In chemistry, pH is a numeric scale used to specify the acidity or basicity of an aqueous solution.
[https://en.wikipedia.org/wiki/PH from Wikipedia]

pH is a numeric value from 0 to 14 and beyond.  7 is neutral. \\ 

0 > 7 > 14

acid > neutral > base (alkaline)

{| class=wikitable
! style=text-align:left;| pH Value
! style=text-align:left;| Compartment
|-
|0
|hydrochloric acid
|-
|2.5 - 4.0
|Safe Kombucha
|-
|5.5
|human skin
|-
|6.0
|urine
|-
|7.0
|pure water
|-
|7.34 - 7.45
|blood
|-
|7.5 - 8.4
|sea water
|-
|14
|sodium hydroxide
|}

acid-base homeostasis \\ 
acid-alkaline balance \\ 

==Alkaline Diet==

The claims are:

  *  excessive acidity in the body causes disease
  *  eating certain foods can re-balance the ph in the body

The counter-claims:

  *  No diet can affect the pH of any bodily system except the urine.

==notes==
acid: vinegar, kombucha,

alkaline: oil, baking soda

The burning of a food leaves an ash.  It is this ash that remains in the body to make it acid or alkaline.

Citrus fruits are acidic, but burning them produces an alkaline ash.  Therefore, counter-intuitively, eating a citrus fruit increases alkalinity.

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