First you must learn how the human body works in general, and what’s expected of it. Then you learn what your body can do, and its exceptions and variations. Then you’re often forced to understand how the body of those you love and support works differently. Few of us have a body that doesn’t come with quirks that split us away from being ‘average’, which becomes specially true as you age, because it changes again. What you could once do or eat is suddenly — and sometimes, dramatically — different.