It's said that (for those of us with full visual faculties) we process something like 80% of what we learn visually. Color-coding, shading and graphs are some ways of marking differences between between values and degrees of value, helping us digest large amounts of complex information in a single glance. Consider the political map, with each country, state, county, or other subdivision in a different color. "Red" states and "blue" states. Degrees of obesity per state. And so on.
Consider the color-coded diagram of the human digestive system. Red stomach, yellow intestines, pink colon, green gallbladder, brown liver. What color is your pancreas? Do you want to color it in World Diabetes Day blue to indicate yours has died?
Color-by-number and paint-by-number puzzles show us simplified recreations of Old Masters. Color by number charts show us the trends in our blood glucose levels, A1cs, and so on as well.
Most glucometer software I've seen color codes blood glucose readings: very low, low, target, high, very high. You can set the levels on the meter or in the software, and you may be able to change the colors on the graph, but you will see line graphs poking in and out of bars of different colors, colored bar charts, or colored pie charts, depending on the software and the analysis you've chosen.
Even Excel color-codes data if you set up conditional formatting to show how well you are doing with respect to your health goals.
Still, the truth is more subtly shaded than the block colors of our meter software. Being within 1-2% of a narrow "goal" range does not mean you "failed" to care for yourself; it means that for some reason, something is a little bit "off". Or that your health requires a different set of goals than the meter companies envisioned. Rather than the stark contrast between red and green, or red and yellow, perhaps one's readings should be shown more of a shading from cold blue through warm red, from ultraviolet through the visible range into the infrared.
Yet for those of us trying to make sense of our numbers, the clear boundaries and delineations keep us from seeing "more yellow" as "more blue" and a high reading as a low one.
