Hormones have gotten a bad rep these days, but they’re not the bad guys. Sure they can cause your mood to change quicker than the speed of light, but you wouldn’t be here if it weren’t for them!
Hormones are chemical messengers that regulate almost every activity in your body. Before hormones can bark an order, they have to latch onto an appropriate receptor site. Hormone receptor sites are like little parking garages built onto cells. Once the hormone parks itself into a receptor site, it’s free to enter the cell and tell the cell what to do.
As far as your breasts are concerned, there are four hormones that matter most: estrogen, progesterone, prolactin, and growth hormone. These hormones command your breasts to grow.
Ah, estrogen. Without it I guess we’d be all walking around with hot flashes all day! Estrogen is also the hormone most responsible for breast growth.
Actually, estrogen is not a single substance. There are sixty hormones with estrogenic properties swirling through your body at this very moment! The three main estrogen hormones include: estradiol, estrone, and estriol. Estradiol is the strongest and is the hormone that is responsible for breast development. Estrone is a weaker estrogen produced in the fatty tissue of both males and females. Estriol is the weakest of the three and is made in the body from other estrogens.
Testosterone can also be converted into estrogen, which is why you often hear steroid-pumped bodybuilders complaining about “bitch tits,” one of the side effects of excess testosterone. This conversion process is called aromatase and takes place in your body’s fat cells.
Progesterone is another important breast enlarging hormone that is specifically involved in the formation of the glands. It works alongside estrogen to keep the female system humming along happily.
While genetic females begin secreting progesterone at the onset of menstruation, males also produce a small amount of progesterone in the adrenal glands. In women, progesterone levels rise and fall with the menstrual cycle.
Prolactin is a hormone that is involved in both breast development and milk production. Males are as capable of producing prolactin as females are.
During puberty, prolactin works with estrogen and progesterone to develop the mammary glands, while increasing the number of estrogen receptors in the breasts. Prolactin also causes the breasts to store fat by increasing the production of lipoprotein lipase (LPL) in your breasts.3 LPL is a “fat storage” enzyme.
Prolactin controls milk production in genetic females and plays an important role in maintaining the immune system for all of us. It is produced by the pituitary glands and can also be stimulated via extensive stimulation. This stimulation usually comes in the form of a suckling baby, but any form of regular stimulation to the breasts and nipples is enough to trigger it!
Normally, prolactin is inhibited by a “prolactin inhibiting factor” (PIF), known as the brain chemical, dopamine. You’ve probably heard of dopamine before. Besides suppressing prolactin, this chemical is connected to emotions and addictions. Nicotine, cocaine, and other stimulants produce feelings of euphoria by increasing dopamine levels in your brain. But be warned: these drugs are no good for the boobies!
Growth hormone, as the name implies, triggers the growth of your body. It also plays a special role in breast development. Growth hormone is so important that it is one of your body's most plentiful hormones. It is produced by the pituitary gland during the first two hours of sleep. Almost immediately after it’s secreted, growth hormone is converted in the liver into a new, more usable substance known as Insulin like Growth Factor (IGF).
Growth hormone could be thought of as your body’s “Master Hormone” since it regulates every other hormone you’ve got. Growth hormone is produced in massive amounts during puberty, promoting the growth of cells, tissues, and organs. Without enough growth hormone, your body simply wouldn’t grow.
As an adult, growth hormone is involved in tissue repair and cell replacement. Unfortunately, growth hormone levels start to plummet after the age of thirty. By the time you hit sixty, your growth hormone level could be 75% lower than it was when you were twenty! Low growth hormone levels are directly responsible for the aging of the body.