I have been answering a lot of nutrition questions lately and one topic seems to keep coming up. Everyone wants to know about fish. We all know that it is healthy for you, but what about mercury levels? Are fatty fish OK to eat? These are a few of the questions I have been answering in the last few weeks. Hopefully, these topics will make a little more sense after reading this column.
Let’s begin with the assumption that fish is healthy for you. Fish is very high in protein, has very little fat and tastes great. So far, fish looks like a great choice. The case gets even stronger when we look at the type of fat that fish contains. Fish is particularly high in omega-3 fatty acids, which have been shown to help moderate cholesterol levels, reduce inflammation and decrease body fat. Fish still looks good so far.
Meanwhile, a lot of people are concerned about fatty fish. What is a fatty fish? Fatty fish live in cold water and need the extra fat to help stay warm. Some fish that have been labeled as fatty include haddock, halibut, salmon, tuna, herring and mackerel. While these fish do have higher levels of fat than other fish, the amount of fat is still very low when compared to beef. In my opinion, any fish is a great source of protein, even if it is a fatty fish.
So if fish is a wonder food, why do people worry about it? The simple answer is high mercury levels. Mercury is a toxic metal that is released into the atmosphere through industrial pollution. Many companies are taking steps to reduce this, but levels are still high. The mercury finds its way into the water and contaminates the food chain. As big fish eat smaller fish, their mercury levels increase. As fish get larger and larger, they are unable to reduce the mercury levels in their systems. This means that some of the fish we like to eat for their health benefits, such as tuna, have high levels of mercury.
Mercury has been shown to affect the nervous system. In high levels it affects fertility and blood pressure and can lead to memory loss. It is particularly dangerous for children and fetuses. Since children develop their brain and nervous system throughout the first few years of their lives, even low-level exposure can cause lasting problems. This can cause poor mental development, cerebral palsy, deafness or blindness. Other side effects include delayed walking and talking, shortened attention spans and learning disabilities.
While the effects of mercury can be frightening, it is important to remember that mercury levels in fish are low, and there are some that have virtually no mercury. The trick is knowing how often to eat fish so that mercury does not begin to accumulate in your body. The Food and Drug Administration recommends that pregnant women and children do not eat shark, swordfish, king mackerel or tilefish, as they are very high in mercury. The FDA also recommends that everyone limit their consumption of other species to two meals per week. This includes such fish as canned tuna, salmon, shrimp, etc. It is also important to recognize that farm-raised fish have virtually no mercury but may contain antibiotics.
Personally, I am not very scared of mercury in fish. People would be healthier if they incorporated more fish into their diet rather than less. Fatty fish are particularly high in omega-3 fatty acids and are a great source of protein. These benefits far outweigh any potential risk from mercury, as long as you limit your intake to two meals per week. The average American does not eat fish even close to twice a week, so the risk is essentially eliminated. It all comes down to that old axiom: everything in moderation.
Jared Carter, CSCS, is the owner of Move Forward Fitness Personal Training Studio, 1616 Walnut St. Visit www.moveforwardfitness.com to sign up for his free newsletter, or reach him at (215) 399-3541 or [email protected] [email protected]