MEDICAL MODEL
nutrition

Help! Nutrition TMI

How do we wade through a sea of information. . . and misinformation?

KIMBERLY K. REED, O.D., F. A. A. O.

Several times a week, my inbox grows with nutritional product direct-marketing ads. Also, I receive many nutrition “forwards” from those who know I am deeply interested in nutrition. And, of course, I try to keep up with the peer-reviewed scientific literature regarding nutrition, which is published at increasingly shorter intervals.

I am constantly bewildered by what appears as a desperate competition to have the final, authoritative answer to what supplements we should take. Such advice comes from every direction — even unlikely sources, such as financial websites — at a frenetic pace. And worse, the information on one day may be completely contradictory to that on the next.

So, how do we wade through this sea of information and, often as not, misinformation?

Consider the source.

Patients — and even O.D.s — often aren’t aware that all nutrition information isn’t sourced directly from the literature.

For example, I was recently interviewed by a writer tasked with making a “top-10 eye foods” list for a popular non-health related website. Her editor, who had no experience in healthcare or nutrition, gave the writer a list of foods about which to ask. (I was able to disabuse her that chicken is an eye food.)

Get the full story.

After the AREDS2 data was released, several of the medical journal compilation services inappropriately reported, “antioxidants had no effect on preventing AMD” and made similar erroneous conclusions. This type of “abstract mining” doesn’t tell the full story, and therefore, can result in patients failing to receive the benefit of the scientific discoveries reported within the study’s body. In other words, read the original source literature.

Understand the study’s design and intent.

Is the study a randomized clinical trial or an observational study? Are the results given by patient report or via serum or intracellular nutrient analysis? Is more than one study reflected in the paper, in a meta-analysis? A meta-analysis combines multiple papers with the same general study aims to see whether deeper trends emerge or disappear when you combine the studies. The problem: When doing so, having identical study protocols is nearly impossible.

For example, in nutritional metaanalysis, one study might compare nutritional/food intake of a certain nutrient, while another study may supply the nutrient in supplement form. These studies might appear as looking at that specific nutrient’s effects, but in fact they are very different.

Also, one study might look at a disease outcome and compare a patient’s recollection of their frequency of intake of certain foods. And another study in the metaanalysis might look at healthy people taking supplements and then after several years see how many of them developed the disease. Cause and effect are notoriously difficult to establish using food and nutrition, and it muddies the waters even more when different studies are combined.

Due diligence required

Authoritative, non-biased nutrition, ocular and systemic health sources are needed. Until then, be sure to thoroughly read papers published in reputable journals and draw our own conclusions relevant to your own patient base. OM

DR. REED IS THE DIRECTOR OF THE OCULAR NUTRITION CLINIC AT NOVA SOUTHEASTERN UNIVERSITY’S THE EYE CARE INSTITUTE IN FORT LAUDERDALE, FLA. E-MAIL HER AT KIMREED@NOVA.EDU, OR SEND COMMENTS TO OPTOMETRICMANAGEMENT@GMAIL.COM.