Kitchen table

The same nine studies, told across the kitchen table

Same nine studies as the rest of the site. Short bits. Take them one at a time.

What it is

Breathing pure oxygen, under pressure

Hyperbaric oxygen therapy — HBOT — means breathing pure oxygen inside a pressurised chamber. The pressure pushes a lot more oxygen into your blood than normal breathing can, and that oxygen reaches parts of the body the blood can't fully supply on its own.

It's real, established medicine. Hospitals already use it as standard treatment for carbon-monoxide poisoning, the bends (a diving injury), radiation damage, and wounds that won't heal. Since 2013 it's also an approved treatment for blocked arteries.

The studies here look at something newer: using HBOT to help the brain — after head injury, concussion, PTSD, stroke, and memory problems.

What the oxygen does inside the brain

It switches on the body's repair systems

HBOT isn't just "a bit more air." Pushing oxygen up and letting it come back down acts like a signal that turns on the body's own repair kit. It does five things.

Brings swelling down

And it does it without starving the tissue. High oxygen makes the blood vessels tighten a little, which lowers the pressure inside the skull — while the tissue still gets fed.

Restarts the cells' engines

The tiny energy factories inside cells start working again, and cells that were about to die are pushed to survive instead.

Grows new blood vessels

So oxygen keeps arriving even after you leave the chamber.

Grows new brain wiring

New connections — which is exactly what you need to get a lost ability back.

Calms the damage

It lowers the inflammation and chemical stress that keep hurting the brain after the first injury.

The important part

It works on the damage itself — no matter what caused it.

What actually happened to patients

Here's the part hardly anyone knows

These treatments helped old injuries. Not fresh ones. People whose brains were hurt one, two, even five years earlier — and they still got better. So "it's too late, nothing can be done now" is not what the research shows.

56
people
2013

Hurt 1–5 years earlier

After HBOT their memory and thinking improved, and so did their quality of life. Brain scans lit up to prove it wasn't in their heads. Nothing changed during the waiting period — only the oxygen made the difference. (Boussi-Gross)

63
people
2020

Under full FDA approval

After 40 sessions: real gains in memory, thinking, sleep, depression, anxiety and PTSD — and it held up months later. (Harch)

strictest
2025

The strictest kind of study

Nobody — not even the doctors — knew who got real oxygen and who got a fake session. The real-oxygen group clearly improved more. (Weaver)

250
pooled
2025

All the studies added together

Big improvements in memory and attention, plus thinking, focus and movement. (Shahid)

154
people
2018

The biggest group

Tested with real equipment instead of just questionnaires — they improved too. (Hadanny)

30
veterans
2017

Brain injury and PTSD

Their brain scans went back toward normal in three out of four damaged areas — and fewer of them wanted to die. (Harch)

The bottom line

Every study points the same way

HBOT works on the injury — a hurt, swollen, oxygen-short brain — whatever caused it.

It is already standard hospital medicine for related injuries.

It's been proven in proper controlled trials, in the strictest blind trial, in a big pooled analysis, and on brain scans — not just opinions.

And it helped brains that had been hurt for years. The door doesn't slam shut.

Fair notes. The studies aren't huge, and doctors haven't yet agreed on the exact dose — how much pressure, how many sessions. Researchers say bigger trials are still needed. That's normal for a treatment spreading into new uses. It's not the same as saying it doesn't work.
So when someone calls it "experimental" or "too late," the studies in this file say otherwise.