Association of Dietary, Circulating, and Supplement Fatty Acids With Coronary Risk A Systematic Review and Meta-analysis Chowdhury et al, 2014, Ann Int Med

(Quick) paper summary Aim: Associations between fatty acids and coronary disease Method: Meta-analysis of prospective trials Dietary FA intake Biomarkers of plasma FAs Intervention (supplementation) trials Results (later) Conclusions: ”Evidence does not clearly support CV guidelines that encourage high consumption of polyunsaturated FAs, and low consumption of total SFAs”

Media interpretation of the paper

Media dramatization of the paper

Scientist backlash? Complaints Controversy Calls (for retraction): Not universal…..

Resolution to the 3-way

Proposed resolution 1. Consider the history of the paper 2. Read the results 3. Consider the methodology What was done What was not done 4.Consider the original studies 5.Consider other research

1. History of the paper

2. Read the results (now there is a novelty).

2. Read the results Plasma SFAs

2. Read the results Plasma MUFAs

2. Read the results Plasma PUFAs (ω-3) (remember – EVERYTHING we knew about diet was wrong).

2. Read the results Plasma PUFAs (ω-6)

2. Read the results Intervention (supplementation) trials

2. Read the results Self-reported habitual intake of total SFA not associated with cardiac events Self-reported habitual intake of total MUFA not associated with cardiac events Self-reported habitual intake of α-linolenic not associated with cardiac events Self-reported habitual intake of LC ω-3 protective Self-reported habitual intake of Total ω -6 not associated with cardiac events Total trans fat associated

2. Read the results Plasma SFAs: only 17:0 protective. 14:0; 15:0, 16:0, 15:0, 18:0 not associated Total MUFA not associated All LC ω-3 strongly protective individually No evidence that total LC ω -3 associated Protective effect of ARA, no association with other ω-6

2. Read the results Intervention trials showed no effect of supplementation for α-linolenic, total LC ω- 6, or ω-6

My first conclusions Different FAs have different associations with outcomes Those most associated with a protective effect have not been measured in the diet, nor studied in interventions But, no evidence that total saturated fat (intake / plasma) associated with events Convincing evidence that some ω-3 protective, although this has not been studied in an intervention trial.

In defense of the authors: … do not clearly support.. guidelines that promote high consumption of ω-6 PUFA and … reduced consumption of SFA LC ω -3 PUFAs in primary prevention odd-chain SFAs (…milk or dairy consumption) may have less deleterious effects

3. Consider the methodology

The development of cardiac events

3. Consider the methodlogy

3. Consider the methodology Nutrient density substitution models convey information on dietary substitution; associations do not.

4. Consider the original samples Timeframe Participants & baseline characteristics Event rate was up to 42%

Acknowledgements Dariush Mozaffarian* Brian Steffen* American Heart Association* *The views expressed in this presentation are not necessarily the views of the organizations / individuals

Further discussion Is this an irresponsible paper? If so – who was irresponsible? Should we reconsider guidelines on saturated fat? Do YOU know what the guidelines are? What about other outcomes? The role of carbohydrates