Here is a summary of the results:
- In observational studies that measured diet, only trans fat was related to cardiovascular risk. Saturated, monounsaturated, and polyunsaturated fats were unrelated to risk.
- In observational studies that measured circulating concentrations of fatty acids, long-chain polyunsaturated fatty acids (DHA, DPA, EPA, AA) were associated with lower risk. The dairy-fat-derived margaric acid (17:0) was also associated with lower risk. No other fatty acids were related to risk, including trans fatty acids.
- In controlled trials, supplementation with omega-3 or omega-6 fatty acids did not alter risk.
In conclusion, the pattern of findings from this analysis did not yield clearly supportive evidence for current cardiovascular guidelines that encourage high consumption of polyunsaturated fatty acids and low consumption of saturated fats. Nutritional guidelines on fatty acids and cardiovascular guidelines may require reappraisal to reflect the current evidence.