Need to read the full study and even than although omega 3 intake has other health benefits it would be short sighted for anyone to have ever thought that by supplementing with omega 3s (EPA/DHA) that it would protect one from having a stroke or heart attack as there are way too many other factors involved regarding cardiovascular disease.
Ones genetics, lifestyle, diet, quality of sleep, levels of stress, obesity, underlying health issues, environmental toxins.....the list goes on!