Important breaks I do take: Coffee walk (unfortunately on some busy days I simply can't make it out), Quick chats with the team, and Pomodoro-timed walks to stretch/ease the mind.
I usually eat lunch at my desk, which annoys me, because I always want to socialize and be better at that. I don't find it easy to do this since the days are so busy.
I'm a product manager, so I spend much of my days in meetings that are a mix of working sessions, scoping exercises, communications with external clients, and team-focused meetings.
On the days I don't have any meetings (they do exist), I zone out and get some work done. Lately I've been focusing on the DevOps for our team.