There is no current consensus among biologists on the questions of how sex in Eukaryotes arose in evolution, what basic function sexual reproduction serves, and why it is maintained, given the basic two-fold cost of sex.
Excessive production of gas by bacteria is a common cause of intermittent abdominal bloating/distention. Bacteria can produce too much gas in three ways. First, the amount of gas that bacteria produce varies from individual to individual.
Dehydration: Excessive loss of body water. Diseases of the gastrointestinal tract that cause vomiting or diarrhea may lead to dehydration. There are a number of other causes of dehydration including heat exposure, prolonged vigorous exercise, kidney disease, and medications that cause voiding (diuretics). One clue to dehydration is a rapid drop in weight. A loss of over 10% (15 pounds in a person weighing 150 pounds) is considered severe.