Study shows increase risk of melanoma with fish consumption
You’ve added fish to your diet to eat healthy, but now a new study delivers some bad news: Fish lovers may have a slightly increased risk of melanoma.
Researchers followed over 490,000 older Americans and found the 20% with the highest intake had about a one-quarter higher risk of developing the disease over 15 years, versus the 20% with the lowest fish consumption.
Still, experts stressed the findings show only a correlation, and cannot pin the blame squarely on seafood.
An oncology dietitian who was not involved with the study emphasized the “bigger picture.”
In general, fish is a healthy protein source, often rich in anti-inflammatory omega-3 fatty acids, said Amy Bragagnini, of Mercy Health Lacks Cancer Center, in Grand Rapids, Michigan.
Because of its benefits — including links to better heart and brain health — experts generally recommend people strive for two 4-ounce servings of fish per week, noted Bragagnini, who is also a spokesperson for the Academy of Nutrition and Dietetics.
Fish can be a “great alternative,” she said, for people looking to limit red and processed meats — which are tied to higher risks of certain cancers, including colon and rectal cancers.
So why would fish be linked to melanoma, a disease most closely related to risk factors like sunburns and family history?
It’s not clear, said lead researcher Eunyoung Cho. But one hypothesis is that it’s the contaminants — like mercury and PCBS — that can exist at relatively high levels in some fish.
Past research has linked mercury exposure to a higher risks of melanoma and other skin cancers, noted Cho, an associate professor at Brown University’s Warren Alpert Medical School, in Providence, Rhode Island.
However, she said, the contaminant theory is just that. “This is the first study to show this association,” Cho said. “We need more research to replicate these findings before we can make any dietary recommendations.”
The findings were published in the journal Cancer Causes and Control.