Hormones are critical for human health. They play important roles in aging, mental health, reproduction, pregnancy, wellness and optimal health.
Both men and women share most of the hormones, but some are predominantly associated with one gender than the other.
Two well-known female hormones are progesterone and estrogen. Progesterone regulates monthly menstrual cycles, from menarche–first occurrence of menstruation–until menopause. Estrogen is responsible for reproduction and physical features among women.
There are three different types of estrogen–estradiol is the most commonly known. Other key hormones related to women’s reproductive health are luteinizing hormone (LH) and follicle stimulating hormone (FSH). Additionally, a pregnancy test checks for human chorionic gonadotropin (HcG) hormone, because it rises during the early stage of pregnancy.
Estrogen is also found in men at low levels. But tends to rise with age and weight gain, and is often associated with women-like features.
Among men, testosterone is the most commonly known male hormone.
While estrogen is considered the female hormone, testosterone projects an image of manliness and is the male hormone. One reason being its role in building strong muscles and bones.
Testosterone levels change continuously, peaking in early twenties and then slowly decline about one-percent per year. This age-related decline has made testosterone supplementation a hotly debated topic. A wide range of products are available as gels, patches, and sprays. At last count in 2013, over two million Americans were using them.
Many doping scandals include testosterone, since it helps heal the damage from the physical demands of sports.
Although women also produce testosterone, levels are about one-tenth that in men of similar age. High testosterone levels in women are often implicated in infertility and men-like features.
DHEA (dehydroepiandrosterone) is one of the main precursors to many of these hormones and plays an important role in reproductive health. As the plot above shows, levels strongly depend on age.
Beyond the hormones associated with gender and reproduction, several more contribute to everyday health.
Cortisol is the stress hormone, known for its role in fight or flight response.
Cortisol levels rise during signals of fear and anxiety, e.g., during public speaking or in exams or in anticipation of physical attack. In that sense, cortisol behaves like adrenaline, another important hormone known to give sudden boosts of energy.
Cortisol has a 24-hour cyclic rhythm that matches with our daily circadian rhythm. Levels shoot up in the morning, right after waking up, but then slowly decline to lowest levels around midnight. In a sense, the morning peak and drop follow the daily energy levels.
Cortisol release is tightly controlled by another hormone in the brain, called adrenocorticotropic (ACTH).
During the night, levels of yet another hormone, melatonin, rise during sleep. Melatonin release is controlled by pineal gland in the brain, and strictly follows the sleep cycle.
Insulin is one of the most well know hormones, critical for metabolism. It helps the lever digest food, in order to supply the energy our body needs to function. Insulin resistance, in diabetes, is one of the biggest challenges facing the world today.
The thyroid hormones are crucial for metabolism, development of babies before birth, and play a crucial role in maintaining body temperature. The T3 and T4 hormones are released by a butterfly shaped thyroid gland located in the throat, but their levels are carefully controlled by the thyroid stimulation hormone (TSH) from the hypothalamus.
Parathyroid hormones, which are also released by a tiny gland in the throat, play important role in bone development, through the absorption of calcium and phosphorus.
The human hormone production and release are controlled by a highly complex system of organs and glands in the body. These include, hypothalamus and pituitary glands in the brain, thyroid gland in throat, lever, kidneys, testes and ovaries. Most tissues in the body have hormone binding receptors which play important roles in balancing the levels for a well-functioning body.
Testing for hormones is easy as the field is well established. Often, a simple saliva sample might be sufficient to check the levels, making it easy to collect, ship, and test for various hormone levels. Saliva checks the active form of hormone–important, whenever a significant part of the hormone is bound and not actively performing the desired role.
A male health test checks for testosterone, cortisol, DHEA and estrogen in men. A female health test checks for progesterone as well. Depending on the gender, different ranges are carefully calibrated to ensure optimal levels are within healthy range for the specific gender.
A thyroid test checks for TSH, free T3, free T4, and TPO antibodies for a more comprehensive assessment of the thyroid gland. High TPO antibodies might be signs of autoimmune diseases.
An adrenal test check for DHEA and cortisol levels four-times during the day. In a sleep and stress test, melatonin, along with cortisol, is reported, for monitoring healthy sleep and levels of stress. Because several hormones are involved in digestion, weight management and wellness, a metabolism test checks for cortisol, low testosterone and TSH levels.
Despite the name, Vitamin D is also a hormone that is produced by the body on exposure to sun. Vitamin D test checks for optimal levels, which are essential for heart health, bone density, and mental health.
All About Cortisol - a review of the stress hormone.
All About Testosterone - a review of the male hormone.
Testosterone and Aging - how testosterone changes with age.
All About Vitamin D – review of symptoms and impact.
Saliva Testing - Advantages and Challenges – review of science on saliva based testing.
Cortisol: Risk Factors – review of key risk factors for the stress hormones.
Morning Cortisol Levels – Why levels and collection times are so important.