Blood is mostly made up of water, as are our organs and muscles. To read specifically about edema, swelling caused by fluid retention where excess fluid is trapped in the body's tissues, see our article Edema: Causes, Symptoms and Treatments.
If you use the Amsoil Ea15K01 and the ASM oil (For 3rd gen Prius), then you can safely go 15,000 miles between oil changes. I drive 25,000 miles per year in my Prius. Amsoil backs up their products by a written warranty.
Answer Wiki. According to the manual, Toyota 2011 Prius Warranty and Maintenance Guide, your 2011 Toyota Prius requires an engine oil and filter change every 10,000 miles, if using 0W-20 synthetic oil, or every 5,000 miles if using anything else. If I were interested in keeping my warranty in force, I would stick with the manual's recommendations.