The moment we turn on the heater in our home is the exact moment the humans in my house (myself included) begin waking up with scratchy throats, chapped lips, increasingly dry skin, middle of the night coughs and so on.
Did you know that most heaters in northern states come with humidifiers? So, what happens is the temperature of air determines how much water vapor the air can hold. As temperature increases, water vapor capacity increases as well. The colder the temperature is, the drier the air must be, because of its reduced moisture capacity. During the winter months the environment of our home changes and our heaters exaggerate the dryness by increasing temperatures but not changing the moisture content. This scientific explanation helped my brain comprehend(or justify) the need for each diffuser in our home. Not only do they allow us to inhale the oil that is essential for our body or mind at any given time, they are also putting water droplets <moisture> back into our home environment. This hydrates our largest organ, skin, and helps with any respiratory/sinus discomfort! So keep your diffusers out and running through winter and remain hydrated and well.