Preventing Allergies with Probiotics

Exposing pregnant mothers and infants to probiotic bacteria could help stimulate the growth of the immune system and play a role in preventing allergies, according to researchers at the University of Helsinki.

The team selected 1,223 women who either had a history of allergies or whose partners did, or both. Since susceptibility to allergy is partly genetic, they assumed the babies were predisposed to allergies. The women were given probiotic or placebo doses daily from the eighth month of pregnancy to six months after birth. At three, six and 24 months, pediatricians examined the children without knowing whether they were probiotic- or placebo-treated babies.

The researchers found that levels of key proteins associated with tissue inflammation were 50 percent higher on average in the blood of probiotic-treated infants than in the blood of placebo-treated infants. Inflammation is thought to stimulate the immune system, and so reduce allergic reaction. Probiotic children also were 30 percent less likely than their untreated counterparts to develop an itchy skin condition known as atopic eczema, which is often an early manifestation of allergies.

The findings support the idea that allergies have increased, at least partially, because of the deficit of bacteria in modern living. Historically, food was loaded with bacteria and caused chronic immune responses that resulted in inflammation. In the absence of such heavy bacterial exposure, the immune system is much less active than it should be and this leads to malfunction and can lead to allergies.