How does a gastric bypass work?

Does a cloudy day aggravate arthritis? Was the biblical flood real? How does a gastric bypass work? Will a knife in water go blunt? Where do the skeletons on sunken ships go? Why do cats have an extra fold of skin in their ears? And why transmit electricity at high voltage? Dr Chris joins Redi Thlabi for thirty minutes of quickfire Q and A... Like this podcast? Please help us by supporting the Naked Scientists