Hormones 101: What Hormones Are and How They Affect You

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Hormones are the chemical messengers that travel, via our bloodstream, to every organ and tissue in the body. They influence fat storage, energy levels, sex drive, brain health and a host of other vital functions.

Find out below about some of the most important functions of your hormones and how too much, too little or wrong ratios of these have a tremendous effect on your health.

Hormones 101


Testosterone is secreted primarily by the testicles of males and, to a lesser extent, the ovaries of females. In males, testosterone protects against cardiovascular disease, hypertension and arthritis. It leads to improved lean muscle mass, increased bone density, decreases in cholesterol, improved skin tone, improved healing capacity, and increased libido and sexual performance. It prolongs the quality of life by decreasing age-related diseases—as does estrogen in females. Testosterone is also extremely important in females for body fat reduction, sense of well-being, libido, endurance and energy.

Growth Hormone

This hormone, made by the pituitary gland, goes hand-in-hand with testosterone. Growth hormone contributes to ongoing tissue repair, cell rejuvenation, bone and muscle strength, brain function, enzyme production, integrity of hair, nails and skin and fat breakdown.

The signs of growth hormone deficiency are significantly correlated to the signs of aging: body composition shifts from lean muscle mass and high energy levels to increased fat/body weight and low energy levels, decreased bone mineralization (bone growth slows), vitality ebbs, cardiovascular disease and mortality increase.

Decreased human growth hormone also has psychosocial effects like impaired physical performance, poor sleep, and decreased social interaction. Growth hormone supplementation can result in significant improvements in energy, sense of well-being, along with decreased muscle pain, body fat and signs of aging such as wrinkles.


Women synthesize most of their estrogen in their ovaries and other reproductive tissues. Men need to produce estrogen through a process involving an enzyme called aromatase that transforms testosterone into estradiol. In men, estrogen is thought to affect sperm count.

In women, estrogen protects against heart disease, stroke, osteoporosis, Alzheimer’s Disease, memory disorders, vaginal atrophy and urinary incontinence. It also prevents symptoms of menopause, including hot flashes, irritability, mood swings and temperature dysregulation.

Estrogen deficiency results in sagging breast tissue and skin, increased facial wrinkles, fatigue, depression, mood swings and decreased libido. Estrogen is instrumental in orchestrating the menstrual cycle and works in harmony with progesterone, both of which are essential to normal, healthy female function.


Progesterone is a hormone released by the corpus luteum in the ovary. It is a pivotal building block for the production of other hormones, including estrogens, glucocorticoids and corticosteroids. Without progesterone there would be no menstrual cycle or reproduction. It also plays an essential role keeping the stimulatory effects of estrogen under control. Progesterone protects against uterine and breast cancers, osteoporosis, fibrocystic disease and ovarian cysts.


Cortisol is produced by the adrenal glands and is meant to control energy levels in times of stress. This helps us escape danger or recover from extreme effort. Periods of stress cause the body to break down proteins and release glucose into the blood stream. Short spikes of the hormone are necessary and not a cause of worry. But when cortisol levels are imbalanced (either too low or too high at all times), it can be a symptom of chronic, unresolved stress. This can lead to cardiovascular issues and a wide range of other health problems.


This is the most abundant hormone in the body and is mainly secreted by the adrenal glands but is also produced by the skin and brain. It is an essential component in many of the body’s physiological and metabolic functions including building the immune system, reversing the effects of stress, regulating hormone balance and helping maintain levels of well-being. It promotes an anabolic or protein building state, which increases breakdown of fat. It can increase energy, strength and libido. Studies link it to reduced cardiovascular risk and restored sexual vitality.

DHEA levels naturally start to decline after the age of 30, which is precisely when many adults start to experience weight gain, sluggishness, lowered libido and other symptoms caused by higher levels of inflammation. By the time someone reaches the age of about 75, they produce only about 10 to 20 percent of the original DHEA they created in their youth.


Pregnenolone is a precursor hormone synthesized from cholesterol, principally in the adrenal glands, but also in the liver, skin, brain, testicles, ovaries, and retina of the eyes.

It functions as a memory enhancer, and is a factor in cellular repair, particularly in the brain and nerve tissue. It protects against neuronal injury and facilitates cerebral function.


Melatonin is produced by the pineal gland (in the brain). It is a neurotransmitter hormone that regulates circadian rhythm (your patterns of sleep). Deep sleep helps energize the body, improve immune function, growth hormone production and mood. Melatonin has powerful antioxidant effects, which also helps disease prevention. Melatonin deficiency is linked to poor sleep, jet lag, irritability, hypersensitivity and premature aging. Studies also link it to inhibiting breast cancer cell proliferation.

Thyroid hormone

Produced by the thyroid gland, this metabolic hormone regulates temperature, metabolism and cerebral function. It contributes to energy levels and the body’s ability to maintain a constant temperature. It increases fat breakdown, improves head hair growth, reduces cholesterol levels and bodyweight.

As you can see, hormones can have a powerful effect on your body. Understanding how and why they affect your health can be a key factor in getting and maintaining the physique you want. Healthy behaviors like regular exercise, proper nutrition, and adequate sleep can go a long way in keeping hormone levels in check.