Metabo Diet Coffee

My coffee is run out. Please remember this important point.
So, i went to Cosmed to purchase Metabo Diet Cofee imported from Japan.
Before buying, i searched on the Internet to see its effects.
Most of people say this kind of coffee is very good for digestation.
won't cause diareha, but can clean up your body.
In addition, Comed is promoting 海綿寶寶. with 8 stamps collection, i can change cute wallet. My old wallet is kind of broken....
Because of so many reasons, i went to buy Metabo Diet Coffee at Cosmed.
This morning, I tried one cup before going to office.
The taste is very smooth. I think people who don't take coffee can accept its flavour very easily. Only black coffee is easy to take. I feel very refreshed before my morning work. Then, I wait...wait for what? toilet la
So far, I have no feeling to go to toilet (strange....).
Could it be diet coffee for everyone, except me?
I hope this kind of nightmare won't happen to me.
Maybe i need another cup tonight....what do you think?
By the way, what's Metabo in Japanese?