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.
Ford, Volkswagen and Porsche, for example, recommend oil changes every 10,000 miles. So does Toyota on several engines, including the Prius' 1.8-liter four-cylinder and the Camry's 2.5-liter four-cylinder. BMW says owners can go up to 15,000 miles between oil changes (with synthetic oil). The intervals vary by manufacturer and engines, so consult your owner's manual or maintenance schedule to see how often to change the oil in your vehicle and what type of oil to use. You may be surprised.