Seafood can be a tasty source of protein that supports a healthy, balanced diet. But too much of anything is not always beneficial, say University of Florida researchers, who report on the findings of a new University of Florida study of seafood consumption in the journal Public Health Nutrition.
To assess health risks versus benefits of consuming certain seafood products, scientists analyze seafood for nutritional value such as omega fatty acids and possible contaminants, such as mercury. Coupled with an understanding of what people eat, how much they eat, and how often they eat it, scientists can gauge a risk level, University of Florida scientists say.
For example, scientists advise Americans to eat eight to 12 ounces of fish or seafood each week for their nutrient values. On the other hand, as recently as 2011, more than one-third of the country’s inland waterways were under fish advisories due to contamination, according to the U.S. Environmental Protection Agency; hence, the need to potentially limit consumption of certain fish to potentially vulnerable populations.
In 2010, people in many Gulf coastal communities grew concerned about seafood safety after the Deepwater Horizon oil spill. Dr. Anne Mathews, an assistant professor of food science and human nutrition with the UF Institute of Food and Agricultural Sciences, teamed up with Dr. Andy Kane, an associate professor of environmental and global health in the University of Florida College of Public Health and Health Professions, and a Florida Sea Grant agent, to help assess inshore-harvested seafood following the spill. Dr. Kane served as principal investigator for the five-year study addressing seafood safety in coastal Gulf communities, with support from the National Institute for Environmental Health Sciences.
In order to examine potential risk for coastal seafood after the oil spill, Dr. Kane and other UF scientists collected more than 900 seafood samples and processed them for contaminants. They surveyed people in Gulf coast communities, representing 930 household members, to learn patterns of seafood consumption. A key element needed for this effort was a tool to help survey participants accurately report how much Gulf seafood they actually eat.
As part of the larger grant, Dr. Mathews led research that examined how accurately people could report their seafood intake, based on photographs of different portion sizes of cooked seafood. In the study, Dr. Mathews conducted two identical projects, one with fish and one with shrimp.
The first study asked 54 participants to look at seven plates of freshly cooked shrimp, with portion sizes ranging from two to 16 ounces, and asked them to pick the plate with a portion size that they usually consume. The second experiment, with 53 participants, replicated the same procedures with fish.
Study participants later looked at photographs of plates with a range of portion sizes of plated, cooked fish and shrimp, and researchers asked them to pick the photo of fish or shrimp that reflected the portion size they usually eat.
“When we compared ‘typical portion size choices’ from study participants, we saw no differences between photographs of seafood portions with the actual plates of fish or shrimp portions,” Dr. Mathews said. “That means the photographs helped participants to accurately identify the portion of seafood they would usually consume.”
In fact, the photographic seafood portion guide worked well for 94 percent of participants, who chose their “typical seafood portion” photograph within two ounces of the actual plate of freshly cooked fish or shrimp they previously selected.