What Not to Eat When You’re Pregnant and Why

It’s widely known that certain dietary changes are recommended during pregnancy. Still, many of us may not be aware of exactly which foods to avoid or the necessity of doing so. 

Why can’t I eat certain foods?

When it comes to foods on the ‘Avoid List’, the main concern is usually their potential for containing the bacteria Listeria monocytogenes and the negative implications it can have for a developing fetus if contracted by a mother during pregnancy. 

As pregnant women are more susceptible to infection due to hormonal changes in the body lowering their immune system, it makes it more challenging for them to fend off disease and infection. Avoiding certain foods altogether and ensuring adequate preparation of others can significantly reduce the risk of Listeria infection during pregnancy.

What exactly is Listeria?

Listeria is a type of bacteria found in some foods which can cause a rare but serious infection called listeriosis. Unlike many other germs, it can enter the bloodstream directly and therefore can get to the baby quickly through the placenta. 

Listeria can be present in many types of foods, but is mainly a problem with the following:

• Unpasteurised milk and other dairy products made from it
• Soft cheeses such as camembert and brie
• Chilled, ready-to-eat foods such as salads, sandwiches, deli meats, cold cuts and pate
• Soft serve ice cream
• Any chilled, pre-prepared foods of which you can’t be sure how long they have been refrigerated post-preparation

It is important to note that these foods do not always contain Listeria. If you have eaten any of these foods at some point during pregnancy and have since experienced no symptoms, you do not need to worry about any further implications for you or your baby. 

The symptoms of Listeria infection include:

• General aches and pains
• Chills
• A fever of 38C and above
• Diarrhoea
• Feeling nauseous and/or vomiting

If you experience these symptoms, particularly after eating any of the foods in the above list, then immediately contact your primary healthcare provider for prompt medical assistance. 

Untreated listeria infection can put your and your baby at increased risk of more severe health complications, including miscarriage, stillbirth, uterine infection and preterm delivery.

Properly wash and cook your food

There are some safer alternatives and ways to prepare food to reduce the risk of listeriosis. These include:

• Freshly cooked meat, fish and seafood ate piping hot and cooked through
• Pasteurised dairy products and hard cheeses
• Freshly washed and prepared vegetables and salads
• Canned foods
• Hard-boiled eggs or yolk well done

The fact that Listeria is quite often present in many types of foods should not be cause for concern. Rest assured that it rarely causes illness. The majority of listeriosis infections are often a result of someone consuming foods with very high levels of bacteria. Avoiding the high-risk foods and ensuring the food you do eat is fresh and well prepared can significantly reduce the incidence of ingesting high levels of Listeria and causing harm to you and your baby.

Other foods to avoid when pregnant

Seafood

Other foods to avoid during pregnancy include swordfish, marlin, shark and raw shellfish. These foods can contain harmful bacteria and viruses that could result in food poisoning. 

Tuna portions should be limited to around 140g per week (equating to 4 medium-sized cans of tuna), and you should eat no more than two portions of oily fish such as salmon, trout or mackerel per week. This is because tuna contains higher amounts of mercury, and oily fish can contain pollutants, both of which can be harmful to an unborn baby.

Caffeine 

It’s also advised to limit caffeine intake during pregnancy. The recommended daily amount is a maximum of 200 milligrams (mg) per day - which is roughly the amount found in 2 cups of instant coffee. High levels of caffeine in pregnancy can result in babies being born at lower weights, which can increase the risk of health issues in later life.

Alcohol

Another consumable to consider limiting during pregnancy is alcohol. Although medical experts are still unsure of how much (if any) alcohol is safe to consume during pregnancy, the main concerns are that babies cannot process alcohol as well as adults. This is because their liver is one of the last organs to develop, usually only maturing in the latter stage of pregnancy. 

With this in mind, the recommendation is to avoid alcohol entirely if you are pregnant or planning for pregnancy, to keep potential risks to the baby to a minimum.

Pregnancy diet plans and help 

The majority of regularly-consumed foods are safe to have in pregnancy, and any dietary changes required can usually be managed relatively easily by most. It is essential during pregnancy, as in all stages of life, to maintain a healthy, varied, and balanced diet as well as proper hydration. You will likely find that you are hungrier than usual. However, there is no need to ‘eat for two’ – it is advised to eat little and often as opposed to just three larger meals a day during pregnancy. 

If you have any specific dietary needs that are affected by the above recommendations or feel that you would like some general information on a pregnancy diet, then it may be worthwhile to meet with a dietician for advice.

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