Study 01 Stress

Calmer than
sleeping.

By one stress measure, humming scored below sleep.

Lowest
stress index of every state measured

What they found

Using continuous Holter heart monitoring, this pilot study tracked the same 23 people across four states: humming, physical activity, emotional stress, and sleep. Humming produced the lowest stress index of all four, with other heart-rate-variability changes consistent with reduced stress.

Why it matters

It puts a number on something humming practitioners describe by feel. By this stress measure, the humming state scored lower than the sleeping state in the same people.

23 adults
Participants
Pilot study
Design
Holter monitoring
Duration
The bottom line
Lower stress than physical activity, emotion, or sleep.
The source
Trivedi et al., 2023
PubMed
Study 02 Nervous system

Retunes the
nervous system.

The largest trial to date, and it moved the needle.

520
people in a randomized controlled trial

What they found

Over six months, 520 students were randomly assigned to humming five days a week or to a control group. The humming group's short-term heart-rate-variability shifted significantly toward parasympathetic, "rest and digest" dominance.

Why it matters

Higher vagal tone is one of the most reliable physiological signatures of resilience: steadier heart rate, better stress recovery, stronger emotional regulation. This is that shift, at scale, in a gold-standard design.

520 students
Participants
Randomized trial
Design
6 months
Duration
The bottom line
Daily humming trained a measurably calmer baseline.
The source
Kuppusamy et al., 2020
PubMed
Study 03 Calm response

A shift in
five minutes.

One short session nudged the nervous system toward calm.

5 min
to a measurable parasympathetic shift

What they found

In 70 patients with high blood pressure, a single five-minute hum significantly raised high-frequency (calming) heart-rate-variability power and lowered low-frequency (stress) power, versus a comparison breathing exercise. Blood pressure itself did not drop after one session, but the autonomic shift was clear.

Why it matters

The shift showed up immediately, in people with diagnosed hypertension, after one short session, with no weeks of practice required. It points to the nervous-system effect, not a blood-pressure cure.

70 patients
Participants
Randomized trial
Design
Single session
Duration
The bottom line
A clear parasympathetic shift, captured on the monitor.
The source
Ghati et al., 2021
PubMed
Study 04 Stress hormone

Faster cortisol
recovery.

The body cleared the stress hormone quicker under pressure.

Cortisol
regulated better after a lab stressor

What they found

In a six-month randomized trial, adolescents faced a standardized stress test while researchers tracked salivary cortisol. The humming group showed a sharper early response and significantly lower cortisol an hour later, the profile of a system that recovers faster.

Why it matters

Cortisol is the body's main stress hormone. Clearing it efficiently after a stressor, rather than staying flooded, is what healthy stress recovery actually looks like biologically.

26 adolescents
Participants
Randomized trial
Design
6 months
Duration
The bottom line
A trained, faster comedown from stress.
The source
Maheshkumar et al., 2021
PubMed
Study 05 Tinnitus

Quieter ringing
in the ears.

A drug-free option where few exist.

4 weeks
to significantly softer tinnitus

What they found

Forty-six older adults with chronic tinnitus were randomized to humming or a control group. The humming group reported significantly lower tinnitus loudness, annoyance, and handicap, plus reduced blood pressure and pulse. The control group showed no change.

Why it matters

Tinnitus has very few simple, side-effect-free tools. A practice you already carry with you, quieting the ringing and its grip on daily life, is a genuinely meaningful result.

46 adults
Participants
Randomized trial
Design
4 weeks
Duration
The bottom line
Less ringing, and less of its hold on the day.
The source
Ismail et al., 2022
PubMed
Study 06 Mood & sleep

Less anxiety,
better sleep.

Two weeks was enough to move both.

15 days
to lower anxiety and deeper sleep

What they found

Forty-two adults in home isolation practiced humming for just over two weeks. They showed significant reductions in depression, anxiety, and stress, with significant improvements in both sleep quality and overall quality of life. Note: this was a single-group study with no control arm.

Why it matters

Anxiety and poor sleep feed each other. Moving both, quickly, with a single simple practice, is exactly the kind of compounding effect that makes a habit worth keeping. The authors note it should be confirmed in a larger controlled trial.

42 adults
Participants
Single-group trial
Design
15 days
Duration
The bottom line
Calmer days and better nights, in two weeks.
The source
Jagadeesan et al., 2022
PubMed

The six studies above are standout findings from a review of 46 experimental studies with 3,097 total participants: Chetry et al., "Exploring the health benefits of bhramari pranayama (humming bee breathing): A comprehensive literature review," Indian Journal of Physiology and Pharmacology, 2024;68:71–85. Read the full review.

Foundational reading

Where the mechanism comes from.

The six studies above show what humming does. These are the papers that explain why. The underlying nervous-system biology HOOM is built on.

HOOM is a wellness tool, not a medical device. These studies describe humming practices generally; individual results vary. If you're managing a diagnosed condition, please loop in your clinician.

The science is real.
Feel it for yourself.

Sixty seconds. One hum. A different nervous system.