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. Eat clean, excercise, stay away from all the sugary crap, THINK your way to strength and get in the gym and work your butt off! There really are NO SHORTCUTS. Tosca Reno has a great book for men (there’s also a ladies version) to help you get and keep TRULY lean and fit. Jack Lalanne and many others would agree: 90% of the equation is CLEAN EATING. The rest is hard, hard work, but we love it don’t we?!
    Hope everyone enjoys their workouts. Blessings!
    Mr. Clean Gene
    Halifax, Nova Scotia

    Gene Collins wrote on October 29th, 2011
  2. Just thought I would tell my story. At the age of 42 my T levels were in the low 3’s. The doctor prescribed Nebido injections (long-acting testosterone undecanoate). After a year my T levels rocketed to the mid 6’s, I looked and felt great… right up until the time I started to notice HAIR LOSS! Being a vain MF I stopped COLD effing TURKEY and started slathering on Minoxidil to arrest the hair loss problem, which seems to have more or less worked.(!) Stuff is pretty miraculous. Aside from indulging in that fairly toxic topical medication, I started living primally to cope with what I was told would be a hideous onslaught of depression and muscle-wasting. Yeah, I did lose mass. Yeah, my T levels plummeted to a 2.3. But after a year I am doing okay, and I kept my hair. My T cells are at 3.9 so they are inching up. I am told that I could combat the DHT-related hair-loss issues caused by the Nebido by taking Propecia. But I am not jazzed about these synthetic solutions, and countermeasures, and dependencies. I miss the injections and having a little better physique but you can’t always get what you want… That said, I will eventually supplement with injections — but only after I have really done everything I can to go natural. I am 44 tomorrow and hoping I can hold off until I’m 50.

    Mari-O in Bangkok wrote on November 1st, 2011
  3. i am a 17 year old guy and i have very less body hair what should i do to increase it?

    rony wrote on November 6th, 2011
  4. Hi Mark,

    I’m looking for information on testostorone that you may be able to help with or perhaps point me in the direction to continue searching.

    Specifically, I am trying to find out if the production of testostorone can be changed/increased at an early age by external stressors such as child abuse.

    There are many studies that show violent adults have high testostorone, but in paralel research, I have noted that abuse victims show attributes of high T after the abuse and low T prior.

    Thanks for any comments.

    Brandi wrote on November 10th, 2011
  5. I’ve been browsing on-line greater than 3 hours these days, but I by no means found any fascinating article like yours. It’s pretty value enough for me. In my opinion, if all web owners and bloggers made good content material as you probably did, the web can be a lot more useful than ever before.

    What is best anti aging products ? wrote on December 12th, 2011
  6. i really like this knoledge about teststrone. it will help to solve people problems

    ashwani wrote on January 21st, 2012
  7. hello i am 22 years(running year) old.i am 5.5 tall.i still want grow to taller by at least 2 inches or say 5 cm .what should i do?
    i am doing yoga and few stretching exercise .is this enough ? what else can i do? i want do not want to take any tablet or medicine ,as my parent does not allow me to do so.please help me .i will be grateful to you all.

    Ravikumar gupta wrote on January 25th, 2012
    • are you a guy or girl? also, yoga and stretching is not enough. lift hard and rest harder. as ridiculous as it sounds, look up natural bodybuilding. this in turn (if done correctly) should burn fat and build muscle. 6-7 small well portioned meals a day with PLENTY of protein and complex carbs. also, a lot of water and sleep. Sooo much water than you think…

      Trevor wrote on September 1st, 2012
  8. i didn’t understand the no caffeine thing mentioned by someone. Is caffeine bad for testosterone? I’m starting to get depressed, looking at everything i love that may effect test. I’m 43, really fit, bike/run/lift weights, and eat really well (overall). My testosterone level came in at 270. Not good, right? (have yet to go back to doc). One thing that has not been mentioned – my wife and i are late on trying to have kids. Can test replacement therapy impact that? i hear it can, but wondering if a “low dose” of the gel might help me. I feel really good overall, but my libido is kinda lame…

    the beer thing is depressing – i LOVE hoppy beers like IPAs. I don’t go crazy, but it really is my only indulgence, and i partake. Sugary desserts i have no problem with. So now i’m depressed after reading the hops/estrogen connection :(

    T wrote on February 3rd, 2012
    • what have you done after finding out about low T? I am 43 and in the low 300s.

      brian wrote on January 21st, 2013
  9. take dates honey eggs green tea garlic ginger vit.E milk 25mg viagra(sildenafil citrate)yoga exercises can be best for normal sex life

    amjad wrote on February 5th, 2012
    • You can also take ginseng to get sildenafil citrate in its natural form. It is a vasodilater.

      Animanarchy wrote on February 5th, 2012
  10. I just inject testosterone. Makes me big and strong :-)

    Jojo wrote on February 28th, 2012
  11. This is an awesome list and exactly what I needed. I’ve been trying to brainstorm a list of generating more testosterone naturally for an upcoming post. Excellent writings as always :)

    Nick wrote on March 25th, 2012
  12. This is a really interesting topic with great comments. All seems logical to me, just putting in practice is always the challenge due to the day to day stressors that we all live with.

    Dennis wrote on May 24th, 2012
  13. Mark what are your testosterone levels? Are they above average for your age?

    With all due respect,


    Avishek Saha wrote on June 1st, 2012
  14. What’s up Risso? You all need to gizzo! that is because i sidzo! LOL dumbass

    glen wrote on June 8th, 2012
  15. Testosterone is the most important hormone in our body influencing the development of muscle mass (in a womanly way in women and a manly way in men), bone density and sex drive. healthy diet, regular exercise and sexual intercourse will increase your testosterone,

    jennifer wrote on June 13th, 2012
  16. so uhm, had a complete blood levels scan done a couple days ago, found out i have very high levels of alot of good things, testosterone being one of them, i have 85% more testosterone then most males at my age, which i found to be really high, my doctor said its not a bad thing and asked about my eating habits, and now hes stumped, so iv been researching reasons i could have such high testosterone levels with poor eating habits, not much heavy wieght lifting, etc, and i cant figure it out, could anyone either explain to me or post a link on reasons i could have such high testosterone?

    phoenix wrote on July 8th, 2012
  17. Than you for posting this. My doctor told me I have a low testosterone level and suggested a testosterone gel. But I read about it and fear the side effects. I know I am often stressed and cheat on my sleep time. I know I don’t exercise enough and am already low in Vitamin D. I need to lose about 15 pounds. All in all, I need to get up and do stuff. Just want to thank you for posting this. It makes me feel better knowing what I need to do instead of having to apply some expensive prescription that may have harmful side effects in other parts of my life.

    Robert LeParc wrote on July 16th, 2012
  18. A recent Japanese study found that vitamin K2 (MK-4) increased testosterone production in rats and concluded that supplementation could reduce down-regulation of testosterone production in the elderly. (PMID 21914161)

    Jack Cameron wrote on July 16th, 2012
  19. If you read it closely, it says that women are just more sensitive to testosterone. Women who lift weights are just healthier. Their bodies don’t bulk up like men, because the bodies react to just a little testosterone and the cycles of hormones change throughout the month anyway, flushing things out so there is more sensitivity to less, because it is not always at high levels. It ebbs and flows much more than men. See estrus, for more detailed info.

    Nicholas wrote on July 30th, 2012
  20. Bottom line, just eat fresh food,exercise everyday,enjoy the sun,take sum zinc and have sex as much as possible. Do active and fun things that make you HAPPY! Be well!

    Reyne wrote on August 1st, 2012
  21. hi. i cant get pregnant because of my high testosterone level of about 0.152ng/ml how can i lower this hormone so i can get pregnat. thanks

    izza wrote on August 23rd, 2012
  22. im 33 and i have 0.152ng/ml testosterone and this cause me not to get pregnant for 8yrs…. how can i lower the testorerone level and how to improve my female hormone…pls help me

    izza wrote on August 23rd, 2012

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