The age-old belief that milk consumption boosts the production of phlegm and exacerbates respiratory conditions such as asthma and common cold has been debunked as a myth by a paediatric expert.
Dr. Ian Balfour-Lynn, a children's respiratory consultant at the London’s Royal Brompton Hospital said that there is absolutely no need to avoid milk in children with asthma, cystic fibrosis, or respiratory infections.
The origin of the myth dates back to as long as the 13th century, and was further perpetuated by children’s health guru, Dr. Spock in his book on baby and child care published in 1948. However, there hasn't been any robust clinical evidence to corroborate this claim.
Although there is evidence that a protein by-product of milk breakdown could possibly influence a gene that stimulates mucus production, it is known to happen in the bowel and it is highly unlikely that the respiratory system may be involved. The possible explanation for this myth lies in how milk feels in the mouth. Salivary compounds interact with the milk which is an emulsion and boost its volume, thereby creating a perception of mucus.
Writing in the Archives of Disease in Childhood, Dr. Balfour-Lynn says that being a key source of energy, calcium and vitamins, milk should not be avoided in children. Conditions such as cystic fibrosis or asthma are often treated with large doses of steroids which take a toll on bone health. Milk is, therefore, more essential in such children to boost their bone health.
