Sweep a tablespoon over the entire surface of your tongue.
Place the spoon in a clear bag and zip. Put it under the bright light close enough to let the spoon feel the warmth of the light bulb but not too close to make it hot. Check the spoon after 1 minute.
A clean, streak-free, odor-free spoon - no health problems.
Is there a smell?
If it is putrid and harsh, you have stomach or lung problems.
Sweet - you may have diabetes.
Smell of ammonia - kidney problems.
White or yellow - a problem with the thyroid glands.
White color can also indicate respiratory infections.
Purple - bronchitis, poor blood circulation, high cholesterol.
Orange - kidney disease.