Short History of the Water Pipe (AKA The Bong)
Water pipes have been used for centuries by different people throughout the world. Prior to recent discoveries, it was thought that the first water pipes where introduced into the Ming Dynasty in the 16th century. These where transported to China from the Silk Road from Persia and other empires. They where used by commoners, but royalty employed the use of bongs as well, including the imperial mistress, Empress Cixi, as a preferred method for tobacco ingestion. She was buried with at least 3 of her prized pieces, some of which can now be seen on display in the Palace Museum in Beijing.
More recently though, it has been discovered that the use of water pipes dates back before the Common Era. During an excavation of a power line in Russia in 2013, gold water pipes where discovered in tribal remains (Scynthians) which date back to around 400 BCE (approximately 2400 years ago). These pipes where made of pure gold... and you thought you had a baller collection of glass.
Why they are Better for Your Lungs
When you use a water pipe, you are utilizing a physics phenomenon known as active osmosis. This is a method transporting molecules across a permeable membrane (in the smoking world these are known as percolators, but water also acts as a permeable membrane). Active diffusion is simply using some kind of energy (active) to transport molecules (water and smoke with its constituents) across a membrane. The energy we use to achieve this is air pressure, which is created when you pull on a water pipe. The water creates a gradient which is utilized to filter the smoke across a membrane. This membrane filters out some of the elements of smoke which are harmful to your lungs. Interestingly, this can also alter the makeup of the smoke you inhale (fortunately, it appears to always alter it in a positive way).
Now that we have the physics sorted out, let's delve into why it's better. As we all know, water as well as percolators serve to filter smoke. This has been studied by various groups and some interesting results where derived. Just keep in mind, all smoke is harmful to some degree.
First of which is the interesting affect on our physiology's ability to fight bacteria. MAPS discovered that when tobacco smokers lungs where exposed to unfiltered smoke, their lungs (specifically the macrophages therein, which consume foreign invaders tagged by our immune system) actually had a diminished ability to combat bacteria also inhaled during smoking. On the contrary, filtered smoke lessened this effect and our cells had an easier time. Even more amazing, there is scientific evidence that tobacco smokers that utilized a water pipe have a lower incidence of carinoma (cancer in our body's lining) in comparison to cigarettes, cigars, and regular pipes. Puff on that knowledge. There are many adaptations which glass blowers utilize to make smoking from them a smoother experience, as well. These include ice pinches, multiple chambers, and or variations in design (such as recyclers). If you want to eliminate virtually any stress or potential damage on your lungs, consider a vaporizer.