The American Dietetic Association’s new position on nutrient supplementation

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As of September 2017, new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Check out my bestselling new book on the science of endurance, ENDURE: Mind, Body, and the Curiously Elastic Limits of Human Performance, published in February 2018 with a foreword by Malcolm Gladwell.

- Alex Hutchinson (@sweatscience)

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I’ve written a bunch about supplements recently, but bear with me for one more quick post. The American Dietetic Association just released its new position stand on “nutrient supplementation.” (The full text is available here.) A few interesting nuggets in there — for one, they note that supplement sales in the U.S. totalled an astounding $23.7 billion in 2007. About half of Americans take dietary supplements, and in particular about a third take a multivitamin/mineral (MVM). However you slice it, that’s a lot of money.

The basic gist of the position stand is as follows:

It is the position of the American Dietetic Association that the best nutrition-based strategy for promoting optimal health and reducing the risk of
chronic disease is to wisely choose a wide variety of nutrient-rich foods. Additional nutrients from supplements can help some people meet their nutrition needs as specified by science-based nutrition standards such as the Dietary Reference Intakes.

Pretty basic stuff. As you read further, it gets a little more forceful:

Although MVM supplementation can be effective in helping meet recommended levels of some nutrients, evidence has not proven them to be effective
in preventing chronic disease
. A study published in 2009 from the Women’s Health Initiative found no association between MVM supplementation and cancer or cardiovascular disease risk or total mortality in postmenopausal women…

They then do a pretty good job of summing up the evidence for and against various health claims, like vitamin B-12 and cognitive function, vitamin D and bone health and so on. If you’re taking vitamins, it’s worth a look to see what they have to say about the benefits you’re looking for (though it’s a far from comprehensive list).

The bottom line for me (as I ranted in a recent comment) is that supplements offer many people a false sense of security with, in many cases, very little evidence to back them up. Eating enough fruits and vegetables is a real challenge — one that I certainly struggle with, especially at this time of year — but I’m not sure it’s helpful to convince ourselves that coming up short doesn’t matter because we’re taking some pills that will compensate.

Jockology: vitamin C may slow muscle recovery and inhibit fitness gains

THANK YOU FOR VISITING SWEATSCIENCE.COM!

As of September 2017, new Sweat Science columns are being published at www.outsideonline.com/sweatscience. Check out my bestselling new book on the science of endurance, ENDURE: Mind, Body, and the Curiously Elastic Limits of Human Performance, published in February 2018 with a foreword by Malcolm Gladwell.

- Alex Hutchinson (@sweatscience)

***

This week’s Jockology column delves into the highly controversial body of research on antioxidants and exercise:

The question

How do antioxidants affect my workout?

The answer

Sales of orange juice are soaring as people seek flu protection from vitamin C, The Globe and Mail reported last month.

Old habits die hard, and our faith in the power of antioxidants is deeply entrenched. Over the past few years, a vast series of studies involving hundreds of thousands of subjects have failed to find any health benefits from antioxidant supplements.

Now, a handful of studies suggest that popping these pills may even block some of the benefits of exercise, and even slow down post-workout muscle recovery. [read on…]

Not to spoil the ending, but to me this research is yet another reason to focus on meeting nutritional needs by eating good foods (in this case, fruits and vegetables) rather than by swallowing pills.