Instead: Hydrate with H2O. One of the best measures you can take to avoid kidney stones is to drink plenty of water, leading you to urinate a lot. So, be sure to keep well hydrated, especially when engaging in exercise or activities that cause a lot of sweating. It's Not Just the Oxalate.
You didn't say what year or model BMW. The service intervals vary a huge amount between models a years. BMW built since the mid-1980s have a service indicator. You should change the oil when the service indicator tells you to. On BMWs that specify synthetic oil, you should change the oil when the indicator counts down to zero or once a year whichever comes first.
Changing the oil isn't just a pesky chore--it's a necessity if you want your vehicle to last. Changing your oil with regularity can prolong the life of your engine and save you a lot of money and headaches over time. The bottom line: Buying oil is cheaper than replacing an engine. So how often should you change your oil? Knowing when to change your oil is tricky because there isn't a one-size-fits-all solution. Different cars and engines require different maintenance schedules. The old rule-of-thumb required that you change your oil between every 1,000 to 3,000 miles. This rule was black and white--about as basic as any rule of the road--and was drilled into drivers. But times have changed.