Sunday, May 13, 2012

Basic Cooking: About Seafood

I think that eating seafood regularly is really important. Just as I strongly recommend regular liver consumption, shellfish or finfish (including roe) are on the menu at least once per week, and our favorite indulgent dinner is going out for sushi.

Why fish? First, let's get the mercury fears out of the way. Almost any fish you'd think of eating is safe. Essentially, fish isn't mercury and nothing else. It also contains selenium that protects against mercury. Real food is complicated and cool like that. Roe and shellfish are especially rich sources of cholesterol, which scares some people, but dietary cholesterol consumption has nothing to do with blood lipid profiles - and even there, it's much healthier to have cholesterol on the high side than to be deficient. You should avoid oxidized cholesterol (heat-damaged cholesterol), but that is unlikely to be a problem if you eat real food. Things like powdered eggs probably have lots of oxidized cholesterol, but then again, is it surprising that highly altered foods have been altered away from at least some of their goodness?

Anyway, on to the good stuff. Doubtless you have heard of the benefits of DHA and other omega-3 fatty acids as well as the importance of cutting out oils high in omega-6 fats that destroy the benefits of omega-3s. These omega-3 fats are not found in any plant foods whatsoever and we are really bad at putting them together ourselves. No, flax and other alleged plant sources contain zero omega-3s, only precursors that can be converted into omega-3s in limited amounts under the right conditions in healthy adults. That's a lot of qualifiers! Omega-3 fatty acids are found in healthy animal products of all kinds, but they are by far the most abundant in seafood. Suffice it to say that we can only count on preformed omega-3s for...well, I hate to call basic health a "benefit", because that makes it sound as if it is an optional bonus instead of normative. Know that pregnant and lactating mothers as well as infants and children have additional needs for preformed omega-3s, especially DHA. They, along with cholesterol, are essentially what our brains are made of. Seafood not the only source of this brain food but it is the best.

Additionally, among the various seafoods are the best or among the best food sources of zinc (from oysters), iron (from clams), vitamin B12 (especially in shellfish), vitamin D (from roe and from oily fish like herring, sardines, and mackerel), iodine, and selenium. Sea-dwelling creatures have mineral content that land animals living on depleted soils do not. These are all in their absorbable forms in fish. Plant sources are, unfortunately, not well digested by humans for most of these. "Bacterial sources" of vitamin B12 are different from actual B12 and these analogues actually make B12 deficiency worse!

Picking out quality fishies without breaking the bank is tricky. I sympathize with those who limit fish to save money or only buy cheap species of fish that are not very nutritious - tilapia, I'm looking at you, here - but my personal view is that it is deeply unwise to skimp too much on your health. It is such a blessing to have good health that, having been chronically ill from undiagnosed celiac disease in the past, I refuse to take health for granted anymore. So I am a big believer in investing wisely in your health. It is easy to underestimate the cumulative impact of genuinely good nutrition. If you are reading this blog, you can probably afford to eat a healthy diet.

In the U.S., decent fish may be $8/lb. and your typical protein $3/lb., and that makes fish sound so expensive that you never buy it. Think about it, though. That's $1-2 more per serving, so if you keep it to once a week, that is fabulous deal if you pick a nutritional powerhouse! Back when I ate a typical American diet, I didn't think badly of spending $1.25 on a soda a few times per week, and many people are OK with $4 coffee confections on a regular basis. Get the idea? I can tell you that I spend less than $5/week per person on large helpings of great seafood. Bright orange frozen salmon from Trader Joe's and fresh shellfish from a local fishmonger are very manageable where I live once you compare prices and consistently stick to the best deals. Knowing local prices also means I stock up in the event of a genuine deal.

But which seafood do we shell out the extra cash for? All are not nutritionally equal! We have all heard that wild-caught seafood is the way to go. There is truth to this, but it's more complicated than simply farmed vs. wild. Farmed tilapia from China is definitely a no-go, but for some species, farmed is actually better! Plus, in some cases, we are fishing wild populations to extinction, and that's both bad for the environment and bad for us. The Monterey Bay Aquarium website is an excellent resource for information on clean and sustainable seafood sources.

Some of the top recommendations that look as if you can find them just by going to the grocery store:

  • wild Alaskan salmon
  • farmed oysters
  • farmed mussels
  • wild Pacific sardines (packed in olive oil or water, not seed oils!)
  • farmed Rainbow trout
Here is a chart for selecting sustainable alternatives to some poor choices. Health-wise, the above five are all great. For other specific seafoods, I look it up. For instance, domestic farmed channel catfish are environmentally responsible, but are they worth eating? Not to me. Under "Fats and Fatty Acids", we can see that there is more omega-6 than omega-3, so the benefits of the omega-3s are pretty much wiped out. Steamed clams, on the other hand, have more than ten times the omega-3s as omega-6s. They also have good mineral content, tons of real vitamin B12, and exceptional heme iron content.

We typically eat oysters, clams, and wild salmon on a regular basis of about one generous serving per person per week. For instance, we might have raw or steamed oysters one week, homemade clam chowder the next week, and a baked salmon filet the week after that, prepared as follows:

Simple Baked Fish
Good-quality filet(s) of fish, at refrigerator or room temperature
Butter or coconut oil
Seasonings: Fresh lemon juice and pepper are a great combination to start with. There are many great ways to season fish. Rosemary, paprika, mustard, Italian herbs...

Preheat oven to 350°F. Lightly grease the bottom of a glass, stoneware, or enameled baking dish with butter or coconut oil. Place the filet (skin side down, if it has the skin on it) in the dish.

Season as desired. If using lemon and pepper, cut a wedge of lemon and squeeze the juice atop the filet, then sprinkle with black papper. Bake until the middle is just barely done. Start with ten minutes in the oven and check every few minutes after that. The "secret" to cooking fish is to steer clear of overcooking.

Steamed Shellfish
Live clams, mussels, or oysters
Optional: lemon juice, herbs, and/or melted butter for serving

I first steamed fresh clams in my college apartment using a saucepan and a plate. If you think that is low-tech, my grandmother once steamed clams in a coffee maker in a hotel room on vacation! So here is my improvised way to steam shellfish, no special equipment needed:

Clean shellfish under running water. In a large saucepan or medium stockpot, put an inch or so of water over high heat. Arrange shellfish, hinge down, in one layer. Cover to trap steam (using a heat-resistant plate if you do not have a lidded pan). As the water boils, reduce heat to medium. Check every few minutes and remove shellfish as they open - these are done. Tongs are ideal but I have used spoons and an oven mitt.

It is a myth that ones that do not open are bad, so after all the rest are done, any stragglers should be pried open. If they are bad they will smell bad and you will know to throw them out, but I have always found them to be just fine. Many people express concern with shellfish and food poisoning. Always throw away any food that smells bad - our bodies are remarkably attuned to this - so do use common sense, keep things clean, not leave live shellfish sitting in the fridge for days before eating them, etc., but please do not get overly paranoid. To put it into perspective, you are about 47 times as likely to be killed by a medical error while at a hospital or doctor's office than just to get sick at all in a given year from eating shellfish.

What are your favorite ways to eat seafood?

This post is part of Hearth and Soul.


  1. Great post! I love Salmon baked in foil with butter, garlic and lemon! We love all shellfish too.

    I wonder about Wild USA caught Shrimp now though, I read somewhere that after the BP Oil spill, they are no finding shrimp without eyes and all kinds f deformities :/

  2. I like to buy canned salmon (Sea Alaska is the brand I get - it's wild Alaskan salmon and this particular brand doesn't use BPA in their cans), and make salmon patties:

    1 can salmon, 1 egg, ~1/4 c. oats (I've used rolled so far, but I want to give steel-cut a shot next time), whatever seasoning you feel like, and fry them in a skillet. Very easy, cheap, and yay for Omega-3 fatty acids!

  3. Great information and delicious recipes! I think it is great that the Monterey Bay Aquarium website has information on clean and sustainable seafood sources. The first time I took my children there my oldest son asked at every single display, "Would that fish make a good sandwich?" I really wanted to pretend that he belonged to someone else. :)