By Dr. Mercola
The Fantastical World of Hormones is a compelling new film exploring the history and discovery of hormones, including enormous advances in this area of medical science that have occurred over the past 10 years.
Recent discoveries about how the endocrine system works have transformed our understanding of the critical roles hormones play in health and disease.
Hormones are essential to just about every life process, from your growth and development to your metabolism and passions. Every multi-celled organism, plant or animal, uses hormones—from earthworms to killer whales.
The word "hormone" derives from the Greek word "hormon," which means "to excite" or "set in motion." They have shaped your life ever since you were an embryo—but as important as they are, hormones have remained somewhat of a medical mystery.
Hormones are not obvious compared to the beating of your heart or the peristalsis of your digestive tract, and other such biological processes that are more easily observed and quantified.
Understanding hormones requires that scientists also be medical detectives, and these "hormone detectives" have been responsible for the abundant twists and turns we've seen in the field of endocrinology, as recounted in the film.
This article will serve as a primer for understanding what hormones are, where they come from, and what they do in your body. Then we'll discuss what you can do to optimize your hormone function.
Packing Lots of Punch Into Small Packages
There are more than 80 identified human hormones, all with distinctly different roles. Each hormone is aimed at a specific target cell and has no effect on any other cells as it washes past them.
When a hormone acts on its specific target cell, it can change the way it behaves to make it perform a specific task. For example, the hormone adrenalin causes your heart to beat faster, and the hormone gastrin makes your stomach secrete gastric acid when eating certain foods.
Hormones exert their influence in very small concentrations—every molecule packs quite a punch! This is why endocrine-disrupting chemicals like BPA and phthalates are so dangerous even in tiny amounts.
They exert many different actions on many different time scales. For example, adrenalin acts on your heart for a few minutes, but estrogen secreted daily can have effects that last for years.
Some hormones are designed to stimulate the release of other hormones. Some exert effects throughout your body, whereas others act only on small, localized areas of tissue. Some hormones have very dramatic effects, whereas the effects of others are more subtle.
Hormone Types—Just the Basics
Hormones can be classified into four categories, based on how they work: Steroids, peptides, amino acid derivatives (amines), and eicosanoids.1 Steroid hormones include your sex hormones and adrenal hormones.
Peptides represent a wide variety of chemical messengers, including human growth hormone (HGH), insulin, and melatonin. Adrenalin is an amine, and prostaglandins (involved in inflammation) are eicosanoids. Hormones are kept in balance (homeostasis) through a complex feedback system, and their release is triggered by three principal mechanisms:2
- Specific molecules in your blood (e.g., certain minerals or nutrients that serve as feedback mechanisms)
- Stimulation by other hormones (this typically leads to a rhythmic release of hormones, rising and falling in a predictable pattern)
- Stimulation by signals from your nervous system (this typically leads to a short burst of a hormone, such as adrenalin)
Hormones can be endocrine and exocrine, depending on how they're released:
- Endocrine: Hormones released directly into your bloodstream from a ductless gland (pituitary, adrenal, thyroid, ovary, testicle, pancreas, etc.)3
- Exocrine: Hormones released into a duct or lumen, such as from your salivary glands or the gastric glands in your stomach4
Some organs have both endocrine and exocrine functions, such as your kidneys, pancreas, and gonads. When you see the phrase "endocrine system," this generally refers to your system of eight hormone-secreting glands, but not to the other hormone-secreting tissues and organs, such as the placenta, which secretes estrogens and progesterone during pregnancy.5
More and more of your tissues are being discovered to secrete hormones—in fact, it's likely that most of your body tissues produce hormones. For example, we now know that your stomach produces the "hunger hormone" ghrelin to help regulate appetite. Even your fat cells secrete hormones—including leptin, which plays an important role in fat storage.
The Discovery of 'Fat Hormones' Turned Endocrinology on Its Head
The field of endocrinology was really turned on its head in 1994 when molecular geneticist Jeffrey Friedman of Rockefeller University discovered that the "satiety hormone" leptin is produced by fat cells. Prior to this, your body fat was never considered to be an endocrine organ, and obesity was not generally considered an endocrine problem. All of that changed with the discovery that your fat cells are more or less "controlling" your brain—insofar as telling you when to stop eating, via the hormone leptin. According to Rockefeller University:6
"Leptin is secreted by fat cells into the bloodstream and acts on the brain to regulate food intake and energy expenditure. When fat mass falls, plasma leptin levels fall, stimulating appetite and suppressing energy expenditure until fat mass is restored. When fat mass increases, leptin levels increase, suppressing appetite until weight is lost. This system maintains homeostatic control of adipose tissue mass."
The problem is that this feedback loop between your fat cells and brain can malfunction, causing leptin receptors to lose their sensitivity. The more fat cells you have, the higher your leptin levels may be and the more "leptin resistant" you may become—this is akin to developing insulin resistance from chronically elevated insulin levels. Both insulin and leptin resistance are associated with obesity and type 2 diabetes and are a foundational problem underlying almost all chronic degenerative disease.
Drug treatments are unlikely to solve leptin resistance, just as they are ineffective and even counterproductive for insulin resistance. The ideal way to correct leptin resistance is through diet. A whole food diet that emphasizes good fats and avoids blood sugar spikes will improve both insulin and leptin sensitivity. A major category of hormones—your steroid hormones—are derived from cholesterol, showing you just how critical healthy fats are to your endocrine function, and therefore to your overall health and well-being.
When Hormones Run Amuck
A number of factors can affect your hormone function, such as aging, lifestyle, and environmental factors. These changes can alter your hormone production, hormone metabolism, and how well your target cells respond to hormone messengers. Age-related changes have been observed in nearly every gland. Other factors known to adversely affect endocrine function include the following:
- Genetics: congenital birth defects and mutations (missing or damaged chromosomes)
- Diseases, infections, autoimmune disorders, allergic reactions, and other health conditions
- Stress of all kinds, including emotional trauma and severe illness or injury
- Surgery, radiation, chemotherapy, drugs, and other medical procedures
- Endocrine disrupting chemicals (EDCs)
Hormone disruptions can affect you in a multitude of ways, such as decreased fertility, impaired immune response, and neurological changes that reduce your capacity for handling stress. Diet and lifestyle choices are important to keep hormones in check, but avoiding endocrine disrupting chemicals is also extremely important, for the following reason:7
"Some EDCs mimic natural hormone binding at the target cell receptor. (Binding occurs when a hormone attaches to a cell receptor, a part of the cell designed to respond to that particular hormone.) EDCs can start the same processes that the natural hormone would start. Other EDCs block normal hormone binding and thereby prevent the effects of the natural hormones. Still other EDCs can directly interfere with the production, storage, release, transport, or elimination of natural hormones in the body. This can greatly affect the function of certain body systems."
Endocrine disrupting chemicals (similar in structure to estrogen and found largely in plastic products), combined with toxic foods, lack of exercise, and low vitamin D levels, are contributing to precocious puberty and cancer. You can read about the 12 Worst Endocrine Disruptors here. Before moving on to tips for balancing your hormones naturally, let's take a look at the functions of some of your major hormones and what tissues produce them.
Handy Hormone Reference Guide
Obviously, a detailed discussion of every hormone is beyond the scope of this article. But here is a table that outlines many of the most recognizable hormones, with links to where you can go for more information.
Hormone Where It's Produced Primary Functions I. STEROID HORMONES: Derived from cholesterol, includes sex hormones and adrenal hormones (mineralocorticoids and glucocorticoids) Estrogens Ovaries, placenta, breasts, liver, adrenal glands, fat cells, hypothalamus,8 and others Female sexual development, breast development, menstruation, pregnancy, memory, and anti-aging Progesterone Ovaries, placenta, and CNS Female sexual development, breast development, menstruation, and pregnancy Testosterone Testes and ovaries Male sexual development, sex drive, sperm production, and muscle and bone mass DHEA (Dehydroepiandrosterone) Adrenals and brain9 Lean body mass, bone strength, immunity, heart health, and resistance to stress Pregnenolone Adrenals Memory and resistance to stress Cortisol Adrenals Resistance to stress, energy production, anti-inflammatory, and mood stability Vitamin D (1,25 dihydroxyvitamin D or calcitrol) Skin, liver, and kidneys Varied, including bone and muscle health, heart health, immunity, metabolism, brain development, cell communication, and more II. PEPTIDE HORMONES: Often in "pre-hormone" form, requiring further processing to be active HCG (human chorionic gonadotropin) Placenta Helps support the endometrial lining for a developing fetus (and stimulates progesterone) HGH (Human growth hormone, or somatotropin/somatropin) Pituitary Promotes growth in children and adolescents, and helps regulate body composition, tissue growth, and metabolism in adults Melatonin Pineal gland Sleep; supports brain health, heart health, immune system, and cancer prevention Insulin Pancreas Signals glucose to be transferred from your blood into your cells for energy usage; fat body regulation Glucagon Pancreas Signals liver to release glucose into your blood Prolactin Pituitary, breasts, uterus, prostate, skin, fat, and immune cells Promotes lactation, bonding, and more than 300 reproductive, metabolic, immune, and other functions10 Adrenocorticotropic hormone (ACTH) Pituitary Stimulates cortisol release Leptin Fat cells Fat regulation Ghrelin Stomach and pancreas Stimulates hunger Parathyroid hormone (PTH) Parathyroid gland Controls amount of calcium in your bones and blood Thyrotrophin-releasing hormone (TRH) Hypothalamus Stimulates the thyroid gland to release TH Humoral factors (e.g., thymosin) Thymus Development of a healthy immune system III. AMINO ACID DERIVATIVE HORMONES (AMINES): Derived from tyrosine and tryptophan, includes thyroid hormones and catecholamines Adrenalin Adrenals "Fight or flight" response: increases heart rate, dilates blood vessels, and releases glucose Thyroid hormone (TH) Thyroid gland Organ development and metabolism IV. Eicosanoid hormones: Produced from fatty acids (arachidonic acid); very short-lived in your body and exert effects primarily on local tissues Prostaglandins Nearly every cell in the human body Varied, including uterine contractions, bronchodilation, inflammation, etc.
Hormone Imbalance Causes Much More Than Hot Flashes
As you have seen, hormones have far-reaching effects in your body, and hormone deficiencies can wreak total havoc on your health. When you think about unbalanced hormones, "hot flashes" are but one of many possible effects. For example, research published in 201311 suggests that what is typically thought of as "age-related cognitive decline" may actually be caused by estrogen deficiency. The health of your brain's synapses is closely linked to cognitive decline, and estrogen actually restores synaptic health, thereby improving memory. Maintaining hormone balance as you age does not mean you must use hormone replacement—there are a number of effective lifestyle strategies you can implement first.
Addressing your food choices should be your first step. If tweaking your diet is not enough, then the next best option is bioidentical hormone therapy. You can read more about how to proceed with this in a safe and effective manner by watching my interviews with Dr. Jonathan Wright and Dr. Theirry Hertoghe. Dr. Hertoghe specializes in the link between diet and hormones. Natural bioidentical hormones can offer relief from menopausal symptoms and are much safer than the synthetic versions, but I still don't recommend them as your first line option due to potential side effects.
The Link Between Diet and Hormone Health
Avoiding processed foods is one of the best strategies for preserving your natural hormone function. Refined carbohydrates and damaged fats can elevate your estrogen levels—as much as twice of what is normal. This is a major cause of menopausal symptoms in the first place. Processed foods may also reduce other critical hormone levels and are loaded with health-degrading ingredients such as sugar (especially fructose), GE ingredients, trans fats, processed salt, and other chemical additives.
On the other hand, consuming a diet rich in whole organic foods, with high-quality proteins and fats, can go a long way toward keeping your hormones balanced as you age—especially when combined with an effective fitness program. As a general rule, fat-soluble vitamins have a beneficial effect on sex hormones. Consuming foods rich in vitamin A will benefit progesterone production. Here's a quick list of Dr. Hertoghe's dietary recommendations for maintaining healthy hormone levels:
Eat a Paleolithic diet, rich in fresh organic vegetables and fermented foods Avoid sugar and fructose, including fresh fruit juice, as the rapid sugar spike effectively blocks hormone secretion; choose low-fructose fruits Dark green leafy vegetables are rich in magnesium, which facilitates sex hormone production Avoid regular alcohol consumption, as this decreases your growth hormone production Avoid unsprouted grains. If consuming grains (which are best avoided altogether), make sure they're sprouted Eat high-quality protein such as fish, grass-fed red meat, and pastured chicken, but cook them at a lower temperature
Additional Considerations Before Taking Hormones for Menopause
If you continue to have unpleasant menopausal symptoms after implementing the dietary changes outlined above, you might try a few of these other strategies before resorting to bioidentical hormone treatment:
- Phytoestrogens: Consuming plenty of phytoestrogens (plant-estrogens) such as licorice and alfalfa prior to menopause can help moderate your day-to-day estrogen levels so that when menopause arrives, the drop won't be so dramatic. However, avoid using unfermented soy, as it can wreak havoc on your health in a number of different ways.
- Optimize your vitamin D levels: This is a must for gene regulation and optimal health.
- Polyphenols: Certain polyphenols have been shown to have HRT-like benefits without the drawbacks, and are associated with a lowered risk of heart disease. Royal Maca is an excellent adaptogenic herbal solution for menopause that may women have found helpful. Avoid the inexpensive varieties as they typically don't work—instead, opt for the authentic version from Peru.
- Animal-based omega-3 fat: You'll also want to get plenty high-quality animal-based omega-3 fats, such as krill oil.
- Black cohosh: While dismissed by ACOG as having no scientific foundation, Black cohosh may indeed help regulate body temperature and hot flashes in some women.
As you can see, hormones are a complicated subject—but worth the effort due to the powerful roles they play in your health. I strongly recommend taking the time to watch this documentary, as it will broaden your understanding and help you take control of your health!