Experts believe that dehydration is a leading cause of Jet Lag, and it is universally agreed that dehydration worsens all symptoms of Jet Lag. When you’re in a dry environment (airplane cabins, desert areas, heated homes & buildings, mountains and high elevation etc.) you lose a lot of moisture every time you exhale. The resulting moisture loss from your body can cause diminished blood flow to muscles, reduced kidney function, and fatigue. In addition, low humidity causes dry nasal passages which are more susceptible to viruses and infection. Dry air will also aggravate allergies, asthma & COPD by drying the delicate membranes of the nose and respiratory tract. Not to mention that it’s just plain uncomfortable to have a dry nose and throat.
You can, and you should! But have you noticed that your nose still gets dry when you’re in an airplane or the desert, even if you drink a lot of water? That’s because your nose gets the moisture to humidify inspired air from some very complex sources… Meaning, it’s a long haul from that glass of water and a lot of that fluid is going to be diverted along the way to sweat, saliva, digestion etc. The key is to avoid the moisture loss in the first place!
The average outdoor humidity in the US is around 66%, though depending on the region, altitude and time of year it’s often much lower. A heated/air conditioned building falls around 25 – 30%, and a commercial aircraft drops all the way to 15%. To put this in perspective, the average humidity of the Sahara desert is 25%…10% MORE than on an airplane! No wonder we ‘lag’ when we land.