The question of whether drinking nitrogen is harmful depends entirely on the state of the nitrogen being consumed. Nitrogen is a colorless, odorless gas that makes up approximately 78% of the air we breathe. It exists in consumer products in two forms: as a harmless, dissolved gas in beverages or as a cryogenic liquid that is profoundly dangerous if ingested. The danger lies not in the element itself, but in its temperature and the extreme volume change it undergoes when transitioning from a liquid to a gas.
Nitrogen Gas Dissolved in Consumer Beverages
Nitrogen gas is widely used in the beverage industry to enhance product quality and texture. When dissolved into liquids, such as in “nitro” coffee or certain beers, the nitrogen remains in a gaseous state, simply suspended within the drink. Nitrogen is an inert gas, meaning it is chemically non-reactive and non-toxic, making this application inherently safe for consumption.
The gas is poorly soluble in water and blood, which is why it creates a dense, fine-bubble structure that gives beverages a characteristic velvety mouthfeel. Unlike carbon dioxide, which creates large, sharp bubbles and carbonic acid that causes an acidic bite, nitrogen bubbles are small, giving the drink a smooth, creamy texture. The small amount of dissolved nitrogen is easily expelled from the body through normal respiration, similar to the carbon dioxide in carbonated sodas.
Defining Liquid Nitrogen and Its Properties
The hazardous form of nitrogen is Liquid Nitrogen, commonly referred to as LN2. This is nitrogen in a cryogenic state, meaning it has been cooled to an extremely low temperature of approximately -196°C (-320°F). At this temperature, the gas condenses into a clear, colorless liquid that is used commercially for flash-freezing and creating dramatic vapor effects in novelty foods and drinks.
The primary danger of LN2 stems from its massive volume expansion upon warming. When one volume of liquid nitrogen converts back into gas at room temperature, it expands to approximately 694 times its original volume. This enormous expansion ratio generates immense pressure if the gas is confined. This phase change is instantaneous when the liquid contacts anything warmer than its boiling point, including human tissue.
Acute Physical Trauma from Ingestion
Ingesting even a small amount of liquid nitrogen can lead to severe injuries due to two combined mechanisms: severe cold and barotrauma. The extreme temperature of LN2 causes instantaneous cryogenic burns (frostbite) to any tissue it contacts, including the mouth, throat, and esophagus. This exposure can lead to tissue necrosis, which is the death of cells.
The more immediate injury is barotrauma, which is damage caused by pressure. Once swallowed, the liquid nitrogen is rapidly heated by the body’s internal temperature, causing it to vaporize almost instantly inside the gastrointestinal tract. This sudden conversion into gas, expanding nearly 700 times its liquid volume, creates an intense internal pressure within the confined space of the stomach.
This rapid pressure buildup can cause the stomach to rupture, a condition known as gastric perforation. The perforation allows the contents of the stomach and the expanding nitrogen gas to leak into the abdominal cavity, leading to a medical emergency that requires immediate surgery, often resulting in the removal of part or all of the stomach.
Respiratory and Pressure Hazards
The secondary risks associated with liquid nitrogen exposure involve the large volume of nitrogen gas produced during vaporization. When LN2 is used in food or spilled in a confined area, the gas it rapidly creates can displace the surrounding air. Nitrogen gas is nontoxic, but it acts as a simple asphyxiant by lowering the concentration of oxygen in the atmosphere below the level required to sustain life.
This oxygen displacement can cause dizziness, vomiting, loss of consciousness, and death, often without any warning because nitrogen is colorless and odorless. Even if perforation does not occur, the rapid expansion of gas within the digestive tract can cause severe internal pressure effects known as barotrauma. This can lead to extreme gastrointestinal swelling and distress, potentially damaging internal structures.