One of the greatest predictors of man’s health is his free testosterone levels.
Testosterone is a man’s life force. It influences every aspect of his body. It plays a crucial role in energy, muscle mass, cognition, mood, perception, reproduction, cardiovascular health, stress management, etc.
Maintaining healthy testosterone levels is essential for optimal health. For many years, the medical consensus was that testosterone directly fueled the growth of prostate cancer. This is because doctors assumed that because testosterone stimulates the growth of the prostate during puberty, it also stimulates growth of cancer later in a man’s life. This assumption led to the widespread practice of lowering testosterone levels as a treatment strategy. This approach, known as androgen deprivation therapy (ADT), reduces the availability of testosterone in an effort to slow cancer progression.
The notion that testosterone causes prostate cancer dates back to the 1940s, when Dr. Charles Huggins demonstrated that reducing testosterone levels through castration led to regression of advanced prostate cancer.
His findings created a misconception that higher levels of testosterone are inherently dangerous and promote the onset of prostate cancer. He concluded that lowering testosterone reduced the size of existing tumors, but it did not establish that testosterone levels cause cancer in the first place. This critical distinction was often overlooked, leading to the belief that high testosterone levels directly promote the onset of prostate cancer.
Unfortunately, Huggins may have not considered other factors that could be driving cancer growth, including the potential role of estrogen.
In his article on prostate cancer, Dr. Ray Peat notes that “By the age of 50, men often show an excess of both prolactin and estrogen, and a deficiency of thyroid and testosterone. This is the age at which enlargement of the prostate often becomes noticeable.”
Testosterone naturally decreases with age, so how could it be responsible for causing prostate cancer, which predominantly affects older men?
Today, researchers are continuously finding that it’s not simply the presence of testosterone but rather the hormonal balance between androgens and estrogens that influence cancer progression.
Estrogen and Prostate Cancer
In prostate cells, testosterone can be converted into estrogen. Elevated levels of estrogen can promote cellular proliferation and inflammation, creating an environment that fosters cancer growth. In fact, estrogen receptors are directly involved in the development of prostate cancer.
Huggins’s work suggests that reducing testosterone levels may have also reduced the process of aromatization—the conversion of testosterone into estrogen. This reduction in estrogen, rather than just the lowering of testosterone, could have contributed to the observed decrease in tumor size.
By inhibiting the aromatase enzyme with specific medications, the conversion of testosterone into estrogen is reduced, which can help prevent the onset and progression of prostate cancer.
A few things to consider about prostate cancer:
- Estrogen opposes testosterone. Historically, estrogens were used as a form of androgen deprivation therapy (ADT) to lower testosterone levels in men with prostate cancer. Unfortunately, estrogen itself is carcinogenic and can lead to worse outcomes when used to treat cancer.
- In animal studies, the administration of estrogen has been demonstrated to induce cancer in prostate tissues. A 2019 study found that administration of estrogen along with testosterone induced a 100% tumor incidence. However, administration of testosterone alone only induced 37% incidence (we can safely assume aromatization was occurring in some of these cases). (PMID: 30877616)
- Clinical studies have shown that testosterone replacement therapy (TRT) in men with low testosterone does not raise the risk of prostate cancer. In fact, numerous long-term studies have found no significant difference in prostate cancer rates between men receiving TRT and those who are not. These findings indicate that testosterone does not increase the risk of prostate cancer. (PMID: 38150256)
- Dihydrotestosterone (DHT), a potent androgen derived from testosterone, plays a protective role in prostate health. Unlike testosterone, which can be converted into estrogen, DHT cannot aromatize into estrogen. DHT is often found to be low in prostate cancer patients and some studies have shown that DHT can actually help treat prostate cancer.
These abdominal CT scans of a man with prostate cancer show that injections of testosterone reduced the size of metastatic tumors (red circles). Science Translational Medicine (2015).
- Testosterone plays a crucial role in a man’s immune function and ability to withstand stress. Depriving a man of testosterone while he is undergoing harsh cancer treatments like radiation and chemotherapy can cause significant negative effects. This increased vulnerability can lead to slower recovery, ultimately worsening cancer outcomes. Additionally, the loss of testosterone can negatively impact mood, energy levels, and cardiovascular health, further complicating the patient’s ability to withstand treatment.
So, if testosterone isn’t the primary driver of prostate cancer, what else could be at play? Research suggests several key factors:
- Elevated estrogen levels and exposure to xenoestrogens (PMID: 21765856)
- Exposure to toxins, including pesticides, heavy metals, mold, and pollution
- Chronic stress and high cortisol levels (PMID: 27509946)
- High prolactin (PMID: 31328184)
- Low thyroid function
- High intake of polyunsaturated fats (PMID: 31314803)
- Emotional conflicts, especially the trauma of losing a loved one
It’s important that we address all these potential factors rather than focusing solely on testosterone. A comprehensive approach offers better outcomes for patients.