Types of tears
1. Basal tears
These are your basic tears. Your eyes roll around in them all day. They contain oil, mucus, water and salt, and help fight infection. The oil keeps your tears in place and prevents them from evaporating into the atmosphere. Blinking spreads them evenly over the surface of your eye. These tears can improve your vision and sharpen your focus.
2. Irritant tears
These are your eyewash tears. The glands under your eyebrows push them out when you peel an onion, vomit or get dust in your eye. They flush out the material that’s irritating your eyes. These are the kind of tears that stream down your face when your allergies are kicking into high gear.
3. Psychic or emotional tears
These tears gush in response to strong emotions like sadness, grief, joy or rage. They have the same chemical makeup as basal tears, but contain more stress hormones and natural painkillers. Humans and animals have compounds in our body fluids that give off subtle messages to other members of the species. That’s why sometimes our tears can relay chemical messages (either intended or unintended) to someone close by. This can bring about empathy or compassion in other people, or signal them to stay away, for example.