"The season a person is born in influences a wide range of things: from risk of allergic disease, to height and lifespan. Yet little is known about how a one-time exposure like the season of birth has such lasting effects."
This was said by researchers at the University of Southampton and although they don't have complete answers, they are one step closer to understanding how one's season of birth is linked to risks of allergy later in life.
Finnish scientists tested about 1000 children born between 2001 and 2006 in southeast Finland for sensitisation to food allergens up to the age of 4.
Results showed that the children that ended their first three months of development during April and May, were three times more likely to become allergic to milk and eggs than kids in the same stage of development in the winter. And those born in fall or winter have higher levels of antibodies to allergies than babies born in the summer. This could be because of the timing of the baby’s first chest infection as colds tend to be more common in winter and therefore more antibodies are produced, or because of the levels of allergens such as pollen and house dust mite which vary by season.
Other theories include seasonal variations in sunlight, which could affect vitamin D levels, and maternal diet as price and availability of fruit and vegetables vary by season.
The study is published online in the Journal of Epidemiology and Community Health.