Higher EPA plus DHA Intakes and Protection from Cardiac Mortality Found in Spanish Population Study
Sala-Vila, A. et al., Journal of the American Heart Association, in press, 2016
Lipid Clinic, Dept. of Endocrinology and Nutrition , Institut d’Investigacions Biomediques, Barcelona, Spain plus other centers in Spain and the US (Harvard School of Public Health, Boston, MA.)
The present population investigation was designed to determine if failing to meet dietary targets for short-chain (alpha-linolenic acid, LNA, intakes from mainly plant sources) and long-chain omega-3 fatty acid intakes (as EPA/DHA mainly from fish/seafood sources) may affect the risks for cardiac and all-cause mortality. The minimal dietary targets for omega-3 fatty acid intakes were based on recommendations released in 2004 by ISSFAL (International Society for the Study of Fatty Acids and Lipids) of 500 mg/day as EPA/DHA for primary cardiovascular disease prevention and 0.7 % of energy as LNA for a healthy intake. (Dr. Holub has determined that 0.7 % of energy as LNA would be the equivalent of 1.74 grams LNA/day based on the average energy intake of all subjects in the present report being 2235 calories/day). In this study, 7202 participants (both genders, average age of 67 years) in Spain (a country with a high fish consumption) were followed for 5.9 years. The subjects were determined to be free of prior cardiovascular disease at the beginning of the study. Dietary intakes of LNA and EPA/DHA were assessed via a validated food-frequency questionnaire (following face-to-face interviews) along with nutrient and fatty acid content values of the diverse foods so as to determine intakes of the various omega-3 fatty acids. The end point monitoring of the subjects included all-cause mortality and mortality from cardiovascular disease including fatal coronary heart disease, sudden cardiac death, and fatal stroke.
As compared to those not meeting the recommended target set by ISSFAL of 500 mg EPA plus DHA daily, those who met such a target exhibited a significantly lower risk for fatal cardiovascular disease (by 39 %) and for fatal coronary heart disease (by 46 %). It was determined that 76 % of all the subjects met the ISSFAL recommendation and the average intake for the whole population was 840 mg of EPA plus DHA/day. In the case of LNA, those who met the recommended intake of 0.7 % of energy had a 28 % lower risk of total mortality as compared to those not meeting the ISSFAL target. It was estimated that 22 % of the population met the recommended LNA intake and the average intake for the whole population was 1.4 grams/day. (Dr. Holub notes that the latter represents 0.6 % of dietary energy intake and not 0.06 % as reported in Table 3 of this research paper). The authors found that the highest and most significant reductions in the risk of all-cause mortality (by 37 % overall) were in those participants who fulfilled the ISSFAL recommendations for both LNA and EPA/DHA intakes.
Dr. Holub's Comments:
The present findings support the concept that higher intakes of dietary long-chain omega-3 fatty acids as EPA plus DHA in addition to LNA can act synergistically in reducing all-cause mortality while only higher EPA/DHA intakes exhibited significant reductions of fatal cardiovascular disease and fatal coronary heart disease. Interestingly, the average intake of LNA as found in this population from Spain (1.4 grams/day) is similar to reported intakes per person in North America and many other countries. However, the average intake of EPA plus DHA of 840 mg/day in this Spanish population was dramatically higher than found in North America where average intakes range from only 110-150 mg/day. Whereas 76 % of the Spanish participants met the recommended ISSFAL target for daily EPA/DHA intake (due to their high intake of fish/seafood), only a small minority of the North American population would do so.