Right now, as you’re reading this article, your body is hard at work. Without you even realizing it, your hair is growing, your bones are releasing minerals, and your metabolism is converting calories into usable energy. Meanwhile, your hypothalamus is taking in and responding to stimuli around you that might not even be aware of.
It’s rare that we take the time to think about how much goes on inside our bodies. We tend to take for granted the millions of little functions of our body, day in and day out, which keep us alive.
Aside from the automatic bodily functions that our hormones initiate, hormones can also influence our actions, behavior, mental health, and the way we see the world.
Hormones are organic chemical messengers that deliver instructions to the brain, using your bloodstream as a sort of ‘highway’, from glands called endocrine glands to your various organs, cells, and tissues, including your brain. You have several endocrine glands located throughout your body, including your adrenal glands (on your kidneys) sex glands (testes on men, ovaries on women), the thyroid gland in your neck, and, most importantly, the pituitary gland.
The pituitary gland is small, yet mighty. Roughly the size of a pea, it is located right at the base of your brain. In science, it is sometimes referred to as the ‘master gland’ because it controls the activity of other endocrine glands, in some cases prompting those glands to release their own hormones. The pituitary gland is split into two sections: the anterior pituitary and the posterior pituitary gland.
Our hormones regulate our bodies’ physiological functions and our brain’s response to stimuli. Additionally, they can affect our behavior and play a role in the way we express ourselves.
With so much importance placed on our hormones, it’s worth looking into where hormones come from and how they are controlled. Read on to find out about the functions of hormones in your body.
Why Are Hormones Important?
We know of over 50 different hormones in humans. Each and every hormone has a unique and fundamental role to play in carrying out the actions needed for our bodies to function. Every multicellular organism on earth, including plants, have hormones.
In humans, our hormones carry out the physiological functions that are vital for sustaining life. Some examples of the functions of hormones include reproduction, metabolic function, growth and repair of cells and tissues, stress management, and maintaining water and mineral levels.
We already know that the pituitary gland is our most important endocrine gland, but what hormones come from it? There are 8 hormones that the pituitary gland secretes, 6 of which are produced by the anterior pituitary, the remaining 2 are produced by the hypothalamus and stored in the posterior gland.
Of the 6 produced in the anterior pituitary, 4 control the functions of other glands, prompting them to release hormones of their own. They are adrenocorticotrophic hormone (ACTH) which prompts the adrenal glands to produce cortisol; thyroid-stimulating hormone (TSH) which triggers the release of thyroxin by the thyroid gland; and luteinizing hormone and follicle-stimulating hormone (LH and FSH, respectively) which stimulate our sex hormones production that control reproductive functions.
Only two hormones are being secreted by our posterior pituitary gland: oxytocin and antidiuretic hormone (ADH). The latter controls the conservation of water levels in your kidneys and blood pressure, while oxytocin stimulates milk secretion during breastfeeding and many other functions. Oxytocin also plays an especially important role in social interactions and bonding.
How Age Affects Hormone Levels
As we age, our hormone levels either increase or decrease, with the exception of a few hormones that remain relatively unaffected by age. Obviously, puberty in our teenage years is among the most hormonal time period in our lives; our hormone levels spike dramatically during this time and cause a myriad of physical and psychological changes.
By the time we reach our late 30s to early 40s, our hormonal levels have started to change ever so slightly and continue to do so as we age.
Like other bodily functions, endocrine function tends to slow down as we get older, meaning that even if our hormone levels don’t change, our receptors to them have become less sensitive.
As we age, our levels of FSH and LH may increase, as well as parathyroid hormone. Increased levels of parathyroid hormone can be a contributing factor to osteoporosis.
Meanwhile, our estrogen and testosterone levels decline with age, along with melatonin and growth hormone.
Most of us can recall at least one time in our lives where we felt as though we had little control over our actions, usually in the midst of a highly emotional situation. Puberty especially can wreak havoc on our emotions and cause us to act out in ways that can be described as erratic or moody.
So, does this mean our hormones affect our behavior? Sort of, but it works both ways. The things we do can also inhibit or cause an overproduction of certain hormones. The study of this phenomenon is called behavioral endocrinology.
Dr. James Giordano, Professor of Neurology and Biochemistry at Georgetown University Medical Center in Washington, DC, explains: “The brain is an endocrine target organ, which means that many hormones can – and do – affect its structure during development, and activities of thought, emotion, and behavior throughout the lifespan. For example, the brain is formed and develops with subtle differences in males and females because of the organizing effects of both maternal estrogen and the stress hormone cortisol, as well as the fetus’s production of adrenal sex hormones. During puberty, the adrenal sex hormones trigger the brain to release gonad hormone stimulating chemicals, which then activate the gonads – the ovaries in females and testes in males – to begin to produce their respective hormones, estrogen and progesterone, and testosterone.”
Dr. Giordano goes on to explain, “Throughout life, the interaction of the gonadal hormones and cortisol can affect the various neurotransmitter systems of the brain, modify neurological network activity, and in these ways, influence cognition, feelings and dispositions to, and expressions of various behaviors.”
Dr. Giordano says, “The neuro-hormone oxytocin is produced by nerve cells in the hypothalamus and specific other nerve cells elsewhere in the brain,” says Dr. Giordano. “Projections of these nerve cells interact with neurological nodes and networks that utilize the neurotransmitters serotonin and dopamine, and which are involved in the regulation of feelings of affiliation, reinforcement, and reward. It appears that an increase in brain oxytocin can affect the release of serotonin and dopamine, and in this way, heighten interpersonal bonding, and feelings of attraction, satisfaction, and pleasure.”
However, Dr. Giordano goes on to explain that environmental factors also come into play. “It’s important not to be overly reductionistic. While oxytocin can evoke notable effects, the chemistry, hormonal regulation, and network activities of the brain are complex, and feelings and behaviors reflect the dynamic interaction of myriad network connections and biochemical effects. These can vary based upon developmental history, experience, learning and memory, and environmental circumstances. So while it is certainly accurate to say that our hormones and chemistry affect our thoughts, emotions, and actions, the whole of who and what we are seems to be greater than the simple sum of its parts.”
Needless to say, the functions of hormones are crucial, and it would benefit your health to keep an eye on any possible symptoms of hormonal imbalances that could cause health problems.