Re:Eat Real Food
by fogzen on Wednesday January 07, 2026 @11:29PM
(#46537205)
According to ChatGPT, RCTs do show correlation between coronary events and saturated fat intake compared with PUFs. Can someone with expertise shed light on the research appendix justifications for excluding this research?
> Randomized controlled trials do not show a step-function threshold (e.g. “below X% energy from saturated fat, risk disappears”). Instead, they show:
• Progressive reductions in coronary events as saturated fat is lowered and replaced with polyunsaturated fat (PUFA).
• Risk reduction tracks the amount of replacement, not merely crossing a cutoff.
In other words:
risk ↓ smoothly as saturated fat ↓ (when replaced appropriately).
⸻
2. Magnitude of reduction seen in RCTs
Meta-analyses of classic RCTs (LA Veterans Study, Oslo Diet-Heart, Finnish Mental Hospital, etc.) show:
• ~2–3% absolute reduction in coronary events
• ~10–30% relative reduction
• Achieved when:
• Saturated fat is reduced from roughly 15–20% of total energy → ~8–10%
• And replaced primarily with PUFA, not refined carbohydrates
Key quantitative finding (Mozaffarian et al., PLOS Med 2010; Cochrane 2020):
For every 5% of energy replacement of saturated fat with PUFA → ~10% reduction in coronary events
⸻
3. Why guidelines converge on <10% (and often <7%)
Because RCTs didn’t test ultra-low saturated fat intakes (e.g. 2–3%), guideline thresholds are pragmatic extrapolations, not mechanistic breakpoints:
• <10% energy: roughly the lowest level consistently achieved in long-term RCTs
• <7% energy (AHA): extrapolated from LDL-cholesterol lowering and event reduction curves
These are policy targets, not RCT-defined thresholds.
> Randomized controlled trials do not show a step-function threshold (e.g. “below X% energy from saturated fat, risk disappears”). Instead, they show: • Progressive reductions in coronary events as saturated fat is lowered and replaced with polyunsaturated fat (PUFA). • Risk reduction tracks the amount of replacement, not merely crossing a cutoff.
In other words: risk ↓ smoothly as saturated fat ↓ (when replaced appropriately).
⸻
2. Magnitude of reduction seen in RCTs
Meta-analyses of classic RCTs (LA Veterans Study, Oslo Diet-Heart, Finnish Mental Hospital, etc.) show: • ~2–3% absolute reduction in coronary events • ~10–30% relative reduction • Achieved when: • Saturated fat is reduced from roughly 15–20% of total energy → ~8–10% • And replaced primarily with PUFA, not refined carbohydrates
Key quantitative finding (Mozaffarian et al., PLOS Med 2010; Cochrane 2020):
For every 5% of energy replacement of saturated fat with PUFA → ~10% reduction in coronary events
⸻
3. Why guidelines converge on <10% (and often <7%)
Because RCTs didn’t test ultra-low saturated fat intakes (e.g. 2–3%), guideline thresholds are pragmatic extrapolations, not mechanistic breakpoints: • <10% energy: roughly the lowest level consistently achieved in long-term RCTs • <7% energy (AHA): extrapolated from LDL-cholesterol lowering and event reduction curves
These are policy targets, not RCT-defined thresholds.