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Randomized trial · measured lab tests or safety

4-week trial in 40 people with heart failure: sauna lowered a heart strain marker

Fujita and colleagues · Circulation journal · 2011

Original title: Effect of Waon therapy on oxidative stress in chronic heart failure.

Under review. A person has not yet checked this summary against the paper. It is written from the PubMed abstract. Until a person checks it, search engines are asked not to list this page.

What the study found

Points to benefit

BNP fell from 402±221 to 225±137pg/ml (P<0.001) in the sauna group and did not change in controls. Hydroperoxide, a stress marker, fell from 422±116 to 327±88U.CARR. Hamster tests found less heart stress too.

The study at a glance

Type of study
Randomized trial
Who or what was studied
40 people · people with chronic heart failure, plus heart-disease hamsters
What was tested
Daily far infrared dry sauna at 60°C for 4 weeks vs usual care alone
What it measured
Lab tests or markers
How long
4 weeks
Who has a stake
No disclosure in PubMed
No disclosure in PubMed.
Journal
Circulation journal, 2011
Source
PubMed record 21173495. This page is based on the abstract only.

How much this study counts

  • ✓Randomized: people were put into groups by chance, so the groups start out alike.
  • –Small: 40 people. Small trials can miss real effects or find chance ones.
  • –Short: 4 weeks. Longer-term effects are unknown.
  • –Measured lab tests or markers, which stand in for heart disease, blood pressure and death. A better marker does not always mean better health.
  • •The PubMed record has no conflict-of-interest statement.
  • •Summarized from the PubMed abstract only. The full paper may hold details the abstract leaves out.

✓ Strength– Limit• Note

These points come from fixed rules about the type of study, its size and length, what it measured, and who has a stake. Every study on Digestery gets the same rules.

Where this study sits

Each dot is one on-topic paper on this question. Steps near the top answer the question more directly.

↑ Stronger evidence

  1. Trials in people: heart disease, blood pressure and death

    3

    3 benefit

  2. Trials in people: other measures

    2

    1 benefit, 1 no difference

  3. Trials in people: lab tests or safety

    5

    2 benefit, 1 mixed, 2 no difference

    ↑ This study is the ringed dot

  4. Population studies

    4

    4 benefit

  5. Blood levels and genes

    0

    None among the papers we read.

↓ Weaker evidence

  • Points to benefit
  • Mixed
  • No difference
  • No direction
  • Points to harm

How it fits with the other research

The short answer to “Does sauna use lower heart disease risk?”

Possibly, but not proven in trials.

Confidence: low. Based on 21 on-topic papers.

Read the full answer

Of the other 4 papers on the same step: 1 benefit, 1 mixed, 2 no difference. This one found benefit.

Other papers on the same step

See all 21 studies on this question

How this page was made

Label

First read of the abstract
Claude Sonnet
Independent second read
Claude Haiku
Differences settled
The two reads differed. The reviewer checked the abstract and kept the first read. Claude Opus 5.5.
Headline
Claude Sonnet, from the checked study record. A script checked its numbers and wording.
Numbers
Checked against the abstract by a script
“How much this study counts”
Fixed rules, the same for every study
Source check by a person
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