I took milk thistle and haven't noticed much, dandelion root appears to be working wonders though.
Know of a good cranberry supplement? No I do not want to eat cranberries every day.
Knudsen makes an unsweetened cranberry juice concentrate that makes a tasty tart spritzer with some mineral water and stevia (or honey, or orange juice concentrate, whatever you like, but the taste benefits greatly from some sort of sweetener). It looks like a tiny bottle, and will set you back $9-10, but it lasts for a really long time.
I've actually had really good luck with every brand of freeze-dried cranberry capsules I've tried, from cheapo to expensive, I think they are kind of hard to screw up. I just grab the cheapest one I can find at Super Supplements, or order from Swanson or Vitacost.
Horsetail tincture is good for the kidneys too if you are finding yourself prone to cystitis or kidney stones. I'm not sure whether it is indicated for general kidney support though.
If you are working on this to get toxins out of your body, I believe extra soluble fiber is recommended for binding to anything that you are asking your body to excrete via the liver before it can be taken back up in the large intestine.
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