Do what god intended you to do and drink only WATER and the correct levels along with balancing the electrolytes to keep you hydrated. Therefore you take half your body weight lb in ounces of water a day. If your 100lb then you would have 50 ounces of water! You then take REAL salt and I highly recommend the best which is Himalayan Salt and you take 1/4 tsp (1250mg) for every litre of water you drink. I strongly suggest you research Dr. Fereydoon Batmanghelidj of whom I learn't this information from.
The Kidneys information from Barefoot is an obvious help as with any clean organ but the facts are without proper drinking of water as the body requires and cleansing foods you will never get the blood pressure to as it should be. If you do find something that gets it down so much without what I've told you above then your in trouble because your most likely artificially lowering your Histamine levels which it is this that regulates the water in the body. The more water the less Histamine and the less water the more histamine. If you use a histamine lowering product you are likely to create serious disease later on. The histamine levels are a water regulator like I said, their actually there to prevent serious damage as a body counter measure. Eventually if prolonged Subclinical dehydration carrys on disease will arise anyhow but to artifically lower histamine whilst still having low water intake is DANGEROUS! You won't hear this information much because one not many realise this and two most are out to make money of Histamine lowering drugs and alternative methods.
Hope you heed the advice!