Fish and shellfish are rich in protein which is helps maintain your muscles, and oily fish are also rich in omega 3 fatty acids, which help to keep your heart healthy. White fish also contain omega 3 oils but in smaller amounts because they tend to be low in fat. Oily fish are also good sources of vitamins A and D.
You can eat the bones as well as the flesh from some fish such as whitebait, canned sardines, pilchards and salmon. Because of this, they're also good sources of calcium and phosphorus.
Shellfish contain similar nutrients to white fish and similar amounts of omega 3. Some shellfish, such as muscles and crab, contain more omega-3 oils, whereas prawns contains very little. Shellfish are also a good source of zinc, needed for wound healing.
Eating fish has many benefits but fish can contain pollutants called dioxins, PCBs (polychlorinated biphenyls) and mercury. Although these pollutants have no immediate effect, they can cause problems later as they build up in the body over time.
This shouldn't make you feel worried about eating oily fish - the benefits far outweigh the risks, as long as you don't exceed the recommended maximum.
Oily and white fish
Some types of oily fish:
Salmon
Trout
Mackerel
Herring
Sardines
Pilchards
Kipper
Eel
Whitebait
Tuna (fresh only, not canned)
Anchovies
Swordfish
Bloater
Cacha
Carp
Hilsa
Jack fish
Katla
Orange roughy
Pangas
Sprats
Some types of white fish:
Cod
Haddock
Plaice
Coley
Whiting
Lemon sole
Skate
Halibut
Rock salmon/Dogfish
Ayr
Catfish
Dover sole
Flounder
Flying fish
Hake
Hoki
John Dory
Kalabasu
Ling
Monkfish
Parrot fish
Pollack
Pomfret
Red and grey mullet
Red fish
Red snapper
Rohu
Sea bass
Sea bream
Shark
Tilapia
Turbot
Tinned tuna
Marlin
Recommendations
Current recommendations say we should eat two portions of fish a week, one of which is an oily fish.
The recommended maximum intakes of oily fish are:
Two portions of oily fish (a portion is about 140g) a week, for
- Girls and women who are trying for a baby or may try for a baby in the future
- Women who are pregnant or beastfeeding
Four portions of oily fish a week, for
This upper limit is in place because of the pollutants which may be in fish. The limits for girls and women who may have children in the future and pregnant women are more restrictive, to prevent ill effects on foetal development. Even though women who are planning for a baby or who are pregnant should eat less, the omega-3 oils are very important for helping a baby's nervous system to develop, so you should still try to eat up to two portions of oily fish a week.
People who eat shark, swordfish or marlin shouldn't eat more than one portion a week. Women who are trying for a baby or are pregnant shouldn't eat them at all because these fish contain higher levels of mercury, which can be harmful if the levels build up too much in the body.
Healthy ways to cook fish
Fish grilled, poached or baked is much healthier than frying it in fat.
Fish and chips are fine as an occasional treat, but there are ways to make them healthier:
- Have peas or reduced salt and sugar baked beans on the side
- Share a portion of chips with someone else and have a bread roll on the side if you need extra
- Don't ask the fish and chip shop to add salt - put it on yourself so you use less
- Use thicker chips because they absorb less fat during cooking than thin cut chips
Eating fish safely
Some shellfish are ‘filter feeders', which means that they feed off the water which passes through them and could be polluted. These shellfish and others can contain bacteria and viruses, so it's important to cook them thoroughly to kill the bugs. Some shellfish which are eaten raw - for example, oysters - may still contain bacteria and viruses, so pregnant women, elderly people and people who are unwell are advised to avoid eating raw shellfish to reduce their risk of suffering from food poisoning.
Buying sustainable fish
Fish are a healthy part of our diet and most of us should be aiming to eat more; however, when you buy fish it's worth considering how you can help protect the environment as well as your health.
Marine stocks around the world are becoming depleted because of increasing demands for fish. Sustainable fishing ensures there is minimal negative impact on the marine environment and fish stocks. So, if you buy fish from sustainable sources you are helping to protect the environment, now and in the future.