The studies are poorly designed, lasting for only a few hours. Long distance runners know.
Opera singers know.
Eighty percent of milk protein is casein, a tenacious glue and allergenic protein. Eat casein and you produce histamines, then mucous. The reaction is often delayed, occurring 12-15 hours after consumption. By eliminating ALL milk and dairy for just one week, most people note the differences, which include better sleep, more energy, better bowel movements, clarity in thought, muscle, bone, and back pain relief.