Omega-3 studies support heart health benefits, dismiss prostate concerns
A potentially negative effect of omega-3s on prostate cancer risk were raised in a controversial 2013 paper published in the Journal of the National Cancer Institute, which reported that high blood concentrations of long chain omega-3s led to a 71% higher risk of developing high-grade prostate cancer.
But a new study challenges those associations and supports the safety of the popular supplements. Scientists from the Intermountain Healthcare Heart Institute reported that higher levels of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) were not linked with elevated prostate cancer risk.
“DHA and EPA levels were not found to be positively related to PrCA [prostate cancer] risk; rather, findings suggest protective potential. These results are in keeping with recent randomized trials of omega-3 supplementation (VITAL, REDUCE-IT), which did not note increased cancer or non-CV death risk,” wrote researchers led by Viet Le, MPAS, PA, researcher and physician assistant at the Intermountain Healthcare Heart Institute in their abstract.
Commenting independently on the study’s findings, Harry Rice, PhD, VP of regulatory & scientific affairs for the Global Organization for EPA and DHA Omega-3s (GOED), told us: “This research corroborates a large body of scientific evidence NOT supporting the conclusions from Dr. Brasky et al.'s 2013 infamous publication implicating EPA and DHA in prostate tumorigenesis.
“It's worth noting that a 2014 publication co-authored by Dr. Brasky concluded that, ‘There was no strong evidence that circulating fatty acids are important predictors of prostate cancer risk’.”
Heart benefits supported, too
Le and his co-workers also reported findings from a second study at the AHA Scientific Sessions, which looked at 894 patients undergoing coronary angiography (a test that shows how blood flows through the arteries in the heart).
While the study subjects had no prior history of heart attack or coronary artery disease, about 40% of those patients had severe disease and about 10% had three-vessel disease upon their first angiogram. Plasma levels of omega-3 metabolites, including DHA and EPA, are also assessed, and the people followed to see who had subsequent heart attack, stroke, heart failure, or who died.
The data indicated that patients who higher rates of omega-3 metabolites had lower risk of those follow-up adverse effects regardless of whether they had severe disease or not on their initial angiogram.
“This study is important because we looked at how omega-3 helps patients who have already developed disease, and its effects on survival - both in getting to the first angiography to be diagnosed (vs. having a heart attack or worse before even knowing they have heart disease) and thereafter,” said Le.
“While a seeming association between higher plasma omega-3 levels and the findings of severe heart disease upon initial angiogram might raise alarms that omega-3 isn't beneficial, they did live to see a doctor and get diagnosed,” added Le. “And we saw a link between higher levels of omega-3 and their survival rate thereafter.”
Cardiovascular health
The study adds to a large body of evidence supporting the potential cardiovascular benefits of omega-3s, first reported in by Dr Jorn Dyerberg and his co-workers in landmark papers in the The Lancet in 1971 The American Journal of Clinical Nutrition in 1975.
For his groundbreaking contributions to nutritional science, Dr Dyerberg received the “Living Legend Award” from the International Union of Nutrition Scientists (IUNS) in 2013.
To date, the polyunsaturated fatty acids (PUFAs) have been linked to a range of cardiovascular benefits, from improving in blood lipid levels to reducing the tendency of thrombosis, and from improving blood pressure and heart rate to reducing the risk of coronary heart disease (CHD) and cardiac death.
Sources:
2019 American Heart Association Scientific Sessions
Session EP.APS.19 - Nutrition and Nutritional Biomarkers: November 17, 2019, 3:00 PM - 3:30 PM
Su3116 / 3116 – “Does Supplementation to Higher Plasma Omega-3 Levels Predispose to Prostate Cancer? Results From the Intermountain INSPIRE Biobank Registry”
Authors: V.T. Le et al.
2019 American Heart Association Scientific Sessions
Session EP.APS.19 - Nutrition and Nutritional Biomarkers: November 17, 2019, 3:00 PM - 3:30 PM
Su3113 / 3113 – “Higher Plasma EPA, EPA/AA and DHA Levels Are Associated With Lower Incident MACE Both in Those With and Without Angiographic CAD”
Authors: V.T. Le et al.