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What is Which of the following is not true about Rumination disorder ? and explain in detail?
Rumination disorder (Rumination syndrome) 

Rumination disorder is a lesser known form of disordered eating.
Rumination disorder typically develops in infant below the age of one year. Rumination disorder can also be diagnosed in older individuals including children, adolescents and adults.
It involves effortless regurgitation of swallowed or partially digested food.
There is no retching, nausea, odor or abdominal pain associated with this condition like there is with typical vomiting.
Although spontaneous remissions are common, severe secondary complications can develop, such as progressive malnutrition, dehydration, and lower resistance to infections.
Failure to thrive, with absence of growth and development delays in all areas, can occur.