British researchers have found that avoiding certain foods and dust mites during our first months of life may help prevent asthma. Professor Syed Hasan Arshad and colleages from the David Hide Asthma and Allergy Centre, Isle of Wight, England have been tracking 120 children since 1990 in the Isle of Wight Primary Prevention Study. The children – having two or more family members had an allergic disorder – were considered to be at high risk of developing allergic disease on the basis.

Professor Arshad said:

The 58 infants up to one year old and their mothers in the prevention group followed a diet that avoided dairy products, soya and nuts. We checked their compliance by randomly testing breast milk.

The infants were also given vinyl mattresses and covers, and acracide was used to reduce the level of house dust mite. The mothers of the 62 infants in the control group did not make these changes to their diet and bedding.

The results of the 18-year follow-up of the children were presented at the congress of the European Academy of Allergy and Clinical Immunology by Dr. Martha Scott, who had conducted the follow-up.

The researchers found that at one, two, four and eight years old, there was a consistent reduction in atopy (an immediate allergic reaction) in those children in the prevention group. At the age of 18 years, there was considerably less asthma in the prevention group compared to the control group. A further analysis of allergic and non-allergic asthma found lower rates of allergic asthma in the prevention group.

Research carried out previously had shown the complexity of asthma and the importance of the interaction between genetic and environmental factors particularly, but not exclusively, in the early years of life. Atopy is arguably the most significant genetic risk factor for asthma. Despite intensive efforts to develop new treatments, asthma is still an incurable disease.

Evidence of changes in the child’s airways consistent with asthma indicates that early intervention during early infancy (within the first few months of life) is likely to be key in preventing the remodelling of airways which is the main characteristic of asthma.

Dr. Scott said:

Whilst this study is small it does suggest that it is possible to prevent the onset of asthma in high-risk individuals by instituting a strict regime that avoids some of the common triggers for asthma in the first year of life. We have shown that the beneficial effect lasts for many years

This study is important as a proof of the concept that environmental manipulation in early life lowers the prevalence of asthma in high risk people.

The researchers say a further, larger-scale study to identify who is most likely to benefit from this type of intervention strategy is required.

Source: The European Academy of Allergy and Clinical Immunology