You may wonder why we don’t just eat more fish to get the benefits of fish oil.  The answer is, unfortunately, simple: many of the fish we now find in the oceans, lakes, and streams around the world contain dangerously high levels of mercury and other toxins. For the record though, most high potency fish oils, go through a rigorous process recoming all traces of toxins, mercury and PCBs. Always check the manufacturer’s label for threir claims.

Fish that contain the highest level of mercury are larger and older sharks, swordfish, king mackerel, and tilefish. It is probably a good idea for most people to avoid eating these on a regular basis, certainly no more than a couple of serving a week. The health risks of these toxins may well outweigh the potential benefits of the fish oil we can get by eating more fish. What’s more, you would have to eat much more fish than is feasibly possible to help treat some of the many diseases for which high-dose fish oil is being used for today.

When taking fish oils, side effects can include increased burping, heartburn, abdominal pain, a fishy aftertaste and diarrhea. These side effects can be minimized if fish oil consumption is increased gradually and if supplements are taken with other food.  Because fish oil has blood-thinning properties, be very careful about taking it if you also take aspirin or prescription anticoagulants such as warfarin (brand name Coumadin), or if you’ve had a stroke or are soon to have surgery. Talk to your physician first. Fish oil may also be beneficial for kidney function in people taking cyclosporine, a medicine used to prevent organ transplant rejection, but discuss your situation with your physician before using it.

As with anything there are always cautions. In any case, a great rule of thumb is that, if in doubt, check with your doctor.