The truth about fish
Large oily fish such as swordfish, shark, tuna and salmon contain more toxic heavy metals than smaller fish, and should be eaten sparingly by sensitive individuals: women of childbearing age, pregnant women, breast feeding women, babies and young children, those with weakened immune function or very sick people.
Through human pollution such as plastics, oil, toxic chemicals like pesticides and industrial waste Sea Water has become polluted with heavy metals such as mercury, arsenic and cadmium which are toxic to humans. These fat soluble metals (especially mercury) are readily absorbed by fish and stored in their fat tissues through which accumulates throughout their lifetime. Larger oily fish accumulate more heavy metals than smaller oily fish as they are higher up in the food chain, meaning they consume already contaminated smaller fish. On consumption of the oily fish, the heavy metals can be stored in human fat cells and can transfer to the baby in pregnant women which can have detrimental effects on its developing nervous system. Oily fish is still important for good health and should still be incorporated into the diet, smaller oily fish such as wild mackerel and sardines are the best choices as they accumulate less heavy metals within their fat tissue. White fish have a low fat content therefore can be eaten with less caution due to the lower storage of fat soluble heavy metals. Fat in white fish is stored in the liver; therefore this is where the fat-soluble heavy metals are stored. Cod liver oil should be avoided; a better source of omega 3 fats would be from purified fish oil, or omega 3 EPA supplements. The best plant source and a good alternative is Flax oil.