In recent decades, it has become increasingly clear that genetics itself does not explain the risk of developing allergies. Obviously, environmental factors, including exposure to the environment before and during birth, play a role. You can program an increased or decreased risk of allergies.
Prenatal growth and allergy risk
Can birth weight be an indicator of the risk of developing childhood allergies, Australian researchers have sought to investigate. Exploring whether prenatal growth affects allergy susceptibility, in 1869 they reviewed the studies from which they selected and analyzed 42.
Increase your risk by weighing more on your child's scale
An increase in birth weight of 1 kg was associated with a 44% higher risk of childhood food allergy (odds ratio (OR): 1.44, 95% CI: 1.04 – 1.99, p = 0.001).
Similarly, the risk of allergic dermatitis in the further life of the child is increased by 17% if the kilogram is heavier than the control group (OR: 1.17, 95% CI: 1.04 – 1.32, p = 0.008).
The risk of dermatitis is increased by one-third
The risk of allergic dermatitis is even higher when we consider the first two years of life: If a child weighs 3.5 kg, the risk of developing allergic dermatitis is 34% higher than children born 2.5 kg (OR: 1.34, 95 % CI: 1.08 – 1.68, p = 0.009).
There was no association with birth weight in relation to the risk of allergic rhinitis.
Does low fetal growth protect against allergies?
In contrast, these results suggest that limited fetal growth could protect against some allergic diseases, according to Australian scientists.