But as soon as you start looking into the job hormones play in controlling the functions our bodies perform, you can understand a little more about why an imbalance can have such a profound effect.
Please be aware that I am not a physician, and the following information is cobbled together from books and websites I have discovered. It's fascinating for me to learn about these things and I would like to pass my limited knowledge on- but it is just that- limited knowledge!
When my doctor told me I had an elevated level of prolactin, I was baffled, and if I'm honest, a little bit grossed-out. All I could think was 'but that's the one that produces breast milk! I'm not producing breast milk!' Why would my body be doing that? Producing too much of a hormone that women only use to feed a baby they'd just given birth to; when babies were so far from my reality at the time?
But here's the thing- there's more to it than that!
Some interesting facts about prolactin:
- its best known role is in lactation, but it also has other jobs, for example, it was helping to control water and salt balance in fish millions of years before humans even arrived on the planet!
- it comes primarily from the pituitary gland in the brain, which is in turn controlled by the hypothalamus. A chemical called 'thyrotropin-releasing hormone' stimulates its production, while dopamine inhibits it *see below*
- it is also produced in the uterus, breasts, white blood cells, and (in men) the prostate
- prolactin is an important regulator of the immune system
- it is important for controlling cell growth and death, and helps to keep blood healthy, form new blood vessels, and regulate blood clotting
- prolactin has been found to have effects on a person's brain and behaviour
- high prolactin levels have been linked to mental health issues
- it is responisble for feelings of sexual gratification, but increased levels are also linked with impotence and loss of libido
- stimulation of prolactin in turn inhibits production of another hormone called gonadotropin-releasing hormone. This is the hormone responsible for the release of FSH and LH, which you might remember from my post titled The Monthly Cycle. These hormones play a key role in the cycle of fertility: telling the ovaries to produce and release the egg. So if they are being inhibited, the cycle will obviously be affected and ovulation may not take place.
- levels of prolactin vary over the course of a day, as well as over the course of the menstrual cycle. It even varies depending on the seasons! Levels peak during REM sleep and in the early morning, and can also rise after food, excercise and sex.
- while the hormone estrogen stimulates prolactin during pregnancy, the combination of estrogen and progesterone also stop it from telling the body to produce breast milk. It is only when estrogen and progesterone suddenly drop while prolactin remains high, that milk is produced.
- a very high level of prolactin is one of the most common results of a tumor on the pituitary gland
- prolactin is a peptide hormone *see below*: a type of protein which is formed from amino acids and released into the bloodstream once the correct signals are given
- prolactin secretion is regulated by something called vasoactive intestinal peptide *see below*, which also keeps the digestive system funcioning smoothly, and inhibits gastric acid. Interestingly this is produced in the hypothalamus, as well as many other area of the body (spine, gut and pancreas)
This is the only other hormone I was tested for that was above the average level for a woman my age. Firstly- yes, women DO have testosterone in their bodies- it is not just a male hormone. The difference is that while women have a higher level of estrogen, men have a higher level of testosterone: hence estrogen being seen as the 'woman's' hormone and testosterone as the 'man's.'
Some interesting facts about testosterone:
- there is no 'cure' for an increased level of testosterone
- a high level of testosterone in a woman's body is often linked with polycystic ovary syndrome (where, instead of eggs forming and being released, the follicles form cysts)
- excess testosterone is often the cause of hirtuitism (excess body hair) in women. Some women can grow dark hairs on their faces, arms and armpits, back, chest, stomach and legs.
- other symptoms of a high level of testosterone are: acne, an enlarged clitoris, increased muscle mass, weight gain, thinning hair, irregular periods and deepening of voice
- testosterone is produced in the ovaries and in the adrenal glands (which are controlled by our old friend the pituitary gland)
- it is a steroid hormone, made from cholesterol
- it helps to build muscle and burn fat, and contributes to bone strength
- testosterone increases sex drive. Women with excess testosterone often have a higher than average sex drive
- testosterone is a growth hormone, and is partly responsible for the growth, maintainance and repair of reproductive tissues
- women are more sensitive to the hormone than men, and require less to be affected by it
- interestingly, when a man and a woman enter into a loving relationship, the man's testosterone levels fall while the woman's rise! Apparently this only lasts as long at the 'honeymoon' phase, and has been theorised to be linked with the fact that couples tend to mimic each other's behaviour in the early days of a relationship. Testosterone levels in men also fall when they become fathers. Research has also suggested (sorry guys you might not like this one...) that men with higher levels of testosterone are less likely to get married or enter into committed relationships. They are also more likely to divorce, and more likely to have affairs
- testosterone can affect behaviour: higher levels of testosterone lead to more aggressive, assertive and spontaneous/risk taking behaviour. It has also been linked to depression, moodiness and irritability
- apparently elevated levels of testosterone are more common in city-dwelling women with hectic work schedules, and it can also be triggered by: a high sugar and carbohydrate diet, poor liver function, low sex hormone binding globulin, insulin resistance and poor thyroid function
Interestingly, decreased levels of dopamine have been linked to 'restless legs sydrome'. This is a condition where the sufferer feels the irresistable urge to move body parts (usually the legs) to relieve an uncomfortable feeling. Moving or stretching offers temporary relief but the feeling returns. I often suffer from this, but would never have guessed it could be linked to a hormone imbalance until now!
Decreased dopamine levels are also connected with ADHD.
Dopamine has important functions throughout the body: blood, digestion, processing toxins, motor control, motivation, arousal, feelings of reward/satisfaction/happiness, sexual gratification and nausea
If you have too much of this hormone, it will inhibit the production of dopamine. So, you can see how this has a knock-on effect on the production of prolactin, since TRH stimulates its production, and dopamine decreases it.
Vasoactive intestinal peptide
In the brain, VIP helps to control the body's daily timekeeping. I find this particularly interesting, since my body clock so oftens seems to behave strangely- keeping me awake all night, or causing me to feel sleepy at three in the afternoon. Of course, this may simply be caused by other factors such as stress and exhaustion... but since there is a link here, I think it may likely be a combination of many factors.
An interesting link between two apparently separate body systems is that both VIP and prolactin are peptide hormones. Peptides are produced in the digestive system when an enzyme called pepsin is released in the stomach. Pepsin degrades food into proteins, amino acids and peptides, all of which are essential components in the production of hormones in the brain. Healthy digestion = healthy brain = healthy reproductive system!