iowa Women’s Health Study. The participants were just under 62 years of age when they began the study in 1986.  Supplement use, which was self-reported via a health questionnaire three times over 19 years, was widespread among these women and increased over the years.

In yesterday’s news reports about this study, we learned that the researchers found a small increase in the risk of death among older women who took dietary supplements compared with those who didn’t.  However, what wasn’t reported in many news accounts was the fact that the women in the study who took supplements tended to be healthier, more physically active and had lower rates of diabetes and high blood pressure, with a lower BMI and waist-to-hip ratio than women who didn’t. Their diets were healthier too.  Nevertheless, the women who took an iron supplement or multi-vitamin showed an increased risk for early death. Those who self-reported that they took Vitamin B complex, Calcium and Vitamins C, D, E had significantly lower risk of death compared with non use.

Over the 19 year period that these 39,000 women’s histories were tracked, about 16,000 – or 40 percent – died. Yet, the research did not explore whether supplements contributed to their deaths.  That’s because they didn’t know why the women were taking the supplements in the first place.


So, can we conclude that vitamin and mineral supplements are a waste of money and even harmful. Does this study prove that the “try it, it can’t hurt,” attitude is old thinking?

The study’s first author, a researcher in nutrition at the University of Minnesota’s School of Public Health said, “this paper contributes to the growing amount of studies showing no benefits for supplement use in the prevention of chronic diseases. Millions of Americans take these, but there just don’t appear to be a lot of benefits.”

Bonnie Jortberg, a registered dietitian and senior instructor at the University of Colorado School of Medicine in Denver, said the research “bolstered arguments against using supplements other than in cases of known nutritional deficiency.”

Dr. David Heber, director of the UCLA Center for Human Nutrition, speaking to the  L.A. Times said, “I wouldn’t recommend anyone change what they’re doing based on this study. It’s very hard to conclude cause and effect.”

The Alliance for Natural Health, a non-profit organization self-described as “committed to protecting access to integrative medicine,” called this study “junk science.”  “To say the data is “unreliable” would be a generous description,” they wrote on their website yesterday. “In the study, all of the relative risks were so low as to be statistically insigificant. This kind of “data” has no place in a valid scientific study.”

IMHO, the findings of this study didn’t convince me that I should stop taking supplements. On the contrary, I feel better knowing that at least two of them, Vitamin D and Calcium, won’t likely be the cause of my death. Magnesium, which was among the 15 supplements assessed,  has helped reduce the frequency of leg cramps that wake me up at night.  So with a clear benefit for me, why should I stop taking this?

As with all studies, it makes you think about our own behaviors.  With so much money being spent on supplements — $11.8 Billion just last year, according to the Nutrition Business Journal –  maybe we should heed the advice of those scientists and medical professionals who say we should get all the nutrients we need from food whenever possible and only use supplements to correct diagnosed deficiencies.

What’s your take on this? Do you plan to cut back on the number of supplements you’re taking?


Related stories you might be interested in:

Use of Vitamins, Supplements Up

Vitamin Studies Spell Confusion for Patients

Do Vitamins Kill People? by Alan R. Gaby M.D.