Hi Mona! Those are some very valid questions you (and your husband) have asked!
Here are some interesting links:
What are Gallstones?
*if your bile ducts are blocked by stones then your liver and gallbladder aren't functioning properly...an obvious sign of this is the feeling of abdominal fullness after eating and discomfort in that area.
Some causes of gallstones?
Stagnant bile which forms into these stones. Why does one have stagnant bile? Lack of water, fear, stress, lack of nutrition and assimilation of nutrients (clogged & toxic intestines) The list goes on and on. Check out Agnes post...
This is a pretty fascinating page filled with information (the FAQ's):
Unless your husband feels super fantastically healthy, he could probably use some liver flushes! People who don't have gallbladder attacks report food and chemical allergies going away, more energy, a heightened sense of well-being...the list goes on.
I hope your husband decides to try it out with you!