Erectile dysfunction (ED) and decreased libido can be an uncomfortable topic for many men. Culturally, we talk extensively about the role of estrogen and its effects on women’s bodies, but the conversation about testosterone as it relates to sexual function receives decidedly less attention. Erectile dysfunction often occurs with other more serious conditions, such as high blood pressure, diabetes, and elevated cholesterol levels, making it important to first rule out any underlying disorders. In other cases, testosterone is either too low or there is not enough hormone available to support healthy libido and erections. Depending on the cause, we can use a variety of herbs, amino acids, and nutrients to promote sexual health and function.
Citrulline & Arginine: Nitric Oxide and Vasodilators
Once we’ve ruled out more sinister causes of ED, we can use amino acids like arginine and citrulline to support erection quality. These amino acids increase a substance called nitric oxide (NO), which works in the body as a vasodilator. Vasodilation, or the widening of blood vessels, is important for healthy blood flow and therefore, stronger erections. Medications like Viagra work by inhibiting an enzyme called PDE-5, resulting in vasodilation. When a patient reports trouble attaining or maintaining erection, but does not note a decrease in libido or desire, it’s likely that the problem is related to perfusion (blood flow), rather than hormones. Instead, if a patient tells me he is experiencing decreased libido, it becomes important to determine whether an imbalance in hormones can be affecting sexual function.
Testosterone Testing: It’s Not Just About the Total
Maintaining healthy testosterone (T) levels is part of a complex process, which is why it’s essential to test more than just total testosterone levels. All too often, I see men with symptoms of erectile dysfunction and decreased libido and find that only the most basic blood tests have been ordered to assess hormone function. On symptomatic patients, I like to run what I call a “full” testosterone panel, one that includes free and bioavailable testosterone, in addition to a protein called sex hormone-binding globulin (SHBG). Depending on a man’s age, only 1-2% of testosterone in the body is “free and available” for use; the rest is attached to hormones while being transported throughout the bloodstream. By testing the free and bioavailable testosterone, we’re able to determine just how much testosterone is available for use to meet the body’s needs. It’s not uncommon to find healthy total testosterone levels, only to learn that bioavailable and free T are below range.
So how does testosterone become less available in the first place? For this, we have to look to the protein, sex hormone-binding globulin. Its function is to bind testosterone, but too much of this in men can mean that not enough testosterone is free and available to carry out its functions. The exact opposite is true for women, where low levels of SHBG can lead to too much free testosterone and unwanted symptoms, such as hair growth. This is why it’s important to test and consider SHBG when treating men with ED and low libido. If levels are too high, we can use herbs to lower SHBG in the blood, ultimately freeing up testosterone for use. By ordering more comprehensive blood work, we can treat the patient more specifically, targeting the problem at hand.
Estrogen & Aromatase: “A Vicious Cycle”
Some of my patients are surprised to learn that men, too, have estrogen in the body. While low levels are perfectly healthy, increases in estrogen can be problematic and cause unwanted symptoms like decreased libido, erectile dysfunction and gynecomastia (breast enlargement). A simple blood test will let us know whether estrogen levels are too high, but determining the source of this increase is key to treatment. One of the most common issues lies with an enzyme called aromatase, whose role is to convert testosterone into estrogen. Aromatase is abundant in adipose (fat) tissue, which means men who are overweight tend to have more aromatase than their healthy weight peers.
While it’s normal for testosterone levels to decline with each decade after 30, many men also tend to gain weight as they age, especially around the abdomen. This leads to a vicious cycle of sorts, where a patient gains weight with age, leading to excess aromatase, and ultimately, increased conversion of testosterone to estrogen. When coupled with an age-related decline in T levels, the effects become more evident. Fortunately, nature has several aromatase inhibitors, herbs or natural agents that work to block or inhibit the action of aromatase. When used over time, herbs like Urtica dioica and Passiflora incarnata can effectively limit the conversion of testosterone to estrogen, supporting healthy T levels while we work with the patient to manage weight.
Herbal Therapy and Supporting Nutrients
I use several herbs in my practice to support testosterone production, including Tribulus terrestris, Eurycoma longifolia, Panax ginseng, and Epidmedium, the infamous Horny Goat Weed. Since our goal is to support endogenous (internal) production of testosterone, patients should expect to supplement for several months before witnessing changes in hormone levels. As with any approach to treatment, it makes sense to ensure that the whole body is functioning optimally, and this includes checking the various nutrients that support testosterone levels. Zinc plays a fundamental role in healthy sperm production and zinc deficiency has been associated with low testosterone in numerous studies. We can also test DHEA levels in the body, which decline with age and can be helpful in supporting the production of testosterone. Since DHEA is a hormone and can also increase estrogen, I always recommend testing before supplementing with DHEA and caution against its use without the supervision of a doctor.
Antonio Reale, ND, MS is a licensed naturopathic physician and nutritionist practicing in Wethersfield and Middlebury, Connecticut. He specializes in personalized botanical medicine and is founder of The Herbal Room, a multidisciplinary wellness center in Wethersfield, with an in-house botanical dispensary. Dr. Reale also sees patients weekly at a satellite office in Middlebury. For insurance information and scheduling, visit: www.theherbal-room.com.