31 May 2018 --- Eating higher amounts of protein was associated with a slightly elevated risk for heart failure in middle-aged men when compared to those who ate less protein, a study has found. The study, published in Circulation: Heart Failure, an American Heart Association (AHA) journal, adds to the little-researched area of how protein may impact heart failure risk. Researchers also suggest that the type of protein source may be significant, with processed meat being a less healthy protein source than fish, nuts or plant sources.