Is it possible to test your nutrient levels by tasting your blood?

I cut my finger on broken glass and licked it to try and encourage it to stop bleeding. The thought came to me, as it often does at times like this: blood tastes different at different times. Is there some way of gauging your blood composition by taste? Sometimes it is saltier, sometimes it tastes more of iron, sometimes it is more watery. It would be great to be able to interpret that somehow.

I cut my finger while preparing breakfast, having eaten nothing for the past 12 hours, so it's little surprise that the blood tasted mostly like water with a hint of iron: there was nothing in my system at that point. I'd love to be able to draw more nuanced conclusions about my health this way - like, knowing whether I needed to reduce or increase my salt intake, or whether I had high or low white blood cells, etc. The only thing is, most of sites about 'tasting blood' are dedicated to vampirism, and that's really not my jam. Your thoughts...?