Fish, Health, and Sustainability

The Scientific Paper:

Anthony J. McMichael and Colin D. Butler. American Journal of Preventive Medicine. (Am J Prev Med) Nov 29 (4) pp. 322-323. 2005.

Review This Scientific Paper’s Abstract:
http://www.eurekalert.org/pub_releases/2005-10/ehs-fig101705.php

The Purpose of this Study:
To comment on several peer-reviewed scientific papers published in the November, 2005 edition of the American Journal of Preventive Medicine. These several scientific papers report on the good and bad points of eating fish.

Some Background, Methods, Results, Caveats, and Other Select Points:

• Two Australian scientists wrote this comment that was published in a peer-reviewed, scientific journal in 2005.
• Fish provide 17% of the total animal proteins - plus 6% of all types of animal and plant proteins - eaten by people.
• Health risk assessment has become an increasingly sophisticated, policy-supportive procedure over the past 20 or more years.
• There is now plenty of evidence that eating fish - either as part of a Mediterranean-type (or Japanese) diet or as a specific food item - reduces the risk of certain kinds of heart disease.
• More specifically, there is a lot of scientific evidence from both animal and human scientific studies that certain, good, fatty acids – sometimes popularly referred to as “fish oils” - reduce various bad effects on your heart. These bad effects that are reduced include:

  1. Certain irregular heart beats;

  2. Fatty plaques that can block some of your blood vessels;

  3. High blood pressure; and

  4. Problems with blood clotting.

• Eating certain fish is good for the developing brain of both the unborn child and the infant.

• Eating fish may also be good for the old person’s brain.

• These two scientists wonder that if women of childbearing age (and other people) do eat less fish with high levels of methylmercury, will that high methylmercury fish then be instead sold to poor people and/or to export markets? And if this happens, then will these other people suffer from their resulting increased methylmercury exposure?

• These two scientists believe that health risk assessment must now cast a wider net for yet other reasons. Certain scientists recognize - but do not discuss - the wider global impact of eating fish. Eating fish is good for you, but eating too many fish too fast is bad for the Earth. Catching virtually all of the fish in the oceans will be very bad for people everywhere because it will sooner-than-later eliminate all health-supporting properties of eating fish. The poorest, fish-dependent people of the world will be the hardest hit.

• Globally, ocean fish and shellfish production has increased over fivefold from around 20 million metric tons in 1950 to about 105 million metric tons during the next 50 years. While the number of caught ocean-fish decreases, the number of people increases.

• Farm-raised fish is the only way to maintain or increase the amount of fish for people to eat. More than 25% of both the total ocean fish harvest and the freshwater fish harvest comes from farm-raised fish. Fish are farm-raised in both saltwater and freshwater.

• Farmed-fish has some important public health issues:

  1. Various bad chemicals may contaminate some of the farm-raised fish;
  2. Farmed-fish routinely eat feeds containing some of the same antibiotics or types of antibiotics oftentimes used to treat bacteria-caused diseases in people. This can result in strains of bacteria forming that are no longer affected by these once-useful antibiotics; and
  3. There are varying amounts of different fats found in farm-raised fish fed increasingly on land-grown crops instead of the usual natural foods fish find and eat in saltwater and freshwater.
     
• Because several of these land-grown crops are lower in certain, good, fatty acids, the levels of these good, fatty acids in farmed-fish fed land-grown crops are likely to be lower than in wild-caught fish. This results in people getting less good fatty acids when they eat farm-raised fish.

A Bottom Line:

• The task for mercury-in-seafood risk communicators is clear in that individual scientists must discuss the results of each of their recent scientific studies with journalists so that the average consumer can also benefit from new scientific findings.
• The two Australian scientist authors end their comment with the philosophical thoughts and questions of whether the well-informed person who eats fish in the future may wish to consider not only both the likely methylmercury levels and amounts of good, fatty acids in their meals of fish - but also how their eating fish impacts the Earth. Perhaps the future, well-informed fish eater should also wonder if by purchasing only low methylmercury fish they are indirectly harming the good health of other not-so-well-informed and/or not-so-financially-well-off people who will then have only the high methylmercury fish – or no fish at all - to eat.

Find This Scientific Paper for Your Review:
Fish, Health, and Sustainability. American Journal of Preventive Medicine. (Am J Prev Med) Nov 29 (4) pp. 322-323. 2005.