Fishing for facts

Should we be eating more fish, what fish should we eat and why?

assortment of fish and seafood


The evidence is clear, we need to reduce our meat intake, switching to more plant-based foods. But often this raises some questions about fish as a viable alternative to meat…

● Could we replace some of the meat in our diets with more fish?
● Nutritionally we know fish is up there, but what fish should we be eating?
● Which fish are rich in omega 3 fats
● Can some fish cause toxicity
● …and is fish actually a sustainable alternative?

Tess Warnes is allmanhall’s registered dietitian and works closely with Theo Kuehn, sustainability manager in the team of food procurement experts at allmanhall. Here, together, they take look at some of these issues. A deep-dive into all things fish!

A taster of the nutritional benefits of fish

Fish is nutrient dense, packed full of protein. It also boasts other micronutrients including iodine, selenium, calcium, zinc, Vitamin D and, in some fish, Omega-3 fatty acids. Omega 3 fatty acids are one the main attractions of fish, with it being one of the best sources of this essential nutrient. These fatty acids are thought to have many health benefits including protecting the heart, helping to maintain good memory and supporting the prevention and treatment of depression.

Fish which are especially high in omega 3 fatty acids include:

● salmon
● trout
● mackerel
● herring
● sardines
● crab (fresh)
● whitebait

How much fish should we eat?

The Government advises that we eat two portion of fish per week. One of these should be oily.

oily fish for diet
Age One Portion Size
18 months to three years 1/4 - 3/4 small fillet or one to three tablespoons
Four to six years 1/2 - 1 small fillet or two to four tablespoons
Seven to eleven years 1 - 1 & 1/2 small fillets or four to six tablespoons
12 years to adult 140g (5 oz) fresh fish or one small can oily fish

The most recent National Diet and Nutrition Survey (NDNS) results show that the mean consumption of oily fish was equivalent to 56g per week in adults aged 19 to 64 years and 86g per week in adults aged 65 years and over. This is well below the recommended one portion (140g) per week in all age groups. Mean consumption in children was less than 20g per week.

Are any fish toxic and should some age groups avoid fish?

Oily fish usually has higher levels of pollutants than other types of seafood. For this reason, women who are pregnant or breastfeeding should limit oily fish to no more than 2 portions a week.

Some types of fish (shark, swordfish and marlin) may be high in mercury, so should certainly be avoided if under 16 or pregnant. However, from a sustainability perspective everyone should now try and avoid these fish, as they are becoming endangered.

Is fish a sustainable choice?

Picking up that point, Theo sheds some light on the complicated topic of the sustainability of fish. Here he looks at whether replacing some of the meat in our diets with fish is a sensible and viable option for the planet…

As with the existing production and consumption of a variety of resources and commodities, our current relationship with fish and fishing is detrimental to the planet.

For too long, wild fish populations have been decimated by overfishing, leading to several becoming endangered, from Bluefin Tuna to Atlantic Halibut. When populations of these fish collapse, the reverberations can be felt across the globe, impacting livelihoods, nutrition, and ecosystems.

To meet the increased demand  caused by growing populations and shifting diets, fish farming has more than doubled since 2007. However, this can still be an imperfect solution. Improper management can allow pesticides and feed to leak into the surrounding ecosystems and sadly create breeding grounds for disease and pollution.

Farmed fish also typically have a far higher carbon impact, with farmed prawns leading to almost 30kg of Co2e per Kg of food produced.

The best solution to avoid supporting damaging industries is through education and transparency. Accreditations like the Marine Stewardship Councils Blue Ecolabel, while under some controversy, can be a useful tool. For best practice however, the Marine Conservations Society’s Good Fish Guide is an up-to-date tracker of which fish are best to eat or avoid.

It’s 1-5 rating guide is easy to decipher and clearly indicates which source or species is best to buy, for the planet. For example, wild caught Lobster has a rating of 5. Whereas farmed mussels are best to avoid with a rating of 1.

Roasted Salmon MSC

When produced or caught in an appropriate way, fish has a far lower carbon impact than other animal proteins. Salmon’s carbon impact assessment is 7.63kg of co2e per Kg produced. This is far lower than beef or lamb.

As this decade of action sees a pressing need for us to lower our food related emissions, nutritious and delicious fish are an important resource…

TOP TIPS: How to add more fish to your menu

Some of the blockers to eating more fish include cost and consumer preference or uptake.

Here are a few tips on how to deal with these perceived barriers:

● Tinned fish is generally cheaper than fresh fish
● …and has a longer shelf life so can reduce wastage too
● Mixing stronger tasting oily fish with white fish can help improve uptake of dishes such as fish pie, fish cakes
● Alternating salmon fish fingers with standard fish fingers on the menu can be a good start
● Trying fish in different dishes such as fish tacos, salmon lasagna, fish curry or a teriyaki fish rice bowl is an exciting option
● Experimenting with a themed seafood day gives the chance to test different taster dishes (to see what’s popular)
● … this can support the education of the benefits of eating fish


To summarise and FIN-ish!

Reducing our meat consumption and increasing intake of sustainable fish can have both health and environmental benefits:

● Sustainable fish is a good, nutritious option to include in your diet
● Fish is high in protein, iodine, zinc and some are also high in omega 3, calcium and vitamin D
● Aim for two portions fish per week, one of these being oily fish to provide Omega 3 fatty acids, which is linked to health benefits    ● Tinned fish is cheaper and has a longer shelf life than fresh
● Fish themed days can be used to promote fish with taster dishes to find out what is popular and can include education around the benefits of fish
● Choose your fish carefully, ensure it has a certification such as Marine Stewardship Council (MSC) or Aquaculture Stewardship Council (ASC)
● Check the Marine Conservations Society’s good fish guide for an up to date tracker of which fish to buy

Improving sustainability and nutrition in our diets can absolutely go hand in hand. To understand more or to explore the essential requirement to reduce the ruminants in your menus, do speak to the team at allmanhall.

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