You can draw some conclusions by reading a lot of labels though. Two items that show up in a lot of personal products are glycerin and mineral oil. Both are thick clear oils. Mineral oil, which comes from petroleum, shows up everywhere. It is used to make lipstick shiney.
Mineral oil is used in skin moisturizers.
It seals your skin with a layer of oil so the moisture is trapped inside. It is used in hair conditioners where it coats the individual strands of hair. This does three things. It also makes your hair, just like your lips, shiney. Glycerin is another oil used similarly to mineral oil, but it is generally thicker in consistency.