Pregnancy nutrition and your baby’s immune system

Pregnancy nutrition and your baby’s immune system

Pregnant woman cutting an apple

Experts now believe that nutrition during pregnancy is likely to influence an unborn baby’s developing immune system. It is recognised that good nutrition during pregnancy may reduce a child’s risk of developing an allergy later in life.

The importance of supporting a developing immune system

The primary role of the immune system is to defend against infections and protect the body’s own cells. The immune system is a vast network throughout the body, with the majority of the immune system existing in the gut.

In cases of allergy the immune system isn’t working as it should: the immune system overreacts to an allergen (such as a food, drug or insect bite) and causes an allergic response such as hives, eczema, asthma or in severe cases, anaphylaxis.

Experts now understand some of the influence that nutrition can have on the developing immune system and what you can do during pregnancy to strengthen your child’s immune function and reduce the risk of developing an allergy later in life.

Pregnancy nutrition and reducing risk of allergies

Experts recommend that following a non-restrictive pregnancy diet with a focus on Omega-3 DHA, vitamin D and foods that help to build a diverse gut flora, may reduce the risk of a child developing allergies later in life.

A non–restrictive diet

It’s important to include nuts, nut butter, fish and eggs in your pregnancy diet. Unless you’re allergic yourself, then there is no need to exclude these foods. A non-restrictive diet during pregnancy is important to ensure you and your baby are getting enough energy, vitamins and minerals.


Make sure your pregnancy diet includes long chain polyunsaturated Omega-3 docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). Oily fish such as mackerel and salmon are good sources. Include 2-3 portions per week during pregnancy and breastfeeding as there is some evidence that this may help to prevent eczema in early life. Other sources of Omega-3 DHA include nuts and seeds.

Vitamin D – getting enough sunlight

Evidence suggests that a lack of vitamin D in pregnancy may be associated with higher prevalence of allergies. Getting the right amount of vitamin D from natural sources can be difficult – it is only available from a few foods and mostly produced in response to sunlight. It’s important if you have limited exposure to sunlight, wear a veil or have dark skin, that you speak to your healthcare professional about getting your vitamin D levels tested.

Build a diverse gut flora

80% of the immune system lies within the gut, therefore building a healthy gut flora will help to support the immune system. To build a healthy gut flora, include probiotics in your diet, such as probiotic-containing yoghurts. Probiotics are good bacteria and will help to build a healthy gut flora.  Prebiotics are also important. They are food for the probiotics and will help the good bacteria continue to grow in your gut. Some good sources of prebiotics include kiwi fruit, bananas and asparagus.

Read more from our experts

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