None of the studies said, 'Eat less fat to live longer' — in fact, some warned it might not help or could even be harmful.
Scientific Claim
The available randomized trials before 1983 did not conclude that reducing dietary fat would reduce mortality, and none provided evidence to support the implementation of national dietary guidelines.
Original Statement
“No RCT concluded that dietary guidelines should be introduced. ... Rose et al warned of possible harm by administering corn oil. The Research Committee concluded 'A low-fat diet has no place in the treatment of myocardial infarction.'”
Evidence Quality Assessment
Claim Status
appropriately stated
Study Design Support
Design supports claim
Appropriate Language Strength
definitive
Can make definitive causal claims
Assessment Explanation
This is a factual summary of trial authors’ own conclusions, directly cited in the text. The claim is precise and supported by primary source analysis.
Evidence from Studies
Supporting (1)
Evidence from randomised controlled trials did not support the introduction of dietary fat guidelines in 1977 and 1983: a systematic review and meta-analysis
Before 1983, scientists tested whether eating less fat would help people live longer, but the studies showed no real benefit—so the government made dietary rules without proof they worked.