When you have symptoms (belly pain, diarrhea, a lot of gas), choose foods that are easy on your gut. The trick to managing the disease is to choose foods from the left hand column when you have a flare up or an upset in the functioning of your gut. These foods are low in fiber, fats and are easier on you.
Copper pipes corrode as well, but (theoretically) over a longer period than the galvanized types. Generally a copper pipe can last 50-70 years under good conditions. PH levels in the water and grounding both affect the pipes and speed up corrosion extensively.
Cast Iron: The NACHI chart rates cast iron waste pipe at from 50 to 60 years, though it can last longer -- the NAHB says cast-iron systems can last up to 100 years, but there is a lot of anecdotal information from plumbers about cast iron being ruined in under 40 years. Cast iron will rust from the inside out.