The Nutrition Diet: Is eating snowballs bad for you?

November 5, 2025 •

3 min read

While catching a few snowflakes on your tongue is often seen as harmless, the question of whether it's okay to make a snack out of them is more complex. Experts warn that is eating snowballs bad for you depends entirely on the snow's source, purity, and the amount consumed, with potential risks far outweighing any perceived benefits.

Quick Summary

This article explores the hidden dangers of consuming snow, detailing how it collects pollutants, bacteria, and chemicals from the air and ground. It clarifies the risks of contamination and explains why eating large quantities can lead to dehydration and hypothermia, offering crucial safety tips for winter recreation.

Key Points

Contaminants are Hidden: Snow is not pure, collecting pollutants like chemicals, dirt, and bacteria as it falls and sits on the ground.
Risk of Illness: Eating contaminated snow can cause gastrointestinal issues, bacterial infections, and other health problems, especially for children and those with weak immune systems.
Dehydration is a Danger: Consuming large quantities of cold snow can dehydrate you by forcing your body to expend more energy to melt it than it gains in water.
Hypothermia Risk: Ingesting large amounts of cold snow can lower your core body temperature, increasing the risk of hypothermia.
Fresh is Best, But Not Guaranteed: Even fresh, white snow isn't necessarily pristine and is safest avoided if possible, particularly in urban or industrial areas.
Avoid Discolored Snow: Never eat snow that is yellow, grey, brown, or any other color, as this is a clear sign of contamination.

Contaminants: More Than Just Water

While snow appears to be nothing more than frozen water, it is far from pure. As snowflakes form and descend through the atmosphere, they act like tiny sponges, absorbing a variety of airborne pollutants and contaminants. This means that the snow you see is also a collection of the impurities in the air around you, and this includes more than just harmless dust.

Where Contamination Comes From

Atmospheric Pollutants: Snow traps a range of substances from the air, including black carbon from wood-burning stoves and vehicle emissions, chemical contaminants, and tiny bits of plastic (microplastics).
Ground-Level Contaminants: Snow that has landed on the ground can collect harmful elements from the surface. This includes dirt, pesticides, and fertilizers. Snow near roads and sidewalks is particularly hazardous due to contact with road salts, antifreeze, oil, and other chemicals from vehicles.
Biological Agents: Snow is not sterile. It can become contaminated with bacteria and animal waste, including E. coli, especially if it sits on the ground for a while or is near areas with animal activity.

Health Risks of Ingesting Contaminated Snow

For most healthy individuals, eating a small, clean-looking amount of snow might not cause serious harm, but the risks increase significantly with larger quantities or compromised snow. The potential health problems can range from mild stomach upset to more severe illnesses.

Potential Side Effects

Eating contaminated snow can lead to various gastrointestinal issues. Case reports have linked ingesting snow from the ground to unusual bacterial infections in children. The specific symptoms depend on the type and concentration of contaminants present, but they can include:

Stomach cramps and pain
Vomiting
Diarrhea
Fever and chills, in cases of more severe infection

The Dehydration and Hypothermia Myth

Counterintuitively, relying on snow for hydration, particularly in a survival situation, can be detrimental. Eating large amounts of very cold snow can actually lead to dehydration and put you at risk of hypothermia.

The Science Behind the Risks

When you ingest cold snow, your body must expend energy to melt it and bring it up to body temperature. This process uses up more energy and fluids than the snow provides, leading to a net loss of hydration over time. For someone already struggling with cold exposure, this can dangerously lower core body temperature, putting them at risk of hypothermia.

Safe Snow vs. Unsafe Snow: A Comparison

To highlight the difference between safe and unsafe consumption practices, here is a comparison chart summarizing the key factors to consider.


Feature	Potentially Safe (in moderation)	Unsafe (Avoid at all costs)
Appearance	Pristine white, fluffy, and clean.	Any discoloration (yellow, brown, grey, black).
Source	Top layer of snow, collected freshly in an undisturbed, rural area.	Snow from the ground, near roads, driveways, or industrial areas.
Contaminants	Minimal atmospheric pollutants, considered safe in small quantities.	High risk of containing road salt, antifreeze, animal waste, and heavy metals.
Health Impact	Unlikely to cause serious issues for healthy people in small amounts.	Possible gastrointestinal upset, infection, or poisoning, especially for vulnerable individuals.

Conclusion: The Verdict on Your Winter Treat

The innocent childhood pastime of eating snow is, unfortunately, not as harmless as it may seem. While a single, tiny, fresh snowflake caught on the tongue is unlikely to be a problem, intentionally eating snow, especially in snowball form, is generally a bad idea. The risks of consuming pollutants, bacteria, and chemicals, along with the physiological strain of dehydration and hypothermia, far outweigh the fun. The safest and healthiest approach is to admire the pristine winter wonderland from a distance and leave the snowballs for building snowmen. For more information on environmental contamination, visit the EPA's website on acid rain, which also affects snow.

Frequently Asked Questions

While a small amount of pristine, fresh snow in a rural area is unlikely to cause serious harm, experts still advise caution. Snow can carry airborne pollutants and is almost never completely pure, so it's safer to avoid it.

Yellow snow is a common and obvious sign of contamination, most famously from urine. It can also get its color from pollen, sand, and other surface pollutants.

Yes, eating large quantities of snow can dehydrate you. Your body expends a significant amount of energy to melt the snow into a usable liquid, a process that can use more fluids than it provides, leading to a net fluid loss.

Dogs face similar risks to humans when eating snow, including ingesting contaminants like road salt, antifreeze, and bacteria. Too much snow can also lead to stomach upset, gastritis, and hypothermia in dogs.

No, the first snowfall is often the dirtiest because it washes the pollutants out of the air as it falls. Later, successive snowfalls tend to be cleaner after the initial 'air-cleaning' effect has occurred.

Ingesting small amounts of snow is unlikely to cause hypothermia. However, eating large quantities, especially in a situation where body temperature is already compromised, can dangerously lower core body temperature.