One should also take regular blood tests, at least yearly, to keep track of certain health markers that you wouldn't want outside reference ranges. Some examples would be vitamin D (VERY common to be deficient in vit D), HDL, LDL, iron, electrocytes and markers directly related to organ functions. Blood pressure is also a very big one that a lot of people take for granted. There are so many things that affect blood pressure both positively and negatively, so one should really keep an eye on it.