Inside every healthy cell is a simple, powerful process that keeps you alive: oxygen in, nutrients in, energy made. You breathe, oxygen enters the bloodstream, and it’s delivered to tissues like the breast. You eat, nutrients are broken down, and cells bring in what they need through specialized “doors” in the cell membrane. Then the real work begins inside the cell. Tiny structures called mitochondria act like energy factories, converting oxygen and nutrients into usable energy that powers repa