I have long heard about the health benefits of fish. I’ve also been aware that not all fish are equally good for you, and that overfishing is harming the oceans. Now, more fish news is on the radar: A new study highlights fish consumption as a way to get protection from diabetes, and another report compiles the fish that are the most healthful and that can be caught with the least effect on the environment.
Fish and Diabetes Risk
As part of a cancer study called the European Prospective Investigation into Cancer and Nutrition, scientists in the United Kingdom followed roughly 22,000 people ages 40–79 years for about 10 years. Participants reported on their lifestyles by answering a questionnaire.
Published in Diabetes Care, the study found that consuming fish once or more per week may reduce the risk for Type 2 diabetes. The researchers conclude, “Total intake of both white fish and oily fish was associated with a lower risk of diabetes, reinforcing the public health message to consume fish regularly.”
The message about the health benefits of fish is not new, of course. Diabetes Self-Management’s Amy Campbell has reported on it several times. The popular Mediterranean diet features fish and has been found to lower heart disease risk. Dariush Mozaffarian, MD, DrPH, a professor at Harvard, says that an average of one serving of salmon a week lowers the risk of heart disease by 36%. (Perhaps it’s a very large serving.)
The study also found that eating shellfish was actually associated with an increased diabetes risk. The study’s authors thought this might be due to cooking methods and called for more investigation.
Weight may be a factor in the results. The authors write that, “The associations between white fish and oily fish intake and diabetes risk were not significant after adjustment for [obesity.]” Possibly, they say, consumption of white and oily fish protects against Type 2 diabetes by helping control weight. More research is needed, they say. (Of course, that’s what they always say.)
Which Fish Are Oily?
Oily fish tend to be the ones a lot of us don’t like, the ones that taste “fishy.” I’m asking readers for ways of preparing oily fish that taste better, although we’ve published recipes here.
But what fish are considered oily? The UK Food Standards Agency lists salmon, trout, mackerel, herring, sardines, kipper, eel, whitebait, tuna (fresh only), anchovies, swordfish, carp, orange roughy, sprats, and several others I never heard of. Maybe they’re English fish.
The list of white fish includes sole, halibut, catfish, snapper, sea bass, tilapia, and about 30 others. Check them out for yourself.
Are Fish Safe?
Our oceans and lakes are increasingly polluted, which means that fish can be contaminated as well, as I wrote about last week. The well publicized risk of mercury contamination has caused many people to question how much fish they should eat. Professor Mozaffarian is now beginning to study whether the contamination in seafood outweighs the benefits.
Mercury levels tend to be highest in the large “top of the food chain” predators like tilefish, swordfish, and shark. Smaller fish like herring and sardines have much lower levels. Mercury is more of a problem for women who might become pregnant, women who are pregnant, nursing mothers, and children.
Also, some fish are higher in healthful omega-3 oils , while other fish have more omega-6 oils, which are consumed excessively in the typical American diet. And bad fishing practices have caused great destruction to our oceans.
In response to these issues of oils and overfishing, the Monterey Bay Aquarium has come out with a “Super Green Healthy Seafood List.” (I really think they could have come up with a better name. Who wants to eat green fish?) The list classifies fish by their healthful oil content, level of contaminants, and the environmental effects of catching them.
Julie Packard, the aquarium’s executive director, said she and her colleagues published the list because “seafood choices are often the easiest way to get Americans thinking about broader ocean-policy questions.”
The list can be seen here. It does not calculate the relative health benefits and risks of eating a specific type of fish, but features species with high levels of omega-3 acids and relatively low contaminant levels.
The list of healthful fish that are also safe for the environment includes: pole-caught albacore tuna, wild-caught pink shrimp and Pacific sardines, Dungeness crab, and some other wild fish, as well as some farm fish — rainbow trout, bay scallops, and crayfish, among others.
Some people don’t like the taste of fish, and for others it seems too expensive. Due to the subsidies our government gives meat production, meat can be bought cheaper than fish as a protein source. And vegetarianism is always an option. But there may be ways of making fish more affordable — from catching your own to buying from a fish co-op.
Are you in the swim? Have you figured ways to get healthful fish into your diet? As the Mediterranean diet people are always saying, fish oils are among the most healthful foods you can eat. Do you agree? Let us know how fish fits in to your diabetes management plan.