Tea and Coffee Reduce Mercury Concentration in Fish


Traces of harmful mercury make fish an unwise choice unless you happen to take coffee and tea with your sushi.

Researchers at the Université de Montréal report that when eating boiled or cooked fish with 250 milliliters of tea or coffee virtually eliminates exposure to mercury.

Tea or coffee ingested at the same time as raw fish reduced exposure by about 50 to 60 per cent. Frying or boiling independently eliminated about 50 to 60 percent.

The results, published in the journal Environmental Research, surprised researchers. Environmentalists have regulated but not rid the seas of mercury. This research suggests that pregnant women and other sensitive to its effects may once again consider dining on certain fish, such as tuna, which are known to contain potentially harmful concentrations of the heavy metal.

Marc Amyot, a professor of biological sciences at U de M told the Montreal Gazette, “The magnitude of the effect was surprising.” said Marc “We thought there might be a five- to 10-per-cent reduction (in the exposure to mercury). We don’t usually see such dramatic results,” said Amyot, one of the lead researchers on the study.

The study simulated human digestion of tuna, shark and mackerel each are oily fish that are predatory and concentrate mercury. Boiling or frying worked equally well and in combination with tea or coffee virtually eliminated exposure to mercury.

Amyot cautioned that more study is needed. Mercury is known to cause adverse neurological effects, negatively impacts the cardiovascular system and is a possible carcinogen.

Pregnant women in particular have been told to stay away from it as consumption of fish is considered the main form of ingestion-related mercury exposure.

“This is what you call a provocative study,” Amyot told the Gazette. "It opens the door to more research.”
“It’s important to balance the benefits of eating raw fish that isn’t full of oil,” he said.

Source: Montreal Gazette