Population study: followed a group

In 71,264 Korean women, processed meat was linked to higher breast cancer risk

Lee and colleagues · Clinical nutrition (Edinburgh, Scotland) · 2025

Original title: Meat intake and breast cancer risk from the Health Examinees study.

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 harm

One or more servings of processed meat a week went with 57 % higher breast cancer risk (HR = 1.57, 95 % CI: 1.09-2.27). Beef went with lower risk (HR = 0.82, 95 % CI: 0.67-1.01), a range that touches 1.

The study at a glance

Type of study
Population study: followed a group
Who or what was studied
71,264 people · Korean women aged 40 to 69; 713 got breast cancer
What was tested
Eating processed meat, beef and other meat vs none
What it measured
The question itself: cancer, heart disease and death
Who has a stake
No stake declared
No competing interests declared.
Journal
Clinical nutrition (Edinburgh, Scotland), 2025
Source
PubMed record 40902216. This page is based on the abstract only.

How much this study counts

  • –Shows a link, not a cause: people chose their own habits, and other differences between them may explain the result.
  • ✓Followed people over time, so habits were recorded before the outcome happened.
  • ✓Large: 71,264 people.
  • ✓Measured the question itself: cancer, heart disease and death.
  • ✓No competing interests declared.
  • •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: cancer and heart disease

    0

    Not done yet. This is the step that would answer the question.

  2. Trials in people: other measures

    0

    None among the papers we read.

  3. Trials in people: lab tests or safety

    6

    2 benefit, 4 harm

  4. Population studies

    12

    1 benefit, 2 mixed, 1 no difference, 8 harm

    ↑ This study is the ringed dot
  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 red meat raise cancer and heart disease risk?”

Linked to higher risk, especially processed meat.

Confidence: low. Based on 30 on-topic papers.

Read the full answer

Of the other 11 papers on the same step: 1 benefit, 2 mixed, 1 no difference, 7 harm. This one found harm. It agrees with most of them.

Other papers on the same step

See all 30 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 reviewer corrected 1 field after reading the abstract. 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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