Category Archives: TC Luoma

Nutricao e o Peixe de Viveiro

Até que ponto o peixe produzido em viveiro tem o mesmo valor nutritivo? Neste artigo TC Luoma refere o caso específico do salmão e das diferenças de concentração do DHA e EPA entre o salmão do Pacífico (natural) e o salmão do Atlântico (pode ser produzido em viveiro).

“If you’re interested in your health, then you’re no doubt eating salmon, lots of it.

Sure, you’re eating poached salmon for dinner, popping salmon kabobs in-between meals, even thinking about whipping it up in your blender with a couple of scoops of Metabolic Drive.

I mean you’d have to be crazy not to, when you consider all those healthful omega-3 fatty acids that are just oozing out of that slab of delectably pink meat.

Trouble is, you’re probably not really eating the type of salmon you think you are. You’re probably eating something that’s more closely related to a trout, one that’s been dyed to mask its unappetizing gray color. What’s more, that trout has been raised largely on a diet of grain, which negatively affects the amount and variety of omega-3 fatty acids in its meat.

Sucker!

Here’s the thing. There’s obviously a huge market for salmon, but the pesky Pacific salmon, of which there are a number of varieties, can’t be bred in captivity. As such, the season for catching Pacific salmon is pretty much relegated to the months of June and July.

Practically all the Pacific salmon are caught those months, and what isn’t sold immediately is frozen or put into cans.

Because they’re wild, they eat their nature-intended diet, develop their pink or reddish color naturally, and are chock-full of the healthful omega-3 fatty acids we humans covet.

However, the Atlantic salmon – often referred to as “Scottish salmon” so you’ll think they’re wild and cuss a lot – can be bred in captivity. As a result, 99% of the salmon from the Atlantic Ocean are from fish farms where they’re fed a diet of fishmeal and grain.

Because of this diet, the fish are naturally lower in omega-3 fatty acids, and what omega-3 fatty acids they contain will present as ALA, or alpha linolenic acid. Granted, the human body converts ALA to DHA and EPA (the essential fatty acids we prize), but the efficiency rate of this conversion is only between 2 and 15 percent.

Another result of their unnatural diet is their color; the flesh has the grayish hue of old Jockey shorts.

To remedy this fish farmers give the fish astaxanthin and canthaxanthin as artificial colorants. While astaxanthin can be extracted from shrimp flour, it’s generally synthetic. Astaxanthin is a potent antioxidant and often enhances the fish’s fertility and growth, but unfortunately canthaxanthin can accumulate in the human retina and have negative effects.

Another problem posed by captive breeding is disease. Farm-raised Atlantic salmon are plagued by sea lice, tiny parasites that feed on skin, mucus, and blood. As such, fish farmers must resort to chemical remedies that are harmful to sea lice and apparently humans, too.

In 2004, several warnings issued by European scientists advised people to only eat farmed Atlantic salmon every four months or so, lest their liver light up like a prop from the sequel to Tron. A subsequent study published in JAMA gave partial vindication to the beleaguered fish and said that the benefits (protein, reasonable amount of beneficial fatty acids) still outweigh the risks imposed by contaminants, but it still makes you wonder.

So sure, eating “Scottish salmon” is probably better than eating fast-food hamburgers, but it’s not nearly as desirable a food as any of the varieties of Pacific salmon. Of course, you may not be able to readily find Pacific salmon – or afford it – but if you’re like me, you won’t want to harbor any illusions about what you’re eating.

If you want to eat good, healthy salmon, I’d recommend stocking up on canned Pacific salmon and finding a good recipe for salmon patties.”

Original – Aqui