Fish can be an important part of a healthy diet. Most fish contain mercury in various amounts and eating fish with high levels of mercury can be harmful to some members of the population. Toronto Public Health’s A Guide to Eating Fish provides clear advice about choosing and eating fish.

Eating a variety of fish is a great way to get the nutrients you, your baby and your children need, such as protein and omega-three fatty acids. These nutrients are important for good health. There are plenty of options you can choose from such as salmon, pollock, and tilapia.

Most fish and shellfish contain small amounts of mercury that is safe to eat. Large fish, such as marlin and shark that live for a long time and eat other fish can contain higher mercury levels. Eating too much fish that are high in mercury can be harmful, especially for:

  • women who could become pregnant
  • pregnant and breastfeeding women
  • children
  • a fetus and baby are the most sensitive to high levels of mercury, which may lead to problems with learning, walking and talking.

Use the information in Toronto Public Health’s A Guide to Eating Fish to choose a variety of fish that are low in mercury to get the most benefits and lower health risks.

Pregnant women, children under five, adults over sixty, and people with a weakened immune system should not eat raw fish or shellfish, including refrigerated smoked fish, sashimi and sushi dishes. Raw or undercooked fish may contain bacteria or parasites that can lead to food poisoning and if you are pregnant, this can affect the baby.

Fish oil supplements should not be considered equivalent to eating fish.

Pregnant individuals should avoid taking fish liver oils, especially if they are already taking a multivitamin supplement containing vitamin A. Excess intake of vitamin A has been linked to birth defects. Talk to your health care provider if you have any questions about this.

The seafood we eat and how we fish or farm matters.  Support sustainable seafood choices to protect wild fish stocks and their homes.

Visit to learn about organizations that provide seafood recommendations for consumers and businesses in Canada. When possible, choose fish products with the Ocean Wise sustainable label.

For more information on making the best environmental fish choices refer to A Guide to Eating Fish.

Toronto Public Health’s A Guide to Eating Fish should be used to help choose fish sold in supermarkets or grocery stores. For more information on safely eating sport fish (fish caught in local lakes and rivers) see The Government of Ontario’s Map: A Guide to Eating Ontario Fish.