November 6, 2023 • 2hr 34min
Dr. Michael Eisenberg: Improving Male Sexual Health, Function & Fertility
Huberman Lab
Key Takeaways
- Sperm quality appears to be declining globally over time, though the exact reasons are debated. Potential factors include environmental exposures, obesity, and lifestyle changes.
- Testosterone levels also seem to be declining on average, likely due to factors like obesity and environmental exposures. However, there is wide individual variation.
- Only about 5-10% of erectile dysfunction cases are due to low testosterone. The majority are related to vascular/blood flow issues.
- Medications like Viagra/Cialis work for 60-70% of erectile dysfunction cases by improving blood flow. Other options include injections and implants.
- Finasteride and similar drugs for hair loss can sometimes cause sexual side effects, including potentially long-lasting issues in some men (post-finasteride syndrome).
- Semen quality is an important marker of overall health in men. Low quality is associated with higher risks of various health issues.
- P***s length appears to be increasing slightly over time, for reasons that are not yet clear.
- Pelvic floor health is important for sexual and urinary function in men. Both overly tight and overly weak pelvic floors can cause issues.
- Regular testicular self-exams are no longer officially recommended, but men should still be aware of any changes or lumps.
- Getting baseline hormone levels and semen analysis done, even for young healthy men, can provide valuable health information.
Introduction
In this episode, Dr. Andrew Huberman interviews Dr. Michael Eisenberg, a urologist and professor specializing in male sexual function and fertility at Stanford University. They discuss a wide range of topics related to male reproductive and sexual health, including testosterone levels, sperm quality, erectile function, prostate health, and more. Dr. Eisenberg shares insights from his clinical practice and research on trends in male sexual health parameters over time.
Topics Discussed
Sperm Quality Trends (4:00)
Dr. Eisenberg discusses the controversial topic of declining sperm quality over time:
- Some studies show a decline in sperm counts and quality over the past several decades
- Potential factors include environmental exposures, obesity epidemic, lifestyle changes
- Geographic variations exist in sperm quality around the world
- More longitudinal data is needed to fully understand trends
"I think if I were to say that I believe there's a decline, some of my colleagues and friends would be very upset with me. If I say I don't believe it, some of my colleagues and friends would be very upset with me." - Dr. Michael Eisenberg
Testosterone Levels (15:31)
The discussion covers trends and factors affecting testosterone levels:
- Evidence suggests average testosterone levels are declining over time
- Obesity is a major factor - fat tissue converts testosterone to estrogen
- Wide individual variation exists - some older men maintain high levels
- Environmental exposures may play a role in declining levels
"We do see great variation. I mean, I think just like you're saying, I usually let everybody know that usually testosterone peaks kind of early twenties, and it tends to go down probably 1% a year forever. But there are people that have very, very, very high levels." - Dr. Michael Eisenberg
Optimizing Sperm Quality and Testosterone (28:21)
Dr. Eisenberg provides advice on maintaining healthy sperm and testosterone:
- Avoid excessive heat exposure to the testicles (hot tubs, saunas, etc)
- Maintain a healthy body weight and overall health
- Be cautious with testosterone therapy, as it can impair fertility
- Consider sperm freezing if starting testosterone therapy
- HCG can help maintain fertility for those on testosterone
Lifestyle Factors Affecting Male Reproductive Health (36:57)
The discussion covers various lifestyle factors that can impact sperm quality and sexual health:
- Smoking is clearly detrimental to sperm quality
- Very high alcohol intake (20+ drinks/week) may negatively affect sperm
- Some recreational drugs can impair sperm quality
- Cannabis use may potentially affect sperm parameters
- Most common over-the-counter medications appear safe
Erectile Dysfunction Causes and Treatments (1:33:02)
Dr. Eisenberg explains the common causes and treatment options for erectile dysfunction:
- Only about 5-10% of cases are due to low testosterone
- Most cases are related to vascular/blood flow issues
- Oral medications like Viagra/Cialis work for 60-70% of men
- Other options include urethral suppositories, injections, and implants
- Addressing overall cardiovascular health is important
"I always tell men, as long as you have a p***s, we can always make it hard. There's a tremendous amount we can do." - Dr. Michael Eisenberg
Pelvic Floor Health (1:52:36)
The importance of pelvic floor health for male sexual and urinary function is discussed:
- Both overly tight and overly weak pelvic floors can cause issues
- Kegel exercises can be helpful for some men, but not all
- Pelvic floor physical therapy can be beneficial for various issues
- Pelvic floor muscles support the bladder, prostate, and sexual organs
Penile Length Trends (1:59:03)
Dr. Eisenberg discusses his research on trends in penile length over time:
- Data shows a slight increase in average penile length over past decades
- Reasons for this trend are unclear - could be related to earlier puberty or other factors
- Average erect p***s length is between 5-6 inches
"We did find that penile length has been increasing over time. So that was just sort of fascinating that we would see sort of in such a short interval of time that there would be a change." - Dr. Michael Eisenberg
Hair Loss Treatments and Sexual Side Effects (2:09:01)
The potential sexual side effects of hair loss treatments are discussed:
- Finasteride and similar drugs can sometimes cause sexual side effects
- Some men experience long-lasting issues even after stopping (post-finasteride syndrome)
- Younger men seem more susceptible to side effects
- The exact mechanisms of these persistent effects are not fully understood
Testicular Health and Cancer Screening (2:27:26)
Dr. Eisenberg provides information on testicular health:
- Average testicle size is about 16-20 cc (similar to a walnut)
- Men should be aware of any changes in size or texture
- Regular self-exams are no longer officially recommended due to anxiety/false positives
- Testicular cancer typically presents as a firm, painless mass
Conclusion
This wide-ranging discussion with Dr. Michael Eisenberg provides valuable insights into many aspects of male sexual and reproductive health. Key takeaways include the importance of maintaining overall health for sexual function, the complex factors affecting sperm quality and testosterone levels over time, and the various treatment options available for common issues like erectile dysfunction. Dr. Eisenberg emphasizes the value of baseline testing and being aware of one's sexual health parameters, even for young healthy men. The conversation highlights both concerning trends, like potential declines in sperm quality, as well as some surprising findings, like slight increases in average penile length over time. Overall, this episode offers a wealth of evidence-based information to help men better understand and care for their sexual and reproductive health.
