Next time you eat fish, order a plate of kavall (mackerel) instead of swordfish because it is not only cheaper but richer in healthy omega oils, experts argue.

And for the environmentally conscious, the little fish is also more sustainable.

The healthiest fish are those high in omega fish oils, such as kavall, sawrell (horse mackerel) and salmon, according to Stanley Farrugia Randon, a doctor.

These oils increase the high density lipoprotein in the blood, which decreases the risk of heart attacks and strokes.

But there was also an environmental consideration to stop eating swordfish, he added, since it was not being caught sustainably. Swordfish are captured young to keep up with demand.

Dr Farrugia Randon, from Din l-Art Ħelwa, is a member of the green fishing coalition Fish4tomorrow, which aims to raise awareness on the sustainability of seafood.

Nutritionist and occupational therapist Daniela Cassola said fish such as mackerel and salmon were important for pregnancy and breastfeeding since they could help the development of the baby’s nervous system.

Dr Cassola, meanwhile, noted that environmental contaminants, such as mercury, were higher in large predators like swordfish.

This was reiterated by John Daniel Farrugia, who heads Fish4tomorrow. He noted that fish which was lower down the food chain, such as kavall, vopi (bogue) or kaħli (saddled sea bream) tended to have a lower concentration of pollutants. On the other hand, top predators like swordfish and tuna absorb pollutants all the way up the food chain.

Tuna was also known to have higher levels of methyl mercury and it was not uncommon for people to require treatment after eating it, Mr Farrugia said.

A lot of the fish we’re promoting as sustainable are generally cheaper because there isn’t high demand for them

Still, people often opt for swordfish and tuna steaks which come without the kavall’s annoying little bones. This has resulted in a staggering difference in their sale price.

When this newspaper went to print, the price of sawrell and kavall varied between €3 and €4 per kilo, while that of swordfish and tuna stood between €12 and €14 per kilo.

“A lot of the fish we’re promoting as sustainable are generally cheaper because there isn’t high demand for them. Fishing efforts are focused on a few popular fish, contributing to their decline,” Mr Farrugia noted.

Fish4tomorrow have an online guide based on the environ­mental sustainability of fish consumed locally.

Tuna, dusky grouper (ċerna) and dentex (denċi) are among the fish in their “avoid list”. These types of fish generally reproduce slower than some of the smaller fish, so high fishing efforts have been detrimental to the health of their stocks.

For information on fish sustainability: http://fish4tomorrow.com/

Deboning

Carmen Chetcuti’s tips to debone a kavall:

• Place the gutted fish on its side.

• Using a filleting knife, slit the belly from behind the gills to the tail fin.

• Turn the fish over, flesh-side down, dorsal fin up.

• Press hard along the backbone to loosen it from the flesh.

• Turn the fish over, get hold of the backbone at the head and ease it away slowly.