For most people, a long and healthy life is a matter of balancing risks against benefits in the choices we make every day.

The health benefits of certain choices are obvious: wearing seat belts, quitting smoking, and getting your children immunized are all choices where the benefits vastly outweigh the risks.

Similarly, the hazards of other choices are unmistakable: driving too fast, engaging in unsafe sex, and eating foods rich in saturated and trans fats are all choices that clearly put your health in peril.

But many choices that affect our health aren’t so clear-cut. One such conundrum is over fish in the diet. Conflicting reports in the media regarding the benefits and risks of eating fish have left the public confused and skeptical about the role of fish in a healthy diet.

What are the health benefits of eating fish? What are the risks from mercury and other contaminants present in many fish? Do the benefits surpass the risks? How can we get maximum benefit from fish consumption while keeping the risks acceptably low?

Recent scientific studies have examined these questions closely, and the evidence points overwhelmingly in favor of a modest intake of fish on a weekly basis. One or two servings of fish each week have tremendous benefits in preventing cardiovascular disease and other adverse health outcomes. For pregnant or breastfeeding women, such a diet also benefits the brain development of infants.

Eskimos and other indigenous people whose diets include large quantities of fish have traditionally had exceptionally low levels of cardiovascular disease. The coronary arteries of elderly Alaska natives collected in autopsies in the 1950s are as supple and free of disease-producing plaques as the vessels of young children.

The reason fish are so beneficial in the diet is the omega-3 fatty acids they provide. This is particularly true for oily fish such as salmon, sardines and herring.

People who eat one or two servings of these fish per week are 36 percent less likely to die from heart attacks. Their overall mortality rate is 17 percent lower than people who don’t eat fish as much.

Omega-3 fatty acids are nature’s wonder drug. Besides reducing heart attacks and all-cause mortality, they have been shown to lower blood pressure, reduce the heart rate, cut the risk of stroke, improve depression and slow the mental decline that can come with age.

One particular omega-3 fatty acid, known as DHA, is essential for neurological development during gestation and early infancy when the brain is rapidly developing.

The concern about eating fish centers on contaminants that accumulate in them over time. Mercury, by far the most serious offender, is spewed into the atmosphere by coal-burning industrial plants and volcanic eruptions. It is carried by air currents worldwide until it is deposited in the bottom sediments of oceans, lakes and rivers.

There it is converted by bacteria into a more toxic form, called methylmercury, which fish take in from their diet. Over many months or years, the methylmercury levels in fish can increase several thousand times higher than in the surrounding water. This is especially true for larger fish and for predatory species on top of the aquatic food chain.

Methylmercury was the culprit in Minimata Bay, Japan, where maternal consumption of highly contaminated fish from the polluted waters of the bay in the 1950s resulted in severe neurological defects in newborn children.

The amount of methylmercury typically consumed by avid fish eaters in America today probably has little, if any, adverse effect on men, and on women who are not of childbearing age.

But certain fish species, such as shark, swordfish, king mackerel and tilefish, have high enough methylmercury levels to warrant special concern.

A cautionary approach dictates that young children and women who are pregnant or breastfeeding - or women who may become pregnant - should avoid eating these fish. They should also avoid or limit their intake of certain freshwater fish caught by anglers in the Delta and other local lakes and streams. These species are listed at the web site: www.oehha.ca.gov/fish.html.

The bottom line: The benefits for everyone of eating all but a few species of fish, once or twice a week, are undeniable.

Pregnant women and young children also need fish in their diets, but they should steer away from fish known to have high methylmercury levels.

Following simple guidelines to avoid risks, we can all benefit from a diet that includes a healthy intake of fish.

- Dr. Eberhart-Phillips is the El Dorado County Health Officer. He can be reached at jeberhart-phillips@edcgov.us.

Source: El Dorado Hills Telegraph