You need a spoon and a plastic bag and on this way you can check is everything alright with your respiratory system, gut hormones, metabolism, kidney or teeth.
All you have to do is to scoop with the spoon little wet deposits from the surface of your tongue. While you do that, try deposits to be closer to your throat.
After that, wrap the spoon in a plastic bag and leave it to stand for 60 seconds under bright light bulb. The light from the bulb helps in the development of bacteria and as much as the bulb is stronger as much as the result will be more visible.
If you are healthy, the deposits will be clean. But if there are many and they are with strange color and unpleasant odor, it can be early sign of problems with lungs, liver, kidneys or hormones.
If you received result with strange color and unpleasant smell, for best, visit your doctor and do some exams for discovering what kind of health problem you have. This test also helps in discovering do you have bad breath, problem for which many people are not aware of.
In case you experience some fruity smell, it can indicate ketoacidosis or disorder of metabolism which can cause development of diabetes. If you experience an unpleasant odor which reminds of ammonia, it is possible for you to have kidney problems.
Do not panic immediately; the unpleasant odor is not always representing necessarily a sign of an illness. In fact, in most cases, it is about problems with tonsils, gums or decay.