Scraping the Bottom of the Nutrition Science Barrel

Who do you want giving you nutrition advice when youre pregnant, doctors and dietitians or a psychology student? If you trust a new study that eclipses the negligent rating and catapults itself into ranks of the straight-up-wacky, youd pick the psychology student.

The study is published in the little-known Nutrition Journal, not to be confused with the venerable Journal of Nutrition. A distinction most aptly illustrated with an eighties sports car reference that would compare a Fiero and a Ferrari.

The study, titled Consumption habits of pregnant women and implications for developmental biology: a survey of predominantly Hispanic women in California, contains numerous recommendations that fly in the face of the most up-to-date nutrition science.

The entire study loses any credibility out the gate when the authors had to categorize foods into healthy or unhealthy. Lets see here, healthy, fresh fruit. OK. Unhealthy, sugary desserts. Im following. Healthy, milk. Sounds good. Unhealthy, tuna and salmon. Ummmm. Why? Well, we took a look at the studies the authors cite to justify categorizing these lean sources of protein and brain-nourishing omega-3s as unhealthy eating habits and heres what we found. They are, on average, at least a dozen years old and not a single one looks at the net effect of eating fish during pregnancy on babies. The most recent citation, from 2011, is not from a published study at all, but from the consumer buyers guide, Consumer Reportsalso a terrific reference for buying stereo equipment and computer printers.

At one point the authors point to the dangers of salmon for pregnant women because it contains polychlorinated biphenyls (PCBs). What the psychology students failed to note is that the highest contributors of PCBs and dioxins to the American diet are beef, chicken, and pork (34% of total); dairy products (30%); and vegetables (22%). All fish and shellfish contribute 9%. I guess based on this logic, pregnant women should stop eating vegetables.

While the authors categorize tuna and salmon as unhealthy eating habits, here are a couple groups that dont:

United States Department of Agriculture and United States Department of Health and Human Services 2010 Dietary Guidelines for Americans, January 2011

  • A panel of 13 nutrition experts and physicians reviewed 46 studies to reach the conclusion that intake of omega-3 fatty acids, in particular DHA, from at least 8 ounces of seafood per week for women who are pregnant or breastfeeding is associated with improved infant health outcomes, such as visual and cognitive development. Therefore, it is recommended that women who are pregnant or breastfeeding consume at least 8 and up to 12 ounces of a variety of seafood per week Women who are pregnant or breastfeeding can eat all types of tuna, including white (albacore) and light canned tuna, but should limit white tuna to 6 ounces per week because it is higher in methyl mercury Obstetricians and pediatricians should provide guidance to women who are pregnant or breastfeeding to help them make healthy food choices that include seafood.

World Health Organization and Food and Agriculture Organization of the United Nations Joint Expert Consultation on the Risks and Benefits of Fish Consumption, September 2011

  • A panel of 17 nutrition experts, physicians, and toxicologists reviewed nearly 150 studies and articles to reach the conclusion that experts should emphasize the net neurodevelopmental benefits to offspring of women of childbearing age who consume fish, particularly pregnant women and nursing mothers, and the neurodevelopmental risks to offspring of women of childbearing age who do not consume fish.

Oddly (or not, based on their opinions about fish) the researchers consider tap water and all canned foods unhealthy. Looks like a canned salmon sandwich with a glass of water is pretty much the kiss of death.

Dont get us wrong, this is a study worth reporting on. But the story is not that 25% of pregnant women eat salmon. The story is that studies like this that have the true potential to confuse and harm moms-to-be are a). allowed to be crafted by psychology students and b). get published in a nutrition journal.