Pregnancy increases the risk of food poisoning, and there are certain foods pregnant women should avoid because of the risk of bacteria such as listeria. Symptoms associated with food poisoning, including diarrhoea, vomiting, nausea, abdominal pains and fever are unpleasant at the best of times, particularly so when a woman is pregnant. Some infections and types of food poisoning are also potentially damaging to an unborn baby’s development.
Substances Harmful to Women When They are Pregnant
Pregnant women should be aware that potentially harmful substances including bacteria, parasites, mercury, pollutants and vitamin A, can be present in certain foods. Following is a list of substances to avoid during pregnancy:
- Listeria - Listeria is a bacteria which can lead to listeriosis. Although rare, listeriosis is a dangerous infection with flu-like symptoms which can affect newborn babies, and lead to miscarriage and stillbirth.
- Salmonella - Although unlikely to harm an unborn baby, salmonella is a bacteria which causes food poisoning.
- Campylobacter - Campylobacter bacteria causes food poisoning and may lead to miscarriage and premature birth.
- Toxoplasmosis - Toxoplasmosis infection is rare, but the toxoplasmosis parasite can harm an unborn baby.
- Mercury - A high intake of mercury may be harmful to the development of an unborn baby’s nervous system.
- Pollutants - Chemical pollutants such as dioxins and PCBs can harm a developing baby.
- Vitamin A - Vitamin A is a fat soluble vitamin that can build to high levels in the body and become toxic to an unborn baby, causing birth defects.
Which Foods Should Women Avoid During Pregnancy?
Here is a list of foods that women should avoid eating, or minimise, if they are pregnant:
- Cheese - Camembert, brie and other unpasteurised soft cheeses, as well as blue-veined cheeses such as stilton, can contain listeria. Unpasteurised dairy products can also contain salmonella and campylobacter bacteria. Unpasteurised goats’ cheese may contain the toxoplasmosis parasite.
- Liver - Large amounts of liver or foods containing liver such as pâté should be avoided, as they are high in vitamin A. Care needs to be taken with supplements and fish oils, such as cod liver oil, as these also contain vitamin A.
- Raw Eggs - Raw eggs and products that contain raw or partially cooked egg, such as homemade mayonnaise and hollandaise sauce, may contain salmonella. The white and the yolk of eggs should be fully cooked and solid before eating.
- Fish - While most types of fish can be enjoyed during pregnancy, swordfish, marlin, king mackerel, tilefish and shark should not be eaten as they may contain high levels of mercury. Tuna has also been found to contain mercury, therefore no more than four medium-sized tins or two tuna steaks should be consumed each week. Oily fish such as salmon, herring, trout, sardines, fresh tuna and mackerel can contain dioxins, PCBs and other pollutants, and should be limited to no more than two portions per week. All seafood, including shellfish, must be thoroughly cooked before eating, and chilled smoked seafood is best avoided.
- Undercooked Meat - Meat or poultry that is raw or partially cooked can contain campylobacter and salmonella bacteria. Particular attention should be paid to poultry and minced meat, such as sausages, which must be steaming hot (about 75°C) throughout before eating and contain no pink flesh. Undercooked meat can also contain the toxoplasmosis parasite, as can cured meats such as salami and Parma ham.
- Pâté - All types of chilled pâté, vegetable as well as meat, can contain listeria.
- Prepared Salads - Some prepared salads, such as potato salad and coleslaw may contain listeria.
- Under-Heated Ready Meals - Ready meals must be heated all the way through, until they are piping hot, or there may be a risk of listeria.
- Unwashed Fruit and Vegetables - Soil left on unwashed fruits and vegetables may contain the toxoplasmosis parasite. Bacteria can also be found on raw sprouts such as mung beans and alfalfa, and so these are best avoided.
An understanding of which foods to avoid during pregnancy, along with knowledge of good food hygiene practices, can help to protect the health of the mother and her unborn baby. For more information about health during pregnancy, read Drinks Women Should Avoid During Pregnancy, How to Avoid Listeria Infection During Pregnancy and Why is Folic Acid Important During Pregnancy?
Food choices when planning a pregnancy are also important. For more information, read Foods to Increase Fertility.
Resources:
- Food Standards Agency. “When You’re Pregnant.” (Accessed 24th November 2009)
- Mayo Clinic. “Pregnancy Nutrition: Foods to Avoid During Pregnancy.” (Accessed 24th November 2009)
- NHS Choices. “Which Foods Should I Avoid During Pregnancy?’ (Accessed 24th November 2009)
Sharon Kirby - Sharon is a freelance health writer and contributes to various print and online publications. Writing credits include Nursing Times, Good ...
