A recent study found that pregnant women taking 400 mg of docosahexaenoic acid (DHA), an omega-3 fat, helped their newborns to fight off cold symptoms. Symptoms that were reduced included coughing, nasal congestion and runny noses.
The cold-fighting effect of the DHA lasted for six months, and even after that the children’s cold symptoms tended not to last as long as those of other children.
Time Magazine reports:
“What does the mother's diet have to do with her child's ability to fend off colds? A developing baby's immune system relies on cues it receives from its environment -- in this case the womb -- to start building a cellular defense system that can recognize friendly tissue from foreign ones such as bacteria and viruses. Much of this early arsenal comes from information from the mother, but exactly how this data is translated from mom to baby isn't clear yet.”