There are a select few truly selfless individuals that put others interests above their own.
Perhaps my perspective is overly pedantic, or I'm making distinctions that have no practical value... but I would frame any ostensibly altruistic behavior as still meeting a personal need. For example, a person who sacrifices their life to save another, they do so to get something they consider more valuable than their physical life- whether it is to leave a legacy and retain their identity as a person with certain values, and be posthumously appreciated (which might provide some immediate succor or redemption), or perhaps it might be to honor a person whom they feel has more to offer the world, or perhaps to honor an idea about how we are supposed to behave to make the world a better place.
Maybe there is no practical importance for distinguishing whether you do something for reason XYZ despite the apparent personal cost, or whether you do it because it satisfies some personal physical/intellectual/emotional/spiritual need. Depending on how deep you like to examine things, the outward result might be sufficiently explanatory.
I do think the distinctions are important because they give us greater insight to the human psyche, and build a higher resolution picture of what drives people, how we manipulate and are manipulated in causes small and large, and how we can make sense of sometimes seemingly senseless and contradictory behavior. I believe it is also the breadcrumb trail we can all follow to unravel why we sometimes do things that appear to not be in our own interest, and why it can be difficult to break habits that seem to not benefit us. The key is to look deeply into ways in which the habits ARE in our interest, how they give us something we want in the moment (or reaffirm a story we like to tell ourselves to hold on to pleasure or to block pain), despite some other part of ourselves that recognizes how the habit is not good for us in a bigger picture.