Marks Daily Apple
Serving up health and fitness insights (daily, of course) with a side of irreverence.
22 Jun

A Primal Primer: Testosterone

If you’ve been reading recently you know I’ve been on a hormone kick recently. That sexy looking molecule to the right and the hormone du jour: testosterone. Testosterone is the principal anabolic and sex hormone in humans, responsible for sexual desire and function, muscular hypertrophy, densification of bones, and hair growth. Compared to females, males famously produce about ten times the amount of testosterone, but females are far more sensitive to its effects. Though testosterone is largely responsible for those traits and characteristics that are considered “masculine” – physical strength, body hair, dominance, and virility – both sexes require it for proper sexual and physical development. In mammals, males secrete it primarily from the testicles (about 95% of the total amount, in fact) and women secrete it from the ovaries. A modicum is produced in the adrenal glands in both sexes.

Testosterone plays an important role throughout every stage of a person’s life:

Prenatally, testosterone – along with dihydrotestosterone, a more potent anabolic hormone – is partly responsible for the formation of the male genitalia. It helps determine gender identity (with society bringing up the rear later in life, of course) and it spurs development of the prostate and seminal vesicles.

In early infancy, boys’ testosterone levels rise, almost to puberty levels, only to plummet at 4-6 months. We’re still not entirely sure what the rise means and what all that testosterone is doing, but it’s definitely doing something. One theory is that the brain is being “masculinized.”

Immediately prior to puberty, testosterone begins to rise in both boys and girls. Childhood is departing, replaced by budding pubic hair, the beginnings of body odor, growth spurts, oily hair and skin, and that ridiculous peach fuzz above the lips that every eleven year-old male tries to cultivate and claim as facial hair. Bones mature and the arm pits grow hair.


During puberty, testosterone enjoys a massive increase.  Most of you reading this probably recall those awkward, exciting change-filled times: new odors, inconvenient fluctuations in the functionality and appearance of certain organs, strange new outlooks on the opposite sex. Good times. Thanks, testosterone!


In adults, testosterone’s effects on growth and development have largely manifested and maintenance becomes its province. Libido is preserved for both men and women and erection strength and frequency are regulated by testosterone. Muscles resist wasting thanks to T (and even grow larger).

I would be remiss if I failed to mention testosterone’s chief antagonist: cortisol. Cortisol, as you know, is one of the stress, fight-or-flight hormones. It kept us alive and our wits about us under short-term life-or-death situations for much of our evolution. Unfortunately, when cortisol is constantly elevated – as it often is in the sleep-deprived and chronically-stressed – testosterone is muted. Cortisol is catabolic (breaks tissue down), while testosterone is anabolic. Excessive levels of cortisol produce insulin resistance, fat gain, and muscle wasting, while testosterone promotes muscular hypertrophy and lean mass gains. Cortisol contributes to metabolic syndrome, while testosterone helps alleviate it.

Ironically, serum testosterone status seems to predict the cortisol response of people faced with victory or defeat. High T men and women who “lost” released more cortisol, the stress hormone; when they “won,” less cortisol was released. Low T folks’ cortisol changes did not depend on winning or losing. I guess that’s a downside to high T levels, technically, but it’s to be expected. I’m reminded of the Jimmy Cliff classic, “The bigger they come, the harder they fall”.

Low serum concentrations of testosterone are also independently associated with higher mortality rates in men, even when you consider other risk factors and preexisting health conditions.

Testosterone is important in the formation of bones, as I mentioned earlier, but it’s also crucial for the maintenance of bone density, especially in the elderly.

Testosterone aids in protein synthesis, effectively helping rebuild muscle fibers with amino acids. It can preserve existing mass or build upon it, creating more.

So, testosterone is important, and even vital, if you want to build (and keep) strong bones and muscles, maintain a healthy, active sex life, and live long and well into old age – but how do we make sure we’re making enough?

In 1889, a Harvard University professor by the name of Charles-Édouard Brown-Séquard injected himself with a “rejuvenating elixir” containing the extract of dog and guinea pig testicle, reporting increased vigor and feelings of well-being. Traditional Chinese herbalists would often prescribe dried tiger’s penis for impotence, and ancient Greek Olympians feasted on goat and lamb testicles to boost stamina and athletic performance. Clearly, even before testosterone was specifically identified, the ancients (and not-so-ancients) knew that the loins were involved in vigor, strength, and stamina.

Their (our) fixation on consumption of genitalia and genitalia extractions to correct deficiencies in strength, vigor, sexual stamina, and general “well-being” sounds intuitive, in a folksy, endearing sort of way. Does it make sense to eat bull testicles to restore one’s manhood and increase available testosterone?

Not really. Testosterone doesn’t pool up in one’s testicles. It’s not a static reservoir waiting in reserve to be disseminated throughout the body. It’s a hormone that the testicles (in men) and ovaries (in women) produce. That mouthful of fluid you got when biting into a roasted sheep’s testicle on your Greek vacation wasn’t pure, liquid testosterone – sorry. In order to get testosterone, you have to produce it (or inject it, but that’s an entirely different post) endogenously. And if you want to manipulate the amount of testosterone you have available, you can do it the same way you manipulate other hormones, like insulin, leptin, growth hormone, and cortisol. You tinker with your diet, your exercise, and your basic daily lifestyle.

Lift Heavy Things

Resistance training is a potent stimulant of testosterone production, so be sure to lift heavy things every now and again. If you want to tinker even further, messing around with rest intervals between sets can stimulate different hormonal responses. In one study, resting 90 seconds between squat and bench press sets boosted post-workout T levels the most, followed by rest periods of 120 seconds. Resting 60 seconds increased growth hormone the most and T the least.


In young men, a short six-second bout of sprinting increased serum total testosterone levels. Levels remained elevated during recovery. Interestingly, testosterone was also correlated with lactate levels in the blood. It would be even more interesting to know if any training that causes lactate levels to rise would also increase testosterone.

Avoid Excessive Cortisol

Since cortisol antagonizes and reduces free testosterone levels, and stress promotes the release of cortisol, avoiding stress becomes crucial for maintaining or boosting T levels. Make sure you get a good night’s sleep, every night (which in and of itself increases testosterone levels). Avoid overtraining, especially in the Chronic Cardio arena, which may affect T levels and reproductive function. And be sure to take time to chill out and relax (read a book, go for a walk, play).

Get Sun, or Take Vitamin D Supplements

Vitamin D, already associated with bone and muscular strength, also positively correlates with testosterone levels in men. Back in February, the vitamin D/T link got a decent amount of media attention.

Eat Clean, Pastured Animal Products

Toxic substances called dioxins have been shown to interfere with the male reproductive system, including production of testosterone. While concentrated sources of dioxins include Agent Orange (which I’m sure you’re already avoiding), we obtain most of our dietary dioxins through conventionally-raised animal products, especially animal fats and dairy (dioxins accumulate in fat). If you’re going to be eating fatty cuts of meat or using dairy, try to go for pastured, grass-fed animals to reduce your exposure and lessen the negative impact on your testosterone levels.

Eat Saturated and Monounsaturated Fat

A low-fat, high-fiber diet reduced serum and free testosterone levels in middle-aged men. T usage wasn’t affected, but T production was reduced. Another look at male athletes found that both saturated fat, monounsaturated fat, and cholesterol intakes were positively correlated with resting testosterone levels. PUFA intake was barely associated with increased levels.

Avoid Foods that Regularly Spike Your Blood Glucose Levels

Researchers found that 75 grams of pure glucose – and the resultant spike in blood sugar – was enough to drop testosterone levels by as much as 25% in a random grouping of healthy, prediabetic, and diabetic men. Now keep in mind how rapidly many SAD carb choices (pasta, cereal, bread, etc) convert to glucose upon digestion…

Get Adequate Zinc Intake

A zinc deficiency predicts lowered testosterone in men (eat your shellfish), but heroic supplementary doses of the mineral don’t boost T levels beyond normal in men with adequate dietary intake.

All in all, testosterone is an incredibly important hormone for health, longevity, and vitality – in both men and women. Leading a Primal life, free of excessive stress and peppered with smart, intense workouts, full of healthy animal fats and plenty of vitamin D, should be enough to promote adequate amounts of testosterone coursing through your veins. It may sound a bit redundant at times (advice: live Primal!), but what can you do when a common, uniting thread seems to run through almost every aspect of human health. It almost writes itself.

You want comments? We got comments:

Imagine you’re George Clooney. Take a moment to admire your grooming and wit. Okay, now imagine someone walks up to you and asks, “What’s your name?” You say, “I’m George Clooney.” Or maybe you say, “I’m the Clooninator!” You don’t say “I’m George of George Clooney Sells Movies Blog” and you certainly don’t say, “I’m Clooney Weight Loss Plan”. So while spam is technically meat, it ain’t anywhere near Primal. Please nickname yourself something your friends would call you.

  1. WOW – great stuff – If I order now for only $49.95 (plus S&H) can I get a book too?

    Mark wrote on June 23rd, 2010
  2. Rocking post – rocking comments!!

    sangita wrote on June 24th, 2010
  3. That is a very comprehensive review of the testosterone hormone. Great information about the effect of rest intervals during strength training and how tweaking that can boost growth hormones or testosterone.

    Paramjit wrote on June 24th, 2010
  4. The day I started working my legs HEAVY i.e. (Squats, Presses, Deadlifts, Lunges etc.) is the day I started gaining muscle everywhere. It was the missing link in my routine. Thanks T!!

    Erik wrote on June 24th, 2010
  5. The thing that stands out for me about this article is the correlation of cortisol and stress. In an effort to be well, I think learning to adapt, accept or advoid stess is key. For me, exercise has always been able to help relieve the stress of the day. Great article.

    Alicia Kirschenheiter wrote on June 24th, 2010
  6. I am hoping to gain greater balance in my hormone levels, and the first steps I have been taking is to go Primal as much as possible and quit with the birth control pills which was an 8 year course of convenience that may have been a hindrance to progress in the weight management and muscle gain department. I just stopped the pills… and I try my best to keep my carbs under 100g/day. My last problem is a stressful job that probably has produced more than its fair share of cortisol and exhausts the hell out of me, which pretty much keeps me from exercise most of the week. For anyone who has worked in food service it is a lot of stress and long periods of standing.

    Crystal wrote on June 24th, 2010
  7. Another influence on testosterone levels in both men in women might be social status. Increased pecking order position seems to result in heightened levels of testosterone production. Again this may be a chicken or egg scenario. If you status increases will your T level increase or does your status increase because of higher pre-existing levels of T. Both and either probably.

    Higher social status has also been linked to increased longevity
    “In the UK, a famous study called the “Whitehall Study” which examined government workers (all of whom had the same type of health care), found that the higher someone was in the hierarchy, the longer they lived. Recently, another study also showed the Nobel prize winners simply liver almost 2 years longer than people who were nominated, but did not receive a Nobel. This leads to the second theory, we’ll call it the “Hierarchy Effect,” which states that being lower in the social hierarchy independently impacts health through increases in the release of stress hormones. This has been shown fairly well in animal studies where researchers monitor the levels of stress hormones in primates and have found that being nearer the top reduces the overall level of stress hormones (but note that being at the top actually increases them because the top chimp must continually defend his position).”
    Thanks for a great post Mark

    mark tyrrell wrote on June 25th, 2010
  8. I have read that cetain foods boost T-levels. I think it was Salmon, Celery, Avocados… not sure about this. Anyone?

    warren wrote on June 25th, 2010
  9. About two years ago I found that I hit a training ‘sweet spot’ and have struggled recently to produce the same results. What I didn’t do at the time was keep a diary of my training, diet and supplements. Though I do recall it pretty well, it was all fairly primal.

    So it was only recently that I remembered I had bought a bottle of ZMA as an impulse buy and had taken three tablets before bed each night. At the time I had changed several other factors of my training and so I never put any of the results down to the ZMA. Once the bottle had finished I never gave it another thought. Until now that is. Having replicated the training but with a stubborn 14lbs of fat left to go. I have bought another bottle and I am already impressed. Although it’s too early to calculate my gain in lean muscle mass, I feel that I am training harder and my libido is through the roof. That is a pretty simple and conclusive indicator in my book.

    Here I should mention ZMA only corrects the depleted minerals needed for T production. It also helps reduce cortisol and improves sleep. Well at least that’s what it claims. Now that I discovered that testosterone was the missing ingredient, I have also bought Tribulus which is a natural herb that also helps increase T production. Though this doubling up of supplements is not very scientific and I would probably be best to try both of them separately as controlled experiment I am at least happy to be making progress again. So I wonder what you think Mark to these supps?

    Craig wrote on June 26th, 2010
    • I have seen a “boost” with ZMA as well. In my case…the brand that I bought had ingredients in it that effected my dopamine levels…which is what I attributed to some very odd dreams while taking it.

      Other suppliments that have help me include Maca and Tribulus…but that’s just me.

      Phil-SC wrote on June 26th, 2010
  10. Another huge +1 for ZMA. It is merely zinc combined with Magnesium Aspartate (one of the best forms of magnesium). It is a great way to get Zinc and Magnesium in one place.

    Your sleep quality will improve and your T levels will increase, guaranteed.

    Keenan wrote on June 29th, 2010
  11. So testosterone is this great magical hormone that keeps us healthy but when a baseball player uses extra amounts of it to run faster and hit farther he’s a cheater? and it’s an evil illegal drug and the scourge of youth and we must protect the children (from a chemical already in their body keeping them healthy).

    Xander wrote on June 29th, 2010
    • You miss the point. Supplemental testosterone goes BEYOND what is normal for most men. In addition, it can have disastrous consequences in destroying natural testosterone levels.

      When a guy supplements with testosterone, his body recognizes that he is getting his hormone requirement from a different source and begins to shut down natural production sources. When he goes off the supplemented test, he is all but dry. And when the body shuts something down, it’s EXTREMELY difficult to turn it back on again.

      Pat wrote on January 5th, 2012
  12. I’ve tried absolutely everything to increase testosterone naturally. As of now, I still haven’t found that magic something. No wonder why bodybuilders and professional athletes find no other way than to take steroids.

    Jack Strawman wrote on July 5th, 2010
    • Science has proved things like high sat and mono fats help, zinc may reduce aromatase activity, etc. But when you put numbers to it, say those changes increase your T by 100% (which is unlikely), going from 200 to 400 isn’t really going to get you swole. You might feel a little better, but visually seeing results at those incremental differences would be unlikely.

      MikeD wrote on March 6th, 2011
  13. Can you produce evidence that organic food has less dioxins than conventional?

    Some studies out there show that dioxin content is the same between organic eggs and conventional.

    Papa Hemingway wrote on November 23rd, 2010
  14. I have type ii diabetes (since 1995 or 6). Metformin 1000mg bid was causing me tremendous cramping followed by bouts of diarrhea. Sex drive was in the tank..”wood” was something burned in a fireplace. Recently went to naturopath and he advised strict Adkins plan plus supps that were basically versions of chromium picolinate. Advised slow walking, no other exercise. Long story but there is a point. I went to a different doctor and he put me back on metformin (500mg bid) glimipiride (4mg) bid and single doses of levathyroxine and lisinopril. Recent readings of fasting and evening blood glucose have been in the low 100’s with one reading of 97. Doc said that the hypothroid could be contributing to lack of weight loss even though I am active and am exercising 3 to 4 times a week. My biggest concern and the subject of this thread is the ED. I have tried the pills and even investigated caverject or its Boston Medical equivalent. Is the ED reversible or will I need to check out the drugs again? I am 57 years old and have seen the decrease in erectile function over the last 3 years. Should I investigate the natural supps for this issue? Also the lisinopril has some concerns for me. I know this is long but I could use some direction.

    Ipphoneguy wrote on February 9th, 2011
    • Glimipride is Amaryl (glimepiride), Glyburide, (Glucovance is glyburide with added metformin)
      Glucatrol, Diabeta (glipizide) Sulfonylurea. Stimulates beta cell to secrete insulin for 8 – 12 hours whether or not glucose is present in bloodstream Raises insulin level Stimulate receptors on heart tissue leading to higher rate of heart attacks by 33%

      Raises insulin levels! That is more dangerous than raising blood sugar.

      Eat Primal, low carb, under 50 grams of non fiber per day. Become a ketone burner instead of a glucose burner.

      BUT FIRST..educate yourself and SLOWLY wean yourself of the meds as you eat lower and lower carb.

      Read Dr. Bernstewins book “DIabetes Solution” give a copy to your doc. Go to my blog…Diabetes is

      Lets get you healthy first then your T will come online.

      Andre Chimene wrote on January 9th, 2014
  15. You are missing the 2 most important things which are avoid alcohol and caffeine completely. Like this, one doesn’t have to worry about carbs so much, and will experience much less cravings for them anyway.

    Lose the poisons, lose the diet neurosis and supplementation/aggressive exercise nonsense.

    Not easy to do as these are both highly addictive, and widely consumed in our sick society, but worth it.

    good luck

    tom wrote on May 23rd, 2011
  16. Very helpful article…thank you

    Adrian London wrote on July 27th, 2011
  17. Once I initially commented I clicked the -Notify me when new feedback are added- checkbox and now each time a comment is added I get four emails with the same comment. Is there any way you may take away me from that service? Thanks!

    ny voip wrote on August 11th, 2011
  18. Does masturbation affect our health plzz reply?

    ddt wrote on October 8th, 2011
  19. does masturbation affect health?? plz reply

    ddt wrote on October 8th, 2011
  20. Does having a lot of sex cause an increase in T? I wonder, because at 38 now, I still feel and look young…lol

    Ben wrote on October 10th, 2011

Leave a Reply

If you'd like to add an avatar to all of your comments click here!

© 2016 Mark's Daily Apple

Subscribe to the Newsletter and Get a Free Copy
of Mark Sisson's Fitness eBook and more!