According to new research a diet rich with fruit, vegetables and fish can reduce a child's risk of developing asthma and allergies.
This conclusion was arrived at by scientists in Greece after 400 children on the Spanish island of Menorca were monitored for the first six years of their lives.
The researchers say they believe the study is the first to assess the impact of diet on children's asthma and allergies which also takes into account the food mothers ate during the pregnancy.
The study results showed that the prevalence of asthma and wheezing in children who each day ate more than 40gm of fruit-like vegetables, such as tomatoes, aubergines, cucumbers, green beans and courgettes, was 4.5%, while for those eating fewer vegetables of these types the prevalence rates were around 10%.
The rates of allergies were 13% for those who ate a lot of vegetables and 22% for those with a low intake.
Children who ate more than 60gm of fish a day had asthma and wheezing prevalence rates of 7%; those eating less had rates of around 11%.
It is well known that fruits and vegetables are rich sources of antioxidant chemicals, such as vitamins C and E, selenium and flavonoids and fish is a source of polyunsaturated fats.
Such antioxidants are thought to reduce the inflammation of the airways by protecting the cells there against damage.
For the study the mothers of the 232 boys and 228 girls who had been recruited during antenatal classes, completed questionnaires on their children's health, weight, diet, and breathing problems, every year until their children reached age six-and-a-half.
The researchers from the Department of Social Medicine at the University of Crete, admit the study had limitations as some children had a generally healthier lifestyle.
The researchers say the dietary effects were quite specific and that other fruits and vegetables examined did not provide the same protective effect nor did other food groups included in the study, such as dairy products, meat, poultry and bread.
Dr. Leda Chatzi who led the study says even after adjusting the results for a wide range of variables, the conclusion was that the link between symptom-free children and a diet rich in fruity vegetables and fish was statistically significant.
The findings also reinforce the researchers' earlier findings that a fish-rich diet in pregnancy can help to protect children from asthma and allergies.
The study is published in the current issue of Pediatric Allergy and Immunology.