Oxygen bars vs hyperbaric oxygen therapy: what each one actually delivers

Oxygen bars sell a few minutes of scented oxygen, breathed through a thin tube, with promises of more energy, less stress or a clearer head. Because hyperbaric oxygen therapy also involves breathing oxygen, people sometimes assume the two are versions of the same thing. Physically they are very different. This guide explains what an oxygen bar delivers, what the evidence says, the safety points worth knowing, and what hyperbaric oxygen can and cannot claim.

What is an oxygen bar?

At an oxygen bar you breathe oxygen through a plastic tube inserted into your nostrils, called a nasal cannula. A US Food and Drug Administration consumer article describes sessions lasting from a few minutes to about 20 minutes, often with "flavoured" oxygen made by pumping it through a scent on its way to the nose.

Two details matter:

• The pressure is normal. You sit in an ordinary room at ordinary atmospheric pressure.
• The oxygen is diluted. Room air mixes with the oxygen from the tube, and passing it through a scent lowers the concentration further. The FDA article quotes one supplier saying customers get less than 50 percent oxygen. The air around us is about 21 percent oxygen.

Oxygen bars are promoted for reducing stress, increasing energy and alertness, and easing hangovers, headaches and sinus problems. The same article states that there are no long-term, well-controlled scientific studies supporting these claims for oxygen in healthy people. It was written in 2002 about the United States, but the physiology it describes has not changed.

Do oxygen bars actually work?

Start with where the oxygen goes. Oxygen saturation is the proportion of haemoglobin, the oxygen carrier inside red blood cells, that is bound to oxygen. A StatPearls review gives normal peripheral oxygen saturation as 95% to 100% in healthy people at sea level. If your haemoglobin is already close to full, extra oxygen at normal pressure has very little room to add more.

The oxygen dissolved directly in plasma is small too. A StatPearls review of hyperbaric physics puts it at about 3 mL per litre at normal pressure, while resting tissue needs roughly 60 mL per litre.

Oxygen bars have also been tested directly. In a 2011 randomised study, 30 healthy adults were split into two groups of 15. Each person spent 10 minutes receiving oxygen through a nasal cannula and 10 minutes with the oxygen bar running but no oxygen delivered, in opposite orders. There were no significant differences in energy, relaxation or stress levels. The study was small, short and based on questionnaires, but it is a direct test of the main claims.

Medical guidance points the same way. The British Thoracic Society guideline states that oxygen is a treatment for hypoxaemia, meaning low blood oxygen, not for breathlessness, and that it has not been shown to have any consistent effect on breathlessness in people whose oxygen levels are normal. For people with COPD who have mild or no low oxygen at rest, NICE advises against offering ambulatory or short-burst oxygen to manage breathlessness.

If you enjoy the scent or the break, that is a personal choice. Expecting a health benefit is not supported by the evidence.

Is an oxygen bar safe?

For a healthy person, the FDA article says breathing these low levels of oxygen may not hurt, while quoting an FDA lung specialist who said people have nothing to gain and take on unnecessary risk. The American Lung Association, quoted in the same article, said there was no evidence that oxygen at the low flow levels used in bars is dangerous to a normal person's health. The cautions are specific:

• Scented oils. Some bars create aromas with oils. Inhaling oily substances can cause a serious lung inflammation called lipoid pneumonia. Even oil-free scents can carry allergens or irritants that may make susceptible people wheeze.
• Heart and lung conditions. The FDA article says people with some types of heart disease, asthma, congestive heart failure, pulmonary hypertension and COPD, such as emphysema, need their oxygen carefully regulated and should not go to oxygen bars. The BTS guideline warns against excessive oxygen in COPD, because it increases the risk of respiratory acidosis in people with hypercapnic respiratory failure, where carbon dioxide builds up in the blood.
• Previous chemotherapy. The FDA article adds that people who have received the chemotherapy drug bleomycin are at risk if exposed to high levels of oxygen for too long.
• Fire. Oxygen feeds combustion. NHS guidance on home oxygen advises no smoking nearby, keeping equipment at least 3 metres from open flames such as gas cookers, at least 1.5 metres from other electrical appliances, and avoiding oil-based emollients such as Vaseline.

The NHS also warns that buying oxygen online and using it without a prescription can be dangerous, and could damage the brain, heart and lungs or even cause death. If you have a heart or lung condition, or have had cancer treatment, ask your GP or specialist before trying an oxygen bar.

How is breathing oxygen under pressure different?

The difference is pressure. Henry's law says the amount of a gas that dissolves in a liquid is directly proportional to the pressure of that gas above it. NHS England describes hyperbaric oxygen therapy (HBOT) as the delivery of oxygen at a pressure greater than normal, so that a higher level of oxygen can be dissolved in the blood plasma.

The StatPearls physics review gives the scale: plasma oxygen rises from about 3 mL per litre at normal pressure to about 60 mL per litre during HBOT at 3 ATA. That extra oxygen travels dissolved in plasma rather than relying on haemoglobin, which is why pressure can do something that breathing more oxygen at normal pressure cannot. An oxygen bar runs at room pressure with a diluted mix, so it cannot produce this effect.

Pressure has effects of its own. Boyle's law means gas spaces shrink as pressure rises, which is why your ears feel full as a chamber pressurises and why people are screened before treatment. Our guide to who HBOT is not suitable for covers those questions. At HBOT Medics, one person at a time breathes concentrated oxygen in a soft-shell chamber at 1.5 ATA, so the dissolved oxygen is lower than in the 3 ATA example, but it is still oxygen under pressure rather than a nasal tube at room pressure. You can read more about what HBOT is.

	Oxygen bar	Hyperbaric oxygen therapy
Pressure	Normal room pressure	Raised pressure inside a sealed chamber
What you breathe	Oxygen through a nasal cannula, diluted by room air and scent	Concentrated oxygen at pressure
Main physical effect	Little change in healthy people already 95 to 100% saturated	More oxygen dissolved in blood plasma
Evidence	No long-term controlled studies supporting health claims in healthy people	Routinely commissioned by NHS England for decompression illness and gas embolism; other uses under research
Main safety points	Scented oils, heart and lung conditions, fire	Ear and sinus pressure, medical screening, oxygen fire safety

What does hyperbaric oxygen evidence show, and what does it not?

More oxygen in plasma is a mechanism, not an outcome. HBOT still has to show in trials that it helps a particular problem.

• Established uses are narrow. NHS England routinely commissions HBOT for decompression illness and gas embolism, and does not routinely commission it for several other uses, including carbon monoxide poisoning and diabetic foot ulcers.
• Advertising claims need trial evidence. The ASA and CAP say they have yet to see convincing evidence that using hyperbaric oxygen chambers as an alternative therapy is effective in treating health conditions, and expect advertisers to hold clinical trial evidence before claiming to treat any condition.
• Research is active and mixed. In a 2025 double-blind trial of 47 adults with persistent symptoms after brain injury, 40 sessions at 1.5 ATA improved symptom scores more than sham, but the trial recruited about a third of its intended sample. An earlier military trial of 72 service members at the same pressure found no benefit over sham. Our head injury page sets out both.

So hyperbaric oxygen is a medical treatment with defined uses, ongoing research and its own screening and risks. An oxygen bar is a recreational experience without good evidence of health benefits. Neither should replace medical care for a health problem.

To see what a session involves from start to finish, read what happens in an HBOT session. If you want to discuss whether hyperbaric oxygen is relevant to you, you can see available times. No referral needed. Medical consultation included.