When you go to the doctor you expect to hear about your blood pressure, your weight, or your risk of STDs or heart attack. But your doctor should also be asking you how much fish you eat. FISH? Why fish? Well, from a health standpoint, this is a tricky one. Fish are a great source of protein. They are low in fat and high in omega-3 fatty acids, which have been shown to improve cardiac health and are essential for the developing brains of young children and the fetus in utero. The American Heart Association recommends eating fish twice a week, but most of us are not consuming enough to reap the benefits from those omega-3s.
Unfortunately, this healthy food source is often contaminated. When mercury is released into the atmosphere from coal-burning power plants, waste incinerators, and the rare volcano, it travels for miles and deposits in waterways where it is transformed into methyl mercury. This type of mercury accumulates in fish and as larger fish eat smaller fish, it concentrates up the food chain. When humans eat large fish who have fed off of smaller fish and have lived long lives, we may ingest unsafe levels of mercury. While there are no reports of mercury toxicity in healthy adults from eating commercial fish in moderation, adverse health effects from fish consumption among pregnant and breastfeeding women, young children, and populations that eat a lot of fish are a real concern.
Studies among island populations who eat a lot of seafood have shown lower scores on neurological testing among children who were exposed to mercury in utero. It has been estimated that 1,566 cases of mental retardation in the US are due to fetal mercury exposure from mothers’ fish intake. In adults, higher mercury levels have been associated with hypertension and cerebrovascular disease.
People who catch fish recreationally are at risk for health effects from mercury if they eat large amounts of their catch. Also, certain ethnic groups are at risk because they are accustomed to eating fish frequently.
What can you do?
Eat fish but choose wisely! Eating fish is important for your health. If you are a healthy adult, eat two meals per week of a variety of fish. If you are pregnant, breast feeding, or are planning a pregnancy soon, DO NOT EAT shark, swordfish, tilefish, or king mackerel. (Follow these same restrictions for young children.) You may eat two meals per week of a variety of fish. If you eat fish caught locally, eat only ONE meal per week or check the local fish advisory for more details. http://water.epa.gov/scitech/swguidance/fishshellfish/fishadvisories/advisories_index.cfm