Hormone Therapy

HRT vs TRT – Is There a Difference?

An explanation of the relationship between hormone replacement therapy (HRT) and testosterone replacement therapy (TRT)

Testosterone replacement therapy (TRT) and hormone replacement therapy (HRT) are both medical treatments aimed at addressing hormonal imbalances in the body. While they share some similarities, they are primarily distinguished by the specific hormones they target and the conditions they are designed to treat.

Testosterone Replacement Therapy (TRT)

TRT is a type of HRT specifically focused on treating low testosterone levels, which can occur due to aging, certain medical conditions, or injury. Testosterone is a critical hormone for the development and maintenance of male secondary sexual characteristics and overall health. Low testosterone levels can lead to various symptoms, such as fatigue, mood changes, decreased sex drive, and reduced muscle mass. TRT aims to restore normal testosterone levels through the administration of testosterone via injections, gels, patches, or pellets.

Hormone Replacement Therapy (HRT)

HRT is a broader term that encompasses a variety of treatments designed to balance hormone levels in both men and women. HRT can involve the administration of various hormones, depending on the individual's needs and the specific hormonal imbalance being addressed. Some examples include:

  1. Estrogen and Progesterone: These hormones are commonly prescribed to women experiencing symptoms of menopause or for those who have had a hysterectomy. HRT can help alleviate hot flashes, mood swings, and other menopause-related symptoms.
  2. Human Chorionic Gonadotropin (HCG) and Human Menopausal Gonadotropin (HMG): These hormones are often used in fertility treatments, as they stimulate the development and release of eggs in women and sperm production in men.
  3. Thyroid Hormone: Thyroid hormone replacement is prescribed for individuals with hypothyroidism (an underactive thyroid gland), which can cause symptoms such as weight gain, fatigue, and depression. This therapy helps to regulate metabolism and overall energy levels.

While TRT is a specific form of HRT that targets testosterone levels, HRT is a more general term that includes a range of hormonal treatments for various conditions. Both therapies aim to restore hormonal balance and improve the quality of life for individuals experiencing symptoms related to hormonal imbalances.

Online Doctor prescribing TRT

Online TRT Clinics

A list of reputable testosterone replacement therapy options that offer online consultations and prescriptions.

First off - I have no affiliation with any of these companies. They have been vetted with research on multiple TRT forums and review sites. In some cases, I have spoken with someone at the company directly by phone or email. Pricing varies between each company and depends on which medications you are prescribed.

TRT Nation is a testosterone replacement therapy (TRT) clinic that specializes in helping men with low testosterone levels. They offer a range of testosterone replacement options, including injections, gels, and pellets, and work with patients to find the best solution for their individual needs. They also offer additional wellness services, such as weight loss programs and supplements. They can prescribe testosterone, human growth hormone (HGH) peptides, human chorionic gonadotropin (HCG), and even the trendy weight loss drug, semaglutide.

Frontline Alternative Medicine is a functional and integrative medicine clinic that offers testosterone replacement therapy as part of their comprehensive approach to men's health. They offer a range of testosterone replacement options, including injections, gels, and pellets, and also offer other hormone therapies, such as human chorionic gonadotropin (HCG) and dehydroepiandrosterone (DHEA).

Defy Medical is a telemedicine clinic that specializes in testosterone replacement therapy and offers a range of options, including injections, gels, and pellets. They also offer other anabolic therapies, such as HCG, oxandrolone, stanozolol and nandrolone.

Viking Alternative Medicine is a clinic that specializes in testosterone replacement therapy and offers a range of options, including injections and gels. They also offer other hormone therapies, such as HCG and stanozolol.

Do you have others to add to the list? Leave a comment and I'll check them out. Note: Please do NOT try to spam. I won't publish the comment. Instead, I'll vet the company and add it to the list if they are found to be a safe and legitimate TRT clinic.

A doctor with a male patient

Low Estrogen and Testosterone Replacement (TRT)

Is estrogen bad for men? What happens if your estrogen levels are too low?

The Importance of Maintaining Healthy Estrogen Levels for Men on Testosterone Replacement Therapy

While testosterone replacement therapy (TRT) is commonly prescribed for men with low testosterone levels, it's important not to neglect the role of estrogen in the male body. Estrogen, typically associated with women, is also present in men and plays a crucial role in bone health, cognitive function, and cardiovascular health.

We all know the nasty side effects that can happen if your estrogen levels are too high. Gynecomastia and bloating, are two examples. Instead, this article will explore the importance of maintaining healthy estrogen levels for men using testosterone replacement, discuss the use of anti-estrogen medications, and highlight the side effects of low estrogen in men.

The Role of Estrogen in Men

In men, estrogen is primarily produced through a process called aromatization, where the enzyme aromatase converts testosterone into estrogen (source). Estrogen levels in men should be within the normal range of 20-40 pg/mL (source). Both excessively high and low estrogen levels can lead to health issues. Men using testosterone replacement therapy may experience an increase in estrogen levels, which can be managed with the use of anti-estrogen medications.

Anti-Estrogen Medications

Anti-estrogen medications, such as estrogen blockers and aromatase inhibitors, are used to control estrogen levels in men undergoing testosterone replacement therapy. These medications work by either blocking the action of estrogen or by inhibiting the production of estrogen. Examples of anti-estrogen medications include:

  • Estrogen blockers: Tamoxifen and Clomiphene
  • Aromatase inhibitors: Anastrozole, Letrozole, and Exemestane

It is essential to work closely with a healthcare professional when using anti-estrogen medications, as they can lead to excessively low estrogen levels if not carefully monitored.

Side Effects of Low Estrogen in Men

Low estrogen levels in men can lead to a variety of health issues. Some side effects of low estrogen include:

  • Bone health: Low estrogen levels can result in decreased bone density and an increased risk of osteoporosis (source).
  • Cognitive function: Estrogen plays a role in maintaining cognitive function, and low levels can lead to memory issues and cognitive decline (source).
  • Cardiovascular health: Estrogen is involved in maintaining cardiovascular health, and low levels can result in an increased risk of heart disease (source).
  • Sexual health: Low estrogen levels can lead to sexual dysfunction, including erectile dysfunction and decreased libido (source).
  • Mood changes: Estrogen is associated with mood regulation, and low levels can contribute to mood swings, irritability, and depression (source).

While testosterone replacement therapy can provide significant benefits for men with low testosterone, it is essential to carefully monitor and maintain healthy estrogen levels. Anti-estrogen medications can be used to manage estrogen levels, but they should be used under the guidance of a healthcare professional to avoid excessively low estrogen levels. By maintaining a healthy balance of hormones, men can experience the full benefits of testosterone replacement therapy while minimizing potential health risks.

Types of Protein Powder

The Pros and Cons of Different Types of Protein Powders

First, let's explore the different types of protein supplements on the market. You can scroll down to the table below to see the pros and cons of each.

Whey Protein

Whey protein is derived from milk and is a byproduct of cheese production. It is one of the most popular types of protein powder due to its high-quality protein content, fast absorption rate, and affordability. Whey protein contains all essential amino acids and is particularly rich in branched-chain amino acids (BCAAs) that promote muscle growth and recovery (1). There are two primary forms of whey protein: whey concentrate and whey isolate. Whey isolate has a higher protein content and less lactose, making it a better option for individuals with lactose intolerance.

Casein Protein

Like whey protein, casein protein is also derived from milk. However, casein is absorbed more slowly than whey, providing a steady release of amino acids over an extended period. This slow digestion rate makes casein an ideal choice for a pre-bedtime protein supplement to support muscle recovery and growth throughout the night (2). Casein protein is also rich in calcium, which can contribute to bone health.

Pea Protein

Pea protein is a plant-based protein powder made from yellow split peas. It is a popular choice among vegans, vegetarians, and those with dairy or soy allergies. Pea protein is hypoallergenic, easily digestible, and rich in essential amino acids, particularly arginine and BCAAs (3). While its protein quality is slightly lower than whey, it still provides a valuable source of plant-based protein for muscle building and recovery.

Soy Protein

Soy protein is another popular plant-based protein powder made from defatted soybeans. It is a complete protein source containing all essential amino acids, and it is also rich in isoflavones, which may provide additional health benefits, such as reduced cholesterol levels (4). Soy protein is an excellent option for vegans, vegetarians, and individuals with lactose intolerance.

Brown Rice Protein

Brown rice protein is a plant-based protein powder derived from whole-grain brown rice. It is hypoallergenic and easily digestible, making it suitable for individuals with food sensitivities or allergies. While brown rice protein is not a complete protein source, as it lacks some essential amino acids, it can be combined with other plants.

Type Pros Cons
Whey Protein
  • High-quality protein content
  • Fast absorption rate
  • Rich in BCAAs
  • Affordable
  • Contains lactose (concentrate)
  • Not suitable for vegans and some vegetarians
Casein Protein
  • Slow digestion rate
  • Steady release of amino acids
  • Rich in calcium
  • Contains lactose
  • Not suitable for vegans and some vegetarians
Pea Protein
  • Plant-based
  • Hypoallergenic
  • Easily digestible
  • Rich in arginine and BCAAs
  • Protein quality slightly lower than whey
  • Some people may not enjoy the taste
Soy Protein
  • Plant-based
  • Complete protein source
  • Rich in isoflavones
  • May not be suitable for individuals with soy allergies
  • Some concerns about estrogen-like effects
Brown Rice Protein
  • Plant-based
  • Hypoallergenic
  • Easily digestible
  • Not a complete protein source
  • May need to be combined with other protein sources
Hemp Protein
  • Plant-based
  • Rich in omega-3 and omega-6 fatty acids
  • High in fiber
  • Easily digestible
  • Protein content lower than other sources
  • Can be more expensive

Pin Cushion

How Many Injections Will You Take for TRT Over Your Lifetime

When I started testosterone replacement therapy in my early thirties, I didn't give much thought to how many injections I would be taking over the course of my life. Now at the age of 46, I've been sticking myself with needles every week for over a decade -- and let me tell you, these shots add up!

You're going to be a pin cushion. This is especially true if you take multiple injections per week like I do (Testosterone Enanthate twice weekly). One thing that helps is what I call "The Macarena Approach". For those of you too young to remember the pre-TikTok TikTok dance, watch this. It goes something like this: Left glute, right glute, left delt, right delt, left thigh, right thigh, repeat...

Use the calculator below to figure out how many injections you'll be taking over the course of your life once you start TRT. The results might surprise you. Just imagine all of the scar tissue that will build up.

Testosterone Injection Calculator

Based on the average lifespan of men in the United States: 76

Related: Try out the TRT Dose Calculator to find out the correct dosage per injection.

Testosterone converting to DHT

How Testosterone Converts to DHT and Estrogen

Exploring the complex pathways of testosterone conversion to DHT and estrogen metabolism in men.

Testosterone plays a significant role in the development of male reproductive tissues, as well as secondary sexual characteristics. However, its functions extend beyond its direct actions, as it also serves as a precursor for dihydrotestosterone (DHT) and various types of estrogen. This article explores the biochemical pathways by which testosterone is converted into these biologically active metabolites, and the physiological implications of these conversions.

Testosterone Conversion to DHT

DHT is a potent androgen, with approximately 2.5-10 times higher affinity for the androgen receptor than testosterone (Jenkins et al., 1992). The conversion of testosterone to DHT occurs primarily in peripheral tissues, such as the skin, prostate, and hair follicles, and is catalyzed by the enzyme 5?-reductase (Imperato-McGinley et al., 1992). Three isoforms of 5?-reductase have been identified, with types 1 and 2 being the most relevant for DHT synthesis (Thigpen et al., 1993).

DHT is a key hormone involved in the development of male external genitalia and the onset of puberty. It also plays a critical role in prostate growth and male pattern baldness. Excessive DHT levels have been implicated in the development of benign prostatic hyperplasia (BPH) and prostate cancer (Gormley et al., 1992).

Testosterone Conversion to Estrogens

Contrary to popular belief, estrogens are not exclusively female hormones. They are also synthesized in males, albeit in smaller amounts, just as women produce testosterone in smaller amounts than men.

Testosterone can be converted to estradiol (E2), the most potent estrogen, by the enzyme aromatase (CYP19A1) (Simpson, 2003). This reaction occurs primarily in adipose tissue, liver, brain, and testes.

Estrogens play a crucial role in bone metabolism, preventing bone loss in both men and women (Oz et al., 2000). They are also involved in the regulation of male reproductive function and the maintenance of cognitive health. However, elevated estrogen levels in men have been associated with an increased risk of gynecomastia, cardiovascular disease, and certain types of cancer (Bagatelle & Bremner, 1995).

Testosterone's actions extend beyond its direct effects, serving as a precursor for both DHT and various types of estrogen. The conversion of testosterone to these biologically active metabolites is mediated by specific enzymes and occurs in various tissues throughout the body. Understanding the complex interplay between testosterone, DHT, and estrogen metabolism is essential for comprehending the hormonal balance in men and its impact on health and disease.

The conversion of testosterone to DHT, catalyzed by the 5?-reductase enzyme, has significant implications for male sexual development, hair growth patterns, and prostate health. On the other hand, the aromatase-mediated conversion of testosterone to estrogen, particularly estradiol, plays a crucial role in bone metabolism, male reproductive function, and cognitive health.

To make a long story short:

While you may want to take aromatase inhibitors while on TRT, you also wouldn't want to completely suppress your body's ability to create estrogen, such as estradiol, because even men need some estrogen to function properly.


Bagatell, C. J., & Bremner, W. J. (1995). Androgens in men—uses and abuses. The New England Journal of Medicine, 332(11), 707-714.

Bélanger, A., Candas, B., Dupont, A., Cusan, L., Diamond, P., Gomez, J. L., & Labrie, F. (2006). Changes in serum concentrations of conjugated and unconjugated steroids in 40- to 80-year-old men. Journal of Clinical Endocrinology & Metabolism, 81(10), 3620-3625.

Bhasin, S., Storer, T. W., Berman, N., Callegari, C., Clevenger, B., Phillips, J., ... & Casaburi, R. (2001). The effects of supraphysiologic doses of testosterone on muscle size and strength in normal men. New England Journal of Medicine, 335(1), 1-7.

Bulun, S. E., Chen, D., Moy, I., Brooks, D. C., & Zhao, H. (2005). Aromatase, breast cancer and obesity: a complex interaction. Trends in Endocrinology & Metabolism, 22(2), 55-61.

Gormley, G. J., Stoner, E., Bruskewitz, R. C., Imperato-McGinley, J., Walsh, P. C., McConnell, J. D., ... & Lieber, M. M. (1992). The effect of finasteride in men with benign prostatic hyperplasia. New England Journal of Medicine, 327(17), 1185-1191.

Grino, P. B., Griffin, J. E., & Wilson, J. D. (1990). Testosterone at high concentrations interacts with the human androgen receptor similarly to dihydrotestosterone. Endocrinology, 126(2), 1165-1172.

Imperato-McGinley, J., Guerrero, L., Gautier, T., & Peterson, R. E. (1992). Steroid 5?-reductase deficiency in man: an inherited form of male pseudohermaphroditism. Science, 186(4170), 1213-1215.

Jenkins, E. P., Andersson, S., Imperato-McGinley, J., Wilson, J. D., & Russell, D. W. (1992). Genetic and pharmacological evidence for more than one human steroid 5?-reductase. Journal of Clinical Investigation, 89(1), 293-300.

Kaufman, K. D., & Dawber, R. P. (1999). Finasteride, a type 2 5?-reductase inhibitor, in the treatment of men with androgenetic alopecia. Expert Opinion on Investigational Drugs, 8(4), 403-415.

Oz, O. K., Millsaps, R., Welch, R., Birch, J., & Zerwekh, J. E. (2000). Expression of aromatase in the human osteoblastic cell line, Saos-2. Bone, 26(5), 521-526.

Simpson, E. R. (2003). Sources of estrogen and their importance. Journal of Steroid Biochemistry and Molecular Biology, 86(3-5), 225-230.

Swerdloff, R. S., & Wang, C. (2004). Androgens and the ageing male. Best Practice & Research Clinical Endocrinology & Metabolism, 18(3), 349-362.

Thigpen, A. E., Silver, R. I., Guileyardo, J. M., Casey, M. L., McConnell, J. D., & Russell, D. W. (1993). Tissue distribution and ontogeny of steroid 5?-reductase isozyme expression. Journal of Clinical Investigation, 92(2), 903-910.

Testosterone Replacement Therapy Laws in the US

A brief summary of the laws governing TRT in the United States

  1. Controlled Substances Act (CSA): The CSA is a federal law that regulates the manufacture, distribution, and dispensing of controlled substances, including testosterone. Testosterone is classified as a Schedule III controlled substance under the CSA, which means that it has a moderate to low potential for abuse and dependence.
  2. Food, Drug, and Cosmetic Act (FDCA): The FDCA is a federal law that regulates the safety and effectiveness of drugs and medical devices. Testosterone replacement therapy products are subject to regulation by the FDA under the FDCA.
  3. Drug Enforcement Administration (DEA) Regulations: The DEA is responsible for enforcing the CSA and has established regulations governing the registration, prescribing, and dispensing of controlled substances, including testosterone.
  4. State Medical Boards: State medical boards regulate the practice of medicine within their respective states, including the prescribing and administration of testosterone replacement therapy. State medical boards can discipline or revoke the licenses of healthcare providers who violate state laws or regulations related to testosterone replacement therapy.

Testosterone Molecule

An Abbreviated History of TRT

A timeline of testosterone replacement therapy milestones

  • 1849: Arnold Adolph Berthold, a German physiologist, conducts experiments on roosters and observes that removing their testes causes changes in their physical characteristics.
  • 1889: Charles-Édouard Brown-Séquard, a French physician, injects himself with a concoction made from the testicles of dogs and guinea pigs, claiming that it improved his physical and mental health.
  • 1935: The chemical structure of testosterone is first identified by Ernst Laqueur, a Dutch biochemist.
  • 1937: The first clinical trial of testosterone replacement therapy is conducted by Paul Heinrich Emmett and Enrest Laqueur in Amsterdam. They administer testosterone to a patient with low testosterone levels and report improvements in his physical and mental health.
  • 1944: The first synthetic form of testosterone, testosterone propionate, is developed.
  • 1953: A study published in the Journal of the American Medical Association (JAMA) reports that testosterone replacement therapy can improve muscle mass and strength in men with low testosterone levels.
  • 1960s: Testosterone replacement therapy becomes more widely available and is prescribed to men with low testosterone levels.
  • 1970s-1980s: The use of testosterone replacement therapy declines due to concerns about the risk of prostate cancer and cardiovascular disease.
  • 1990s: The development of newer forms of testosterone, such as testosterone enanthate and testosterone cypionate, leads to a renewed interest in testosterone replacement therapy.
  • 2000s: Testosterone replacement therapy becomes more popular, with sales of testosterone increasing rapidly.
  • 2010s: Studies suggest that testosterone replacement therapy may increase the risk of cardiovascular disease and prostate cancer in some men, leading to increased scrutiny of the safety and efficacy of testosterone replacement therapy.
  • 2015: The FDA issues a safety alert warning that testosterone replacement therapy may increase the risk of heart attack, stroke, and death in some men, leading to increased regulation of testosterone replacement therapy.

Today, testosterone replacement therapy continues to be a popular treatment option for men with low testosterone levels. However, it is important for individuals to work with a qualified healthcare provider to determine the appropriate form and dosage of testosterone for their individual needs and to monitor for potential side effects.

Side Effects

10 TRT Side Effects to Talk to Your Doctor About

While TRT can be an effective treatment for men with low testosterone, there are several potential side effects and risks that your doctor may not have fully explained to you. Here are ten things you should know about testosterone replacement therapy:

  1. High hematocrit levels: Testosterone can stimulate the production of red blood cells, which can lead to an increase in hematocrit levels. High hematocrit levels can increase the risk of blood clots, stroke, and heart attack. Regular monitoring of hematocrit levels is necessary during TRT. I am a regular at the local blood donation centers because it helps me keep my hematocrit levels low. Win-Win!
  2. Hair loss: TRT can lead to an increased risk of hair loss in men who are genetically predisposed to male pattern baldness. If you are concerned about hair loss, talk to your doctor about alternative treatments or medications that can help. Speaking of...
  3. Side effects of medications for hair loss: Medications commonly used to treat hair loss, such as finasteride, can have sexual side effects such as decreased libido, gynecomastia and erectile dysfunction.
  4. Gynecomastia: TRT can lead to an imbalance of hormones that can cause the development of breast tissue in men. This condition, known as gynecomastia, can be treated with medications or surgery if it becomes a concern.
  5. Side effects of medications for gynecomastia: Medications commonly used to treat gynecomastia, such as tamoxifen, can have side effects such as hot flashes and mood changes.
  6. Testicular shrinkage: TRT can lead to testicular shrinkage due to a decrease in natural testosterone production. This is typically a temporary side effect and may be reversed by discontinuing TRT.
  7. Infertility: TRT can suppress the production of sperm in the testicles, which can lead to infertility. If you are interested in preserving fertility, talk to your doctor about options such as sperm banking before starting TRT.
  8. Increased risk of prostate cancer: TRT has been associated with an increased risk of prostate cancer, particularly in men over the age of 65. Regular prostate exams and monitoring are necessary during TRT.
  9. Skin irritation: TRT can lead to skin irritation at the application site of topical testosterone gels or patches.
  10. Cardiovascular risks: TRT has been associated with an increased risk of cardiovascular events such as heart attack and stroke, particularly in men with pre-existing cardiovascular disease. Your doctor should carefully evaluate your cardiovascular risk factors before prescribing TRT.

Middle Aged Man with Low Testosterone

What Causes Low-T? Why Do I Have Low Testosterone?

In this article, we will explore the potential causes of low testosterone, ranging from genetic factors to environmental influences and lifestyle choices.


Testosterone levels naturally decline as men age. Studies have shown that testosterone levels decrease by approximately 1% per year after the age of 30. This gradual decline is a normal part of the aging process and may be responsible for some of the symptoms associated with "male menopause" or andropause.

Genetic Factors

Some men may have a genetic predisposition to low testosterone levels. For example, Klinefelter Syndrome, a genetic disorder affecting approximately 1 in 500-1,000 men, is characterized by the presence of an extra X chromosome and can result in low testosterone production.

Environmental Factors

Exposure to certain environmental toxins, such as pesticides and heavy metals, can disrupt hormone production and contribute to low testosterone levels. A study published in the journal Human Reproduction Update found that exposure to endocrine-disrupting chemicals (EDCs) could adversely affect male reproductive health, including reduced testosterone levels.

Drug Abuse

The abuse of certain drugs, such as opioids and anabolic steroids, can negatively impact testosterone production. Long-term opioid use has been shown to suppress the hypothalamic-pituitary-gonadal axis, leading to decreased testosterone levels. Similarly, anabolic steroid abuse can suppress the body's natural testosterone production, resulting in low testosterone levels once steroid use is discontinued.


Elevated estrogen levels can suppress testosterone production in men. Aromatase, an enzyme responsible for converting testosterone into estrogen, can be overactive in some individuals, leading to an imbalance in hormone levels. Certain medications, such as aromatase inhibitors, can help address this issue by reducing estrogen production and supporting healthy testosterone levels.


A poor diet, particularly one high in processed foods and low in essential nutrients, can negatively impact testosterone levels. Research has shown that diets rich in healthy fats, such as monounsaturated and polyunsaturated fats found in olive oil, nuts, and fish, can support optimal testosterone production. Additionally, ensuring adequate intake of key nutrients, such as zinc and vitamin D, is essential for maintaining healthy testosterone levels.


Carrying excess body weight, particularly in the form of visceral fat, can negatively affect testosterone levels. A study published in the journal Clinical Endocrinology found that obese men had significantly lower testosterone levels compared to their non-obese counterparts. Losing weight through a combination of healthy diet and regular exercise can help improve hormone balance and support optimal testosterone production.

Low testosterone levels can result from a variety of factors, including age, genetics, environmental exposure, drug abuse, estrogen levels, diet, and weight. Understanding these potential causes can help individuals make informed decisions about how to address their low testosterone levels and improve overall hormonal health. If you suspect you have low testosterone, it is essential to consult a healthcare professional for a proper evaluation and guidance on the most appropriate course of action.