A tiny fingerprint can reveal a plethora of information.
Besides age, a fingerprint can also determine if someone smokes, has taken medication or consumed alcohol recently, and even what cosmetics they use.
This is because a fingerprint is composed of substances formed by sweat and oils secreted from the sweat and sebaceous glands on the fingers.
These components are 98% water, plus various trace elements such as amino acids, iron, magnesium, zinc, and urea.
It is precisely these minute components that can expose relevant information about different individuals.
People with different lifestyles have subtle differences in the chemical substances in their sweat and oils.
For example, people with a strong taste for salty foods will have a higher sodium ion content in the residue of their fingerprints.
Of course, because fingerprints are inherently small, the amount of residual material is measured in milligrams or micrograms.
