Mackerel … eat it and add 2.2 years to your life – but don't eat much, it's overfished. Photograph: H Taillard/photocuisine/Corbis
Two stories today further complicate the already vexed issue of eating fish.
The first is the news, if you can call it that, that eating oily fish is good for us. As far as most fish-eaters are concerned this is not an earth-shattering revelation. For years we've known, or have at least been told, that mackerel, herring, sardines and so on are all good stuff. But now it seems that loading up on omega-3s can add 2.2 years to your life, cutting "the overall risk of dying by as much as 27%", however that works.
Second up, and perhaps more significant, is the piscine challenge to the horsemeat scandal, with the discovery that fish counters and chippies are swimming with incorrectly labelled produce, including some fish that hadn't previously entered the food chain.
The connection between the two is that for all the health benefits imparted by fish, eating them is becoming ever more of a headache. Let's take the sainted mackerel, that sustainable, economical, plentiful, omega-3-rich, not to mention delicious specimen. Earlier this year we were told to control our mackerel-eating urges due to over-fishing. Never mind the (disputed) health benefits – mackerel should now be a rare treat.
And a trip to the chippie, once a haddock-or-cod affair, has now been muddled not only by dissenting voices about the ethics of eating cod, but also by the possibility that your simple fish supper consists of a frozen and air-freighted monster of the Mekong.
So where does one begin? Who do we trust?
"Labelling fish accurately is a very difficult thing to do," says fishmonger Robin Moxon. "Every restaurant in town seems to have 'hand-dived' scallops, but I've only ever met two divers. When I get my fish out of Plymouth I know pretty much exactly where it's been fished. But with a new supplier you don't know if it's come from way out at sea, and isn't quite as local as you might have thought."
Perhaps you don't know, but you can, says Calum Richardson at the Bay Fish and Chips in Stonehaven. His chippy has digital menus that display the name and registration of the boat that caught the fish on that particular day. "All the boats have GPS, so every time they drop their nets they log where they were dropped, at what time, the species caught, and how much. When I get a box of fish delivered to the shop I know everything except the fishes' names."
I demolished an exemplary fish supper from Richardson's shop in November (Maimai FR432 was the fishing boat, if you're asking), and was pleased when it was awarded Best Fish and Chips in the UK at this year's Fish and Chips Awards. According to Richardson, six out of 10 of the finalists had bought fish from his supplier in Peterhead.
Just as the horsemeat hoo-ha has been good for proper butchers, so too may news of fishy labelling prove positive for fishmongers. But both also demonstrate the fact that as consumers we can't entirely trust what goes on a label, whether scrawled by hand on a fish counter or printed on a ready meal.
All this confusion – the sustainability or otherwise of certain species, the codliness or otherwise of our fish suppers, Saint Hugh's "misleading and one-sided" Fish Fight – gives weight and urgency to this ongoing problem, and we can be confident that sooner, rather than later, Friday's dinner won't be such an ethical minefield.