Apple cider vinegar is effective in preventing oxidative stress of the kidneys. It increases the levels of antioxidants in the body, balances blood sugar levels and reduces blood pressure, creating optimum conditions for kidney health. Apple cider vinegar contains citric acid which dissolves kidney stones. Frequent intake of apple cider vinegar also flushes out toxins from the kidneys.Kidney beans not only resemble the kidneys but also remove waste and toxins from the kidney and flush out kidney stones effectively. Kidney beans are rich in Vitamin B, fiber and several minerals which help to clean the kidney and boost the function of the urinary tract.Another effective cleansing agent for the kidneys is cranberry juice which supports the urinary tract, fights urinary tract infections and removes excess calcium oxalate. Beets and their juices contain Betaine which increases urine acidity, prevents build-up of struvite and calcium phosphate and reduces the chances of kidney stone formation. Other effective cleansing agents are coconut water, cucumber juice and cherries. For more information on preventing and treating kidney problems, visit the site, Advanced Urology Institute.