If you need eye drops for dry eyes â known as artificial tears â choose a brand without the preservative benzalkonium chloride, which can cause irritation, says Andrew Lotery, professor of ophthalmology at the University of Southampton. âYou tend to find it in eye drops that come in bottles,â he says.
Endorphins are natural opium-like hormones that are produced by the pituitary gland and the hypothalamus of your body. Endorphins act on your brain's opiate receptors to block their ability to receive pain messages from the sensory nerves. This makes you less sensitive to pain. Endorphins also work on your emotions.
Sebum, secreted by the sebaceous gland in humans, is primarily composed of triglycerides (~41%), wax esters (~26%), squalene (~12%), and free fatty acids (~16%). The composition of sebum varies across species. Wax esters, like squalene, are unique to sebum and not produced anywhere else in the body.ebum, secreted by the sebaceous gland in humans, is primarily composed of triglycerides (~41%), wax esters (~26%), squalene (~12%), and free fatty acids (~16%). The composition of sebum varies across species. Wax esters, like squalene, are unique to sebum and not produced anywhere else in the body.