And seeing as you asked about juice here's my final post/ info:
Juice Components
Flavoring usually about 15%- could be higher or lower depending on the flavor used.
PG enhances flavor, TH/ throat hit and lung hit- water like - many of us believe PG to be a throat irritant.
VG= vapor and can mute flavor- thick
Nicotine- TH, lung hit and our need for nicotine. The MOST important ingredient in regards to TH and lung hit.
Standards in the industry are 80/ 20 or 70/ 30 PG/ VG.
Nicotine levels are 0, 6, 12, 18, 24 and 36 mg. Most new vapers begin at 18 or 24 mg.
Vaping and Dehydration
PG and VG are humectants...
A humectant is a substance used primarily in foods and cosmetic products to help retain moisture. These substances are called hygroscopic, which means that they are able to absorb ambient water. These hygroscopic compounds posses a chemical structure that attracts water from the atmosphere and binds it to various sites along the molecule.
When we inhale PG/ VG it "traps" the moisture in our mouth, throat and nasal area and thus the vapor. The real problem arises when the body is dehydrated and begins "stealing" moisture from other parts of the body to keep key organs hydrated. Add to that more than 3 cups of java or caffeine based soda drinks and severe dehydration can occur.
I had a convert that didn't believe vaping was dehydrating. I showed him his fingernails- there were vertical rails on them. Told him this was a sign of serious dehydration. He began drinking water/ hydrating and within a couple of months his fingernails returned to normal...he's now a believer. Ask any chemist and they will tell you the same. I drink 2+ liters of water per day and no more than 3 cups Java per day.