01 – Definition

What hyperbaric oxygen therapy actually is.

Hyperbaric Oxygen Therapy (HBOT) is the medical practice of breathing oxygen at pressures above sea level, inside a sealed chamber. At normal atmospheric pressure, hemoglobin in red blood cells carries almost all the oxygen in the body and plasma carries very little. Under pressure, oxygen dissolves directly into plasma, cerebrospinal fluid, and tissue fluid — raising tissue oxygen ten to fifteen times baseline.

Every documented effect of HBOT — from wound healing to stem cell release to telomere lengthening — traces back to that one physical change. It is the pressure combined with the oxygen that does the work. Pressure alone does not. Oxygen alone does not.

The Telo chamber implements the protocol at 1.5 ATA (equivalent to roughly 17 feet underwater), with 93% oxygen delivered through a mask rather than filling the chamber itself. This is the mask-delivery configuration used in soft-shell hyperbaric units. It keeps the chamber atmosphere at normal air composition, which is how electronics can operate inside without the fire precautions required by a pure-oxygen atmosphere.

1.5 ATA
Chamber pressure
93% O₂
Via mask delivery
60–90 min
Session length
Henry's Law

What pressure actually does to arterial oxygen.

966
mmHg
Arterial pO₂
9.7×
Dissolved plasma O₂ vs room-air baseline
99%
Hemoglobin saturation — already maxed
Tissue Arterial vessel Tissue

Hemoglobin is already 98% saturated at sea level. Pressure cannot add more oxygen there. What pressure can do is push oxygen directly into plasma, cerebrospinal fluid, and interstitial tissue. At 1.5 ATA with the 93% mask, plasma oxygen runs roughly 10× room-air baseline. That is the mechanism every downstream effect in the next section is built on.

02 – Observed outcomes

What the research shows HBOT does.

The effects below have been measured in peer-reviewed human studies. They are outcomes — what is observed — not yet mechanisms. Each is paired with the sample size and the published source.

Regeneration
Circulating CD34+ stem cells rise roughly eight-fold after a single 2-hour hyperbaric session.Measured in healthy adults. The largest non-pharmacological stem cell mobilization documented to date.
Thom SR et al., 2006Am J Physiol Heart Circ Physiol · n=26 · DOI ↗
+38%Telomeres
60 HBOT sessions lengthened leukocyte telomeres by 20–38% and cleared 10–37% of senescent cells in healthy aging adults.Five days a week for twelve weeks. The first human intervention to move two primary aging biomarkers in one protocol.
Hadanny A et al., 2020Aging · Tel Aviv University · n=35 · Full text ↗
1–5yrBrain recovery
Measurable cognitive and neurological gains in patients 1–5 years post-TBI or stroke, after injury had been considered stable.Randomized controlled crossover design. SPECT imaging showed perfusion changes in previously dormant brain regions.
Boussi-Gross R et al., 2013PLoS ONE · n=56 · Full text ↗
−AβAmyloid
Reduced amyloid-β plaque burden and improved cerebral blood flow in aging patients with memory decline.Mixed cohort of animal model and elderly human patients. Findings suggest HBOT addresses Alzheimer's pathology upstream rather than downstream of plaque accumulation.
Shapira R et al., 2021Aging · Tel Aviv University · Full text ↗
FMChronic pain
40 HBOT sessions significantly reduced fibromyalgia symptom severity; SPECT imaging showed normalized brain activity in pain-processing regions.Treatment-resistant patients, 64% were able to reduce or discontinue medication at study end.
Efrati S et al., 2015PLoS ONE · n=60 · Full text ↗
13FDA indications
Standard-of-care medical treatment for thirteen conditions including carbon monoxide poisoning, decompression sickness, diabetic wounds, radiation injury, and crush injury.Recognized by the Undersea and Hyperbaric Medical Society since 1985. These are clinical indications, not longevity claims.
UHMS / FDAClinical standard · Indications list ↗
On protocols. The studies above span clinical and longevity use cases across the hyperbaric range, with pressures set by indication. The underlying mechanism in every case is the same: elevated arterial oxygen driven by pressure and pure-oxygen delivery. Telo is designed for 1.5 ATA daily home use — the highest pressure a soft-shell home chamber can maintain safely and sustainably.
03 – Mechanism

How this happens at the cellular level.

The outcomes above are driven by three mechanisms that repeat across the hyperbaric literature. All three are downstream of the same cause — elevated plasma oxygen under pressure — and they reinforce each other.

01 – Regeneration

Stem cells released from bone marrow.

Elevated tissue oxygen triggers the release of CD34+ hematopoietic stem and progenitor cells from bone marrow into circulation, where they travel to areas of injury or oxidative stress. Thom's 2006 paper measured an eight-fold rise after a single session. This is the proposed driver of the regeneration and wound-healing effects documented across the hyperbaric literature.

02 – Cellular age

Telomere lengthening and senescence clearing.

Telomeres are the protective caps at the end of chromosomes. They shorten with each cell division, and once they are too short the cell either stops dividing or becomes senescent. In Hadanny's 2020 protocol, 60 HBOT sessions produced 20–38% telomere lengthening in immune cells alongside a 10–37% drop in senescent cell counts — the first human intervention to move both biomarkers in the same study.

03 – Energy

Mitochondrial biogenesis.

Mitochondria produce cellular energy. Sustained exposure to elevated oxygen combined with intermittent pressure stimulates mitochondrial biogenesis — the cell builds new mitochondria and improves the efficiency of existing ones. This is the same adaptive pathway triggered by endurance exercise, arrived at through a different stimulus.

04 – Evidence · 1985 → 2024

Three decades of peer-reviewed research.

HBOT has an unusually long paper trail for a therapy still considered novel in longevity circles. FDA-approved for specific indications since 1985, it has been investigated at academic medical centers in the United States and Israel for regeneration, neurological recovery, cognitive decline, and chronic pain. Every study below links to the published source.

1985FDA approval
Hyperbaric oxygen therapy formally approved.

The UHMS and FDA begin recognizing HBOT as standard care for thirteen indications — carbon monoxide poisoning, decompression sickness, diabetic wounds, radiation injury, and more. HBOT enters mainstream medicine.

UHMS / FDAClinical standard of care
View FDA-approved indications
2006Regeneration
The stem cell paper that changed the conversation.

Thom et al. at the University of Pennsylvania measured an 8-fold increase in circulating CD34+ stem cells after a single HBOT session in healthy adults. Opened the door to HBOT as a longevity intervention, not just a wound-healing tool.

Thom SR et al.Am J Physiol Heart Circ Physioln=26
Read the study
2013Brain repair
Cognitive recovery years after TBI and stroke.

Two Tel Aviv University RCTs (Efrati & Boussi-Gross) showed measurable cognitive and neurological gains in patients one to five years past their injury. Demolished the "recovery window" assumption.

Boussi-Gross R et al.PLoS ONEn=56
Read the study
2015Chronic pain
Fibromyalgia symptom reduction via oxygen.

60 women with treatment-resistant fibromyalgia underwent 40 HBOT sessions. Pain scores dropped significantly; SPECT imaging showed normalized brain activity. Many were able to discontinue medication.

Efrati S et al.PLoS ONEn=60
Read the study
2020Aging reversal
The landmark telomere study.

Hadanny et al. showed 60 HBOT sessions produced 20–38% telomere lengthening and a 10–37% reduction in senescent cells in healthy aging adults. The first human intervention to reverse two primary aging biomarkers simultaneously — the paper the longevity field pointed at all year.

Hadanny A et al.Aging · Tel Aviv Universityn=35
Read the study
2021Alzheimer's
Reducing amyloid burden in aging brains.

Shapira et al. demonstrated HBOT reduces amyloid-β plaques, improves cerebral blood flow, and produces measurable cognitive gains in aging patients with memory decline. Addresses Alzheimer's pathology upstream.

Shapira R et al.Aging · Tel AvivHuman + animal cohort
Read the study
2024And ongoing
Dozens of RCTs in progress worldwide.

Current trials investigate HBOT in long COVID, depression, post-surgical recovery, and healthy aging. The protocol is no longer a debate — the open question is how far it generalizes.

Multiple centersClinicalTrials.gov · active recruitment
Browse active HBOT trials
A note on protocols. The studies above span clinical and longevity work, with pressures set by the condition being treated. Telo is designed for 1.5 ATA daily home use, a pressure chosen to balance physiological effect with sustainability and safety outside a medical setting. Acute clinical conditions are typically run at higher pressures under supervision.
05 – Pressure & trade-offs

The 1.5 ATA decision, and what it trades off.

Pressure is the lever that makes hyperbaric work, and different pressures are suited to different use cases. The Telo chamber operates at 1.5 ATA because that level is where three constraints intersect: it produces the documented physiological effects, it remains comfortable enough for daily use, and it can be safely maintained in a soft-shell unit at home without medical supervision. Here is the trade-off behind each of those constraints.

01 / COMFORT

Ear and sinus equalization.

At 1.5 ATA, ear and sinus pressure differentials are mild and most people equalize during the initial pressurization without discomfort. Above this level, equalization becomes harder and clinical protocols are typically run under supervision. 1.5 ATA is the ceiling for routine unsupervised home use.

02 / FLEXIBILITY

Built for the 40 to 60 session protocol.

Every documented longevity outcome comes from repeated use. Forty to sixty sessions of 60 to 90 minutes, five days a week, across two or three months. That cadence is where the effect lives. A home chamber at 1.5 ATA is the format that actually makes it realistic. The session happens whenever fits your day, and inside the chamber you can nap, read, work, or take a call.

03 / EFFICACY

Physiological effect per session.

At 1.5 ATA with 93% oxygen through the mask, arterial oxygen partial pressure rises roughly 4–5x baseline. This is enough to drive the cellular mechanisms documented in Section 03. For chronic, repeated use the dose-response curve flattens above this range, which is why longevity-oriented protocols tend to cluster here rather than at clinical peaks.

Pressure spectrum

Where 1.5 ATA sits on the clinical-to-home continuum.

Click any point to explore
1.0 ATA Sea level
1.3 ATA Entry home
1.5 ATA Telo
2.4 ATA Hospital
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1.5 ATA / Telo

Equivalent to roughly 17 feet underwater. At this pressure paired with 93% oxygen via mask, arterial oxygen partial pressure rises about 4–5x baseline — enough to drive the cellular mechanisms documented in Section 03. It is the ceiling pressure that a soft-shell chamber can safely maintain for daily unsupervised use, and the level where the dose-response curve for chronic protocols begins to plateau.

Daily home protocol
06 – Limits & contraindications

What HBOT doesn't do, and who it isn't for.

The longevity space tends to overstate what hyperbaric oxygen can deliver and understate its boundaries. This section is the part of the page that sells least. It exists so a reader can decide for themselves whether the protocol fits the problem they're trying to solve.

Medical contraindications

People who should not use HBOT without medical clearance.

HBOT is not safe for everyone. Documented contraindications include:

  • Untreated pneumothorax (collapsed lung). The single absolute contraindication.
  • Active chemotherapy with certain agents (bleomycin, cisplatin, doxorubicin). Oxygen interaction with these drugs can be dangerous.
  • Uncontrolled seizure disorders, severe COPD with CO₂ retention, or recent ear/sinus surgery.
  • Upper respiratory infection or congested sinuses at the time of a session — pressurization can cause ear or sinus barotrauma.

Anyone with a chronic condition should clear HBOT use with their physician before starting a home protocol.

Who this is not for

Cases where HBOT is likely not worth the investment.

  • Anyone who cannot equalize ear pressure reliably. If airline flights or scuba cause persistent ear pain, a daily hyperbaric protocol will not work.
  • People seeking immediate effect. Single-session benefits are subtle; the documented outcomes come from sustained cadence over weeks.
  • Anyone unable to commit to the protocol. Running two sessions a week does not replicate the effect sizes in the longevity literature. Consistency is the active ingredient.

If you've read this far and the protocol makes sense for what you're trying to do, the Telo Protocol chamber is a 1.5 ATA implementation built for daily home use.

Back to the Telo Protocol chamber →