Research and its results
Researchers surveyed nearly 2.1 people with eczema, 70,000 people with various types of food allergies, and 100,000 people with hay fever. All of these are allergic conditions - eczema is also known as atopic dermatitis, and hay fever is also known as allergic rhinitis. The data comes from more than 15,000 studies, mostly from Europe. However, between 30% and 40% of the global population suffer from this type of allergy as well as asthma and anaphylaxis.
They examined whether a baby's weight at birth was associated with the risk of future allergies in children, even after adjusting for the baby's gestational weight at birth. They found a significant increase in risk that was not seen for babies born abnormally small for their gestational age. Therefore, these children appear to have immune systems that are resistant to allergic reactions, but severe growth restriction is associated with a higher risk of other diseases later in life, some of which are congenital and some of which are acquired.
early research
The findings are consistent with previous research showing that newborns with high birth weight have an increased risk of emergency visits for asthma, compared with those in the normal weight range. For every 100 grams of weight above 4.5 kilograms (the upper limit of normal birth weight), the risk of an emergency visit for asthma increases by 10 percent. Earlier research also pointed to low-income status, male gender and Aboriginal ancestry as risk factors.
Various mechanisms that may increase the risk of asthma in children include deterioration of lung function due to reduced airflow velocity during expiration and an increased tendency of small lung airways to close when the pressure within the small lung airways decreases. maturity. These children also have weaker respiratory muscle activity.
Obesity also increases inflammation throughout the body and may release molecules that cause airway inflammation. Fat cells may also cause mast cell activation, which is directly related to airway smooth muscle spasm.
Impact and future directions
Childhood allergies don't necessarily go away with age; sometimes they do and sometimes they don't. Problems like egg allergies outgrow many children, whereas peanut allergies are more likely to persist. Because there is so little research in this area, some persistent allergies that occur even in adults may go undetected.
It is becoming increasingly clear that genetics alone do not explain the risk of allergies and that environmental exposures before and around birth can make an individual more or less at risk for allergies. Therefore, mothers of older infants should know how to change the conditions at home to protect their children from allergies. The answer lies not in making sure babies have growth restriction, but in understanding how this condition can help prevent allergies.
Most of the studies reviewed were conducted in young children. The researchers note that it is necessary to conduct these investigations in older age groups, such as older children, adolescents, and adults, to understand how and when lowering birth weight works to improve immunity and reduce the risk of allergies. tendency. They also wanted to know whether the relationship would taper off after a few years or remain active over time.
