What is the longest anyone has survived without oxygen?

October 1, 2025 •

5 min read

In June 2025, Croatian freediver Vitomir Maričić set a Guinness World Record by holding his breath for 29 minutes and 3 seconds, yet the longest anyone has survived without oxygen often involves different circumstances, such as accidents and medical interventions. While average human survival without air is a mere few minutes, extreme physiological feats and specific environmental conditions can dramatically alter the timeline.

Quick Summary

The longest survival without oxygen varies significantly between voluntary, highly-trained breath-holds and involuntary, medically-influenced cases. Factors like pre-breathing pure oxygen, body temperature, and accidental immersion explain why some individuals survive far beyond the normal human limit of a few minutes, though with high risk of brain damage.

Key Points

Oxygen-Assisted Record: The longest voluntary breath-hold is 29 minutes and 3 seconds, achieved by freediver Vitomir Maričić using pure oxygen pre-breathing in June 2025.
Unaided Breath-Hold Record: Without pre-breathing oxygen, the longest breath-hold is 11 minutes and 35 seconds, set by Branko Petrović.
Average Human Limit: The average person can only survive 3 to 5 minutes without oxygen before irreversible brain damage occurs, though this can vary.
Hypothermia's Role: Extreme cold, such as icy water, can significantly extend survival time by slowing the body's metabolism, as seen in some drowning cases.
Commercial Diver Case: Chris Lemons survived 38-40 minutes without oxygen at depth in a famous survival case, largely due to training and his body's dive reflex.
Brain Damage Risk: Beyond 10-15 minutes of anoxia, severe and permanent brain damage is virtually certain without significant medical intervention.

The Body's Critical Need for Oxygen

The human body is a highly efficient machine, but it requires a constant supply of oxygen to function. The brain, in particular, is an energy-intensive organ that consumes about 20% of the body's total oxygen intake. When the oxygen supply is cut off, a cascade of physiological failures begins. Without oxygen, cellular respiration—the process that produces the body's primary energy currency, adenosine triphosphate (ATP)—ceases. This rapid energy depletion is why the average human can only survive a matter of minutes without air before experiencing irreversible brain damage or death. However, the recorded instances of prolonged survival, often under highly specific and extreme conditions, reveal the extraordinary adaptability and resilience of the human body.

World Records: The Apex of Voluntary Breath-Holding

When considering voluntary breath-holding, a distinction must be made between 'unaided' and 'oxygen-assisted' attempts. These are performed by highly-trained freedivers who push the boundaries of human physiology under controlled conditions.

Oxygen-Assisted Record: The current Guinness World Record for the longest voluntary breath-hold is 29 minutes and 3 seconds, set in June 2025 by Croatian freediver Vitomir Maričić. Before the attempt, Maričić used a technique called 'denitrogenation,' breathing pure oxygen for several minutes to supercharge his blood and tissue with oxygen. This drastically extended his survival time far beyond what would be naturally possible.
Unaided Record: The longest unaided static apnea record is 11 minutes and 35 seconds, set by Serbian Branko Petrović in 2014. This record is achieved without the aid of pre-breathing pure oxygen, relying solely on the diver's natural lung capacity and physiological control.

The Science Behind Extreme Breath-Holding

Freedivers undergo years of intense physical and mental training to achieve these astonishing times. Their preparation and abilities involve several key factors:

Increased Lung Capacity: Training helps freedivers increase their total lung volume and efficiency in oxygen absorption.
Diving Reflex: When submerged in water, the body triggers a mammalian diving reflex, which conserves oxygen by slowing the heart rate, constricting blood vessels in the extremities, and redirecting oxygenated blood to the vital organs.
CO2 Tolerance: The urge to breathe is triggered by a buildup of carbon dioxide, not a lack of oxygen. Freedivers train to tolerate much higher CO2 levels, allowing them to suppress the urge to breathe for longer periods.
Mental Control: Remaining calm and avoiding panic is crucial, as anxiety accelerates oxygen consumption. Mental discipline allows them to push past the body's natural alarms.

Medical Cases and Environmental Factors

Outside of controlled record attempts, remarkable survival stories reveal how specific environmental and medical factors can alter the outcome of severe oxygen deprivation.

The Hypothermia Effect

Cold water is perhaps the most significant environmental factor. Hypothermia, a state of low body temperature, dramatically slows down the body's metabolism and its demand for oxygen. This can buy precious time for survival, especially in children, whose bodies are more responsive to this effect. Medics have a saying for cold water drowning cases: "You're not dead until you're warm and dead". A case from 1986 involved a 2-year-old child who survived approximately 66 minutes of submersion in icy water in Norway. The child was revived with a good neurological outcome, thanks to the protective effects of hypothermia.

Remarkable Survival in Extreme Conditions

One extraordinary case is that of commercial diver Chris Lemons, who survived 38-40 minutes without an umbilical oxygen supply while trapped on the North Sea seabed in 2012. His crew's rescue efforts and his survival against all odds became the subject of the documentary Last Breath. While Lemons had access to a small, six-minute emergency air tank, the prolonged period was attributed to his body's natural physiological adaptations under pressure, his deep-sea diving training, and a measure of sheer luck. He ultimately suffered no lasting ill effects, a testament to the unpredictable nature of extreme survival.

Oxygen Deprivation and the Brain

Understanding the timeline for brain damage during oxygen deprivation (anoxia) is critical for emergency medicine. A breakdown of the typical timeline for an average person at a normal body temperature is as follows:

0-30 seconds: Loss of consciousness may occur as the brain's oxygen stores are depleted.
1 minute: Brain cells begin to die.
3 minutes: Neurons suffer more extensive damage, and lasting brain injury becomes possible.
5 minutes: The risk of severe, long-term brain damage increases significantly.
10 minutes: Most brain activity stops, making severe brain damage highly likely.
15 minutes+: Survival is nearly impossible, even with medical intervention.

This narrow window of survivability without damage highlights the difference between an untrained individual and a trained freediver or a person in hypothermic conditions. For example, therapeutic hypothermia is used in newborns with birth-related oxygen deprivation to slow metabolic activity and reduce the risk of permanent brain injury.

Comparison of Survival Factors


Factor	Voluntary Breath-Hold (Freediver)	Involuntary Deprivation (Accident)
Preparation	Years of physical and mental training; optional oxygen pre-breathing.	None. Unforeseen circumstances.
Conditions	Controlled environment (pool or open water); deliberate mental state.	Uncontrolled (e.g., drowning, strangulation, high altitude); panic and stress are common.
Body State	Calm, low metabolic rate, activated diving reflex.	High metabolic rate due to panic, struggling; less efficient oxygen use.
Environmental Impact	Minimal effect, or leveraging the dive reflex in water.	Extreme environmental factors, especially cold temperatures, can significantly alter survival time.
Brain Damage Risk	Extremely high risk if pushed too far, even with training.	High risk after a few minutes; risk can be mitigated by hypothermia.
Survival Outcome	Record is the goal; neurological recovery is paramount.	Survival is the goal; neurological recovery is less certain and can be impacted by duration.

Conclusion

The question of what is the longest anyone has survived without oxygen has no single, simple answer. The duration of survival depends on a complex interplay of factors, including training, environment, and medical intervention. While the average person faces irreversible brain damage in just a few minutes, highly specialized freedivers can hold their breath for a quarter of an hour or more, especially with oxygen pre-breathing. In cases of accidental oxygen deprivation, environmental conditions like cold water can dramatically extend the timeline, sometimes allowing for miraculous, though risky, recoveries. These extraordinary examples highlight the intricate physiological mechanisms of the human body and remind us of both its fragility and its remarkable capacity for resilience under extreme stress.

For more information on the effects of oxygen deprivation on the brain and therapeutic interventions, you can visit the Headway website.

Frequently Asked Questions

The world record for the longest voluntary breath-hold without any pre-breathing of pure oxygen is 11 minutes and 35 seconds, achieved by Serbian freediver Branko Petrović in 2014.

The average person can typically last only 3 to 5 minutes without oxygen before experiencing irreversible brain damage. Survival for longer than 10-15 minutes is rare without external factors or intervention.

The freediver, Vitomir Maričić, achieved this record by pre-breathing pure oxygen for 10 minutes beforehand, a technique called denitrogenation. This flooded his system with a much higher concentration of oxygen than normal air, allowing for an extended breath-hold.

Yes. Hypothermia, or a lower body temperature, can dramatically slow the body's metabolism and oxygen consumption. There have been documented cases, particularly involving children, who have survived surprisingly long periods of cold water submersion with a positive outcome, a medical phenomenon referred to as 'not dead until warm and dead'.

Without oxygen, brain cells begin to die almost immediately due to a lack of energy production. As time progresses, damage becomes more widespread, leading to loss of consciousness, coma, and potentially permanent brain damage or death within minutes.

Hypoxia refers to a partial lack of oxygen supply to tissues, while anoxia is a complete absence of oxygen. Both can cause brain injury, but the effects of anoxia are more immediate and severe.

Therapeutic hypothermia is a medical treatment that involves carefully cooling a patient's body to slow down metabolic activity. This reduces the brain's need for oxygen and can help minimize permanent brain damage after an oxygen-depriving event, particularly in newborns.