The Pineal Gland, also known as the epiphysis cerebri, or the Third Eye in some ideologies, is a small endocrine gland found in the center of the brain. The shape of the gland kind of looks like a pine cone, which is where its name comes from. It is only about the size of a grain of rice, but it serve a very important function in the body.
The main function that the pineal gland is to produce a hormone named Melatonin. Melatonin, when secreted, helps to stimulate day-night cycles in the brain, and help you get your circadian rhythm in check. This means that it helps you to get tired and fall asleep at the right times. The production of this hormone is stimulated by how light or dark it is, more melatonin when it is dark, less when it is lighter. This is why it is important not to use cellphones and be next to a bright screen too soon before bed.
It is also believed that secretions of melanin by the pineal gland can help to prevent oxidative stress. The effect does not seem to be large, but it is significant. Some studies have shown that the hormones produced by the gland are even able to protect against neurodegeneration. Information has also shown that by removing the pineal gland, mice has been found to be less able to reproduce, as it acts on other sex hormones in the body.
More and more information to date is being learned about the pineal gland and the effects that the hormones secreted by it can have on health and wellness. More research should be done, however, on the specifics.