Allergy prevention

Although there is no sure way of preventing a child from developing an allergy, certain things can be done that help reduce the risk.

A smiling toddler gets a spoonful of porridge

To date, we still do not understand all the circumstances that give rise to allergies and what counteracts allergies. However, the latest research does enable us to derive important and useful recommendations for allergy prevention in everyday life.

Hereditary predisposition

Everyone gets half of their genetic characteristics from their mother and father. These genes have an influence on eye or hair colour, but also on the risk of certain illnesses, such as allergies. Whether someone later actually develops an allergy depends on other factors.

The causes of the increasing number of allergy sufferers are currently the subject of intensive research. The following insights have already been gained in respect of allergy prevention.

Mother’s diet

A healthy, balanced diet during pregnancy and breast-feeding is important for the mother-to-be and her child. If a mother has no food allergies or intolerances, she does not have to stick to a diet; leaving out specific foods cannot prevent allergies from developing in the child.

Birth methods

Studies have established that children delivered by Caesarean section have an increased risk of allergy compared to those delivered naturally.


If possible, the child should be exclusively breast-fed, at least during the first four months of life. If partial/full breast-feeding is not possible, an infant formula in a baby bottle is an appropriate alternative. There are hydrolysed formulas for children at risk for allergies - i.e. the parents or older siblings already have an allergy . But it remains unclear to what extent use of these formulas helps prevent allergies. Cow’s milk or milk from other mammals and vegetable drinks, such as soya and rice, are not suitable as a substitute for mother’s milk or baby milk in the first 12 months of life.

Baby’s diet

From five months, the gradual introduction of baby foods in addition to breast-feeding is advised, bearing in mind the applicable recommendations ( Introducing the child to as wide a variety of food as possible is thought to lower the risk of allergy and asthma.

Infant’s diet

From the second year of life, children can eat the same food as offered to the whole family. From then on, they can tolerate larger quantities of yoghurt and milk as well as cheese and curd. Exception: whole nuts and peanuts should not be given until the third year of life because of the risk of suffocation. However, if these nuts are contained or processed in other foods, the child may eat them.

Vitamin D

Vitamin D is important for healthy teeth and bones. The amount taken in food is small and even that produced by the body itself from sunlight is usually insufficient. Giving babies and infants vitamin D in the form of drops is therefore clearly recommended. There is also evidence that vitamin D might help protect against the development of allergies, but to date the study results are conflicting.


If the mother smokes during pregnancy or is exposed to passive smoke, this will increase the allergy risk for the unborn child. The risk is additionally increased if the child continues to be surrounded by passive smoke after birth. This is why both mother and father should quit smoking during and after the pregnancy. The child should grow up in a smoke-free environment.


It is debatable what effect pets have on the development of allergies. It is assumed that for children and adults without an increased risk of allergy there is no reason not to have household pets.

Indoor pollutants

There is evidence that indoor air pollutants, such as formaldehyde or volatile organic compounds (VOC), increase the risk of allergies, especially asthma. It is therefore important to ensure that the products you use at home, such as adhesives, fabrics and paints, are low in pollutants.

Mould and humidity

A child’s risk of allergies and asthma increases with exposure to mould and high humidity. In order to prevent excessive humidity and hence the risk of mould growth, it is imperative to ensure living and working spaces are aired properly and regularly: air them thoroughly (allowing a through-draught) for 5 to 10 minutes twice to 3 times a day. Relative air humidity should not exceed 50 per cent.


Numerous studies have shown that allergy risk is not increased by vaccinations. It is therefore advisable for all children – including those with an atopic tendency or those who already have allergies – to receive the basic vaccinations according to the Swiss vaccination schedule.


Current scientific findings show that a healthy bodyweight helps reduce the risk of severe asthma. It is therefore important to avoid being overweight during infancy and early childhood.

Career choice

Not all occupations are equally suitable for young people with allergies or known sensitisation. It is therefore important to take this into consideration when choosing a career. GPs, allergy specialists and other professionals can help clarify your particular situation in this regard.

Editors: aha! Swiss Allergy Centre in co-operation with the Scientific Advisory Board.