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Diet and food › Red Meat, Cancer and the Heart › Studies

Population study: followed a group

In 29,682 US adults, processed and red meat were linked to more heart disease

Zhong and colleagues · JAMA internal medicine · 2020

Original title: Associations of Processed Meat, Unprocessed Red Meat, Poultry, or Fish Intake With Incident Cardiovascular Disease and All-Cause Mortality.

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

Heart disease risk was higher with processed meat (adjusted HR, 1.07 [95% CI, 1.04-1.11]) and unprocessed red meat (adjusted HR, 1.03 [95% CI, 1.01-1.06]). Death from any cause was also higher (HR, 1.03 for each). Fish showed no link.

The study at a glance

Type of study
Population study: followed a group
Who or what was studied
29,682 people · US adults from 6 long-term studies followed about 19 years
What was tested
Each extra 2 servings a week of processed meat, unprocessed red meat, poultry or fish
What it measured
The question itself: cancer, heart disease and death
Who has a stake
No stake declared
One author had a small consulting fee from a drug company, unrelated to meat.
Journal
JAMA internal medicine, 2020
Source
PubMed record 32011623. 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: 29,682 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 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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