The milk mucus belief: sensations associated with the belief and characteristics of believers.

The belief that milk produces mucus is widespread in the community and is associated with a significant reduction in milk consumption. Sensations associated with milk drinking were reported by otherwise healthy believers and non-believers in the milk-mucus effect (N = 169) in an unstructured interview, with further responses prompted about the duration, type and amount of milk causing the effect. The site predominantly affected was the throat, with sensations related to difficulty in swallowing and perceived thickness of mucus and salivary secretions, rather than excessive mucus production. The effect required only a small amount of milk and was reported to be of short duration. The chronic respiratory symptom history and dairy product intake of 130 of these subjects were also assessed. Milk-mucus believers were different from non-believers, reporting more respiratory symptoms and consuming less milk and dairy products. Symptoms consistent with the known effects of food allergy or intolerance were not reported.