If you are working up a sweat doing winter sports or are outside playing with your children in the freshly fallen snow and all around you there are immense white fields just inviting you to roll up that first snowball, or maybe you are trekking up the mountainside… whatever the case may be, you are thirsty and wondering if eating some snow might help!
Did you know that snow is condensation from water vapor formed at the saturation point in the upper layers of the atmosphere? When it comes into contact with cold air, it crystallizes and forms flakes that not only contain water molecules, but air as well (which is why it is light and fluffy). The water is completely demineralized and very cold (0°C).
That being said, if you eat snow occasionally for fun, it will first cause a slight thermal shock to your teeth, then to your stomach, and can actually decrease your body temperature. Not exactly ideal when you are trying to warm up!
Moreover, there is also the issue of cleanliness. Of course, no one would think to eat dirty snow off the sidewalk or from where animals have done their business, but just because snow is white does not mean that it is necessarily clean. In fact, bacteria and viruses can travel quite easily with the wind and can contaminate powder snow. So you are definitely not eating germ-free snow! That is the reason why mountain climbers always boil snow before they drink it. (Did you know that the higher you climb the faster water boils?)
Furthermore, water from snow is demineralized. This does not have any negative effects if taken in small doses, but if you consume a substantial amount (at least 1 liter per day) over a period of time (several days), it can have harmful effects on the body due to cellular hyperhydration caused by a decrease in osmotic concentration of the blood (headaches being the first symptom) (1).
That is why mountain climbers usually also add a bit of salt, tea or soup to snow water after boiling it and beating it with a whisk to oxygenate it, in order to increase mineralization.
All in all, you can see that snow is not so easy to treat and requires a certain amount of precautions.
The easiest thing would be to just keep a small bottle of mineral or spring water with you. At least it is naturally almost germ-free and is somewhat mineralized from the rocks it has travelled through while flowing underground.
After all, water from the depths of the earth is healthier for you than water from the sky!