This long article by Olli Sovijärvi was originally posted in Ben Greenfield‘s website. Here is the story behind it:
“So finally, when I got the text above, I told Olli,”
“Look man…most people have no clue you can shine laser lights on your balls to increase your testosterone, or that there are ways to reverse the damage cell phones can wreak on your gonads, or that once you drop below 30% carbs your testosterone starts to severely decline if you’re an avid exerciser…
…so, can you write an article for me with all these tactics?”
– Ben Greenfield
Read more https://bengreenfieldfitness.com/2016/09/how-to-biohack-your-testosterone/
Introduction – Most Testosterone Advice Sucks
Biohacking testosterone (aka “T”) has been a hot topic past few years, or decades, or centuries. For example Youtube is full of T-otpimizing podcasts and channels, iTunes has entire podcasts devoted to libido and testosterone, broscience forums are chock full of T advice from around the planet.
You also can find plenty of articles on optimizing T in the web and even bunch of (great) e-books have been released. I have read and studied all of them and beyond. Many relatively promising supplements, pills and tricks sound good but simply don’t work.
I am very grateful for the amazing work on optimizing testosterone put out by guys behind the Anabolic Men -site (especially Ali Kuoppala) from whom I have learned a lot. Thanks also for Christopher Walker, a neuroscientist, who has written a significant amount of information on testosterone, especially training wise (e.g., THOR, Testosterone I/O, Testshock, etc.). I also want to thank a bunch of Finnish guys who have been releasing T-optimizing booklets and reviews. Still, these tricks presented later in the article I have had to dig deep from the depths of Pubmed and literally spent hours and hours of reading every possible study that could potentially find something new on one of the most important hormones there is for men.
Before we jump into these many-probably-never-heard-of-biohacks on optimizing your T, I want to make clear that you have the basics covered. Without adequate training, nutrition, sleep and stress management these tricks won’t be as solid as they could be. You can read more about optimizing sleep, nutrition, stress and exercise from Biohacker’s Handbook.
The Testosterone Basics
Testosterone is an anabolic sex steroid hormone, which is mainly released in Leydig cells of the testes (95%). Testosterone is not just a male hormone, women also produce it in the ovaries but of less magnitude. Men have roughly about 10 times more testosterone than women.(1) Testosterone is derived from cholesterol, ”The mother of all steroids”.
Testosterone is responsible for mens sexual characteristics: it stimulates the growth of penis and scrotum, increases growth of body and facial hair (which is otherwise highly genetically regulated; so little body hair doesn’t automatically mean low T), impacts an ability to put on muscle mass and lose fat and even affects the tone of the voice by strengthening vocal cords.
Testosterone is also an anti-aging hormone, which means that a healthy level of testosterone throughout your life can make you live longer.(2) In men aged 30 years and older, testosterone levels steadily fall at a rate of about 1% per year.
Physiology of Testosterone
There is a feedback loop from brain to testes, which controls how much testosterone is being released. The physiological regulation of testosterone begins in hypothalamus which releases gonadotropin releasing hormone (GnRH). That stimulates the pituitary gland to release two crucial hormones for male health: follicle stimulating hormone (FSH) and luteinizing hormone (LH). In the testes FSH stimulates spermatogenesis (making new sperm cells) and LH stimulates testosterone production. In turn, testosterone exerts feedback control of the pituitary LH and FSH secretion. Depending on the tissues, testosterone can be further converted to dihydrotestosterone or estradiol.
Produced testosterone enters the blood stream as free testosterone, which is biologically available. Majority (c.a. 98%) of the produced testosterone is then bound to sex hormone binding globulin (SHBG) or albumin (another major protein in the blood). For testosterone to become ”active” you want a release of it from the carrier protein and an optimal SHGB levels in the blood.
For testosterone to have an anabolic effect in the body it must bind to an androgen receptor for example in the muscle tissue. Strength training activates these receptors and bioavailable testosterone is then able bind to free androgen receptor sites. After that begins a cascade in the cell which eventually enters DNA and starts protein synthesis. Therefore it is crucial to have a good androgen sensitivity and density (see later hacks for that).
Testosterone is also a hormone that plays a key role in carbohydrate, fat and protein metabolism. That is why it has a major influence on body fat composition and muscle mass, especially in the male. Research has over and over again shown that testosterone deficiency is related to various metabolic health problems: increased fat mass (central adiposity), reduced insulin sensitivity and glucose tolerance possibly leading into metabolic syndrome, type 2 diabetes and even cardiovascular disease (CVD).(3) Testosterone deficiency has been reported in population studies to be associated with an increase in all-cause mortality (mainly linked to CVD).(4) Healthy levels of testosterone also protect from cognitive decline.(5)
Basic life-style hacks for high testosterone
1. Sleep enough — often more is better
The majority of the daily testosterone release in men occurs during sleep. Fragmented sleep and obstructive sleep apnea are associated with reduced testosterone levels. A study released on The Journal of the American Medical Association, found out that one week of sleep restriction (5 hours of sleep per night) decreased testosterone production by 10–15%.(6) Studies have also found out that sleep’s effect on testosterone has an inverted U-shaped curve. Testosterone production increased with increasing sleep duration up to 10 hours after which it decreased.(7)
For ultimate sleep hacks, check out Biohacker’s Handbook’s sleep chapter for free here:
2. Get rid of extra belly fat and be lean
It is generally noticed via research that the higher your body fat percentage the lower the testosterone. The correlation works especially into direction that getting leaner will rise your T levels.(8) ”Longitudinal analyses showing no influence of baseline hormone levels on change in anthropometric measures imply that body composition affects hormone levels and not the reverse.”(9)(10) It has been roughly estimated that a male body fat percentage between 8–14% is optimal regarding testosterone production. Higher fat mass also usually increased aromatase enzyme activity, which converts more testosterone into estrogen.(11) In opposition, too low body fat content can be detrimental for testosterone production.(12)
3. Practice strength training and gain some muscle mass
While practicing strength training and gaining muscle often reduces body fat percentage (which leads into higher testosterone) it also has independent effect on elevating testosterone.(13) Having higher muscle mass is positively correlated with higher testosterone. By lifting medium-heavy weights explosively can stimulate short-term and long-term testosterone production.(14)(15) Training progressively will force your body to adapt to higher and higher testosterone levels via neuromuscular adaptations.(16)
Follow these principles when strength training for optimal T production:
- Always lift explosively (with perfect form)
- Lift heavy enough, but not too heavy (to have an optimum force/velocity-curve)
- Use compound lifts to activate large amounts of muscle mass
- Focus on body parts that have high density of androgen receptor sites (chest, shoulders, trapezius)
- Do sprint intervals to maximize force production in minimal time and to activate fast-twitch muscle fibers
- Do as much work on as much muscle tissue as possible in as short amount of time as possible while staying under the negative stress threshold
- If your gym is limited, the muscle up exercise is, in my opinion, the king of testosterone-boosting exercises
4. Control your stress levels and meditate
Chronic stress leads eventually into chronically elevated stress hormone (cortisol) levels in the blood. Cortisol is necessary for life, but when excreted too much for too long, it can cause some serious health problems. One of the disadvantages is diminished testosterone secretion, as cortisol and testosterone compete of the same hormonal precursors and raw materials (mainly pregnenolone).(17)(18) For example in military conditions prolonged stress has been shown to significantly lower testosterone secretion.(19)
Implement these well researched strategies into your life to lower stress (my favorite ones):
- Meditation (in particular) (20) and relaxation exercises such as deep breathing (21)
- Spending cell-phone free time in the nature and walking (22)
- Eating enough whole-food carbohydrates (especially in the evening and when having an intense period of exercise) (23)(24)
- Adaptogenic herbs (ashwagandha in particular) (25)
- Vitamin C (the more stress the more vitamin C) (26)(27)
- Phosphatidylserine (28)(29)
5. Eat nutrient dense whole foods and get enough (but not too much) calories
Getting enough and optimal amount of micronutrients is crucial for testosterone production. Measuring your micronutrient status is a crucial step on finding out what your exact situation is. The most important micronutrients for testosterone production are zinc, magnesium, calcium, vitamin D, B vitamins, iodine, selenium, vitamin K2, vitamin A, vitamin E, manganese and boron.(30) Eating a diet rich in nutrients and minerals (read: whole foods) is crucial not just for overall health, but also for optimal T production. Getting a multivitamin supplement on the basis of your personal needs can also be a testosterone saving thing if your diet is lacking something.
The body needs enough calories to produce adequate amounts of testosterone. With constant and prolonged calorie restriction the body begins to adapt into survival mode, which means that for example reproductive system is not of great importance anymore.(31) The body will conserve energy for vital processes and internal organs.
For optimal testosterone production it is wise to eat at maintenance or a slight calorie surplus. BUT, according to: http://garciniacambogiatopic.com/buy-dr-oz-diet-pills, if you are overweight, a minor calorie deficit and losing weight will actually elevate testosterone production (as explained previously). So, the plan is to get lean first and then eat higher calories for optimal testosterone production and maintenance. Losing weight slowly is a good option here: about 15% calorie deficit doesn’t seem to affect testosterone negatively. But it can affect somewhat negatively your thyroid hormone production.(32)
When it comes to macros, nearly everybody especially in the fitness industry, talks about protein. There are tons of different protein supplements that are supposed to make you lean and fit. Protein has gained a reputation, that it is the most important macronutrient what comes to building muscle and gaining strength. It is true that protein and especially certain amino acids are essential for life and muscle tissues and that chronic protein malnutrition will cause low testosterone levels.(33)
The caveat here is that you don’t actually need as much protein as you have been told. For most, the recommended daily allowance levels (1.0–1.4 g /kg of bodyweight) are enough for optimal testosterone production. For strength training individuals often recommended protein intake is 1.6–1.8 g / kg of bodyweight. Even athletes that practice strength training do not benefit from extra protein intake (over 2.0 g / kg of bodyweight).(34)
Protein source is also a major factor in testosterone production: a study published in British Journal of Nutrition found out that for example when meat was replaced with soybean protein in healthy men, their testosterone:estradiol ratio decreased significantly.(35)
For optimal testosterone production it seems crucial that you don’t eat too much protein and that you eat enough carbohydrates and fat. One study which compared protein and carbohydrate changes and their hormonal effects found out that when the male subjects went 10-days on a high-protein low-carb diet, their total testosterone levels were 21% lower than what they would have been on a high-carbohydrate low-protein diet. The high-protein diet also caused significantly higher cortisol levels. The diets were equal in total calories and fat.(36)
Another study, which compared ratios of protein to carbohydrates to different fats, found out that diets higher in carbohydrates and saturated+monounsaturated fats than protein were related to higher testosterone production in strength training men.(37) Previous studies have also found out that men who consume a diet containing 20% of fat compared with diets containing 40% fat have significantly lower concentrations of testosterone in the blood.(38) Many other studies also show that getting enough fat from diet is crucial for testosterone production.(39) Also getting enough cholesterol (raw material for steroid hormone production) from diet is critical to optimal hormonal balance.
For men who exercise and especially perform an intensive training micro-cycle it is crucial to eat enough carbohydrates (CHO) to optimize testosterone production. In one study two groups (30% of CHO vs 60% of CHO) were compared in terms of testosterone-to-cortisol-ratio. The study found out that those who ate 60% of carbohydrates had significantly higher free testosterone to cortisol -ratio than the lower carbohydrate group.(40)
The bottom line is this: for optimal testosterone production you shouldn’t go too low in calories (neither too high), shouldn’t consume too much protein (under 2g/kg) or eat too little carbs and too little saturated and mono-unsaturated fats. For me personally the optimal ratio for T production seems to be on a 2500 kcal/day slight deficit (-20-25 % for anti-aging qualities) diet with 98 kg bodyweight looks like this :
1.8g protein/ bodyweight (1.8g x 98 = 176.4 grams = 720 kcal)
40% of total calorie intake fat (1000 kcal = 111 grams)
Rest of the daily energy need from carbohydrates ( 780 kcal = 195 grams)
That means also eating quite a bunch of carbohydrates and still this could be among conventional nutrition advisors called as a ”low carbohydrate diet”.
note: I do every now and then calorie surplus days not to go too low on weekly average calories
You can read from the Anabolic Men’s site the scientific basis for the most important foods that boost testosterone production:
Based on that, here are my top 12 foods that satisfy the criteria above:
Grass-fed beef & lamb
Extra virgin olive oil
Dark green leafy vegetables
Pastured organic eggs
Dark berries such as bilberries
Raw cacao & chocolate
+ bonus: Celtic sea salt & high-altitude single-origin water-washed coffee
I would suggest that you check out Biohacker’s Handbook’s Nutrition chapter for more information on how to optimize your personal diet.
6. Drink enough water and hydrate yourself
Getting enough water is not only crucial for life but also for optimal hormonal balance. For example just a mild dehydration (1–2%) can raise cortisol levels and thus effect testosterone production. Especially when sweating a lot and during exercise the importance of drinking water is increased.(41) The higher the dehydration the bigger the effects are on raising cortisol (and adrenaline) and lowering testosterone.(42)
On the other hand, drinking too much will also cause problems such as diluting the blood and messing up with sodium balance in the body – even leading to hyponatremia (more precisely hypervolemic hyponatremia) which, when severe, can cause numerous neurological and cardiovascular symptoms.(43) If you drink a lot, use also sea salt to prevent water retention and electrolyte disturbances.
The easiest way to estimate your hydration status is to analyze the color of your urine and the feeling of thirst. If your urine is diluted and pale in color, you have probably drank too much water. Also, if you feel a serious thirst, you are already in a state of mild dehydration.(44)
7. Have regular sex, but don’t ejaculate too often
There hasn’t been conducted any really convincing studies on sex frequency and testosterone correlation in young men. However, one big observational study conducted with 1226 older men (aged 70+) found out that regular sex helped to diminish the decline in testosterone level that occurs naturally with age. The study says:
”We found a consistent association among older men followed over 2 years between the decline in sexual activity and desire, but not in erectile function, with a decrease in serum T. Although these observational findings cannot determine causality, the small magnitude of the decrease in serum T raises the hypothesis that reduced sexual function may reduce serum T rather than the reverse.”(45)
One small study found out that men having sex in a sex club had an average increase of 72% of salivary testosterone after sex. Those masturbating and watching sexual acts raised T only by 11 percent.(46)
One sexual performance anecdote, mainly from well known athletes, is that sex previous day or even many days before competition hinders athletic performance. But, this topic has actually been researched and busted as a myth.
For example, one study comparing the maximal effort on cycle ergometer found out that having sex 2 hours before athletic performance slightly diminished recovery capacity, while having sex 10 hours before the event had absolutely no effect on performance or recovery.(47) Another study found out that having sexual intercourse 12 hours prior to maximal treadmill effort didn’t have any negative (nor positive) effects on performance.(48)
On the other hand, in traditional Chinese medicine it is a common knowledge that ejaculation turns over Qi (Chi), your life force. This also makes sense, since sperm contains the seeds of life and lots of minerals. Luckily, this topic has also been research by scientists.
One study found out that a short-term abstinence of sex (3 weeks) slightly increased testosterone.(49) Another small study (28 healthy men) could actually verify, that an optimal ejaculation frequency for men testosterone-wise is 7 days. The study found out that on the 7th day of abstinence there was a significant increase in testosterone production (146%).(50) Too long abstinence (e.g. over 3 months) can crash your testosterone production.(51)
So drawing all these together it seems that having sex once a week with a real partner is the best way of elevating your testosterone production.
8. Avoid exposure to endocrine disruptors in plastics, food & water
Endocrine disruptors are synthetic chemicals or natural substances that can alter the endocrine system. Many of the endocrine disruptors are either directly negatively affecting testosterone production or acting as estrogen mimics (like xenoestrogens). These are mainly found in plastics, metal food cans, detergents, flame retardants, toys, pesticides, preservatives, cosmetics and pharmaceuticals.(52) They have also been linked to many other health problems like cancer, decreased fertility, metabolic syndrome, hypothyreosis and diabetes.(53)
Avoid these substances:
- BPA (Bisphenol A)
- Found in plastics; can lower testosterone levels significantly and cause erectile dysfunction
- BPS (Bisphenol S)
- Marketed as a ”safer” alternative to BPA found in thermal receipts, plastics and household dust.
- Has the same negative endocrine effects as BPA
- Found in plastics and cosmetics
- Men having high phtalates in the urine have lower testosterone levels
- Found especially in sun lotions, moisturizers, shampoos, tooth pastes and in other cosmetics as a preservative
- Function as a xenoestrogen in the body elevating estrogen levels in men (and women)
- Triclosan & triclocarban
- Found in antibacterial dilutants, soaps and hand sanitizers
- Can lower testosterone levels in men by disrupting biosynthesis of testosterone in Leydig cells (54)
- Benzophenones (BP-1, BP-2 & BP-3)
- Found mainly in sunscreens functioning as UV filters
- Can possibly lower testosterone by antagonizing androgen receptors (in English, blocking the receptor sites) and blocking enzymes converting other androgens to testosterone
Reduce your exposure to endocrine disruptors by following these strategies:
- Avoid the use of plastics as well as you can
- Switch plastic cups to glass or steel cups & bottles (glass would be optimal)
- Store leftover food in glass jars
- Aquire a good tap filter that filters all contaminants and endocrine disrupters (e.g. reverse osmosis & activated charcoal filters)
- Use only organic & natural ingredient cosmetics
- Avoid junk food and prefer organic food
- Minimize the handling time with receipts or use gloves
- Avoid the use of detergents and flame retardants (and other possible endocrine disrupting chemicals)
9. Raise your basic physical activity but don’t do too much endurance training
Being physically inactive is deleterious to your testosterone production. It has been shown in various studies that sedentary men who engage in regular physical activity raise their testosterone levels significantly.(55)
For example a 12-week period of increased physical activity in a group of obese men showed significant increase in testosterone levels independent of accompanied weight loss induced by a mild calorie deficit.(56) This means that a basic low-level physical activity like walking is an independent testosterone boosting factor. On the flipside,too much endurance training has been shown to lower testosterone levels significantly.(57) One interesting fact is that in endurance athletes low T is an independent factor (possibly impairing testicular function) which is not related to chronically elevated cortisol levels.(58)
10. Increase your androgen receptor density
Besides optimizing testosterone production for optimal actual hormone signaling you need to have a good amount of androgen receptors in your body. Here are some the most researched ways to increase your androgen receptor density.
Intermittent fasting (IF) and longer fasts
The easiest way to prone your androgen receptors for optimal testosterone uptake is intermittent fasting. Simply skipping your breakfast and pushing the first meal of the day as far as you can is a method that works very well. A small study showed that a fast of 12 to 56 hours improved testosterone response up to 180% in lean, but not in obese men.(59)
Another study found out that after 10 day water fast their testosterone had a downward trend of approximately 15–20%. When re-feeding after the prolonged fast with normal meals the participants’ testosterone levels went up significantly higher than before the fasting baseline values. One guy even went from around 600 ng/dl to 1600 ng/dl.(60) The explanation for this phenomenon is that fasting primes your body to be more receptive of testosterone which means higher androgen receptor sensitivity.
Warning: If you are under a chronic stress and have super high cortisol levels all day long, a prolonged fast might not be your thing.
Coffee (especially when fasting)
Coffee blunts hunger, which makes fasting easier. The caffeine in coffee can raise testosterone levels before exercise especially when tired (4mg/kg dosage) (61) and after exercise (240 mg dosage).(62)
Explosive resistance training
There are basic resistance training principles that you want to follow to optimize your androgen receptor density. First, activate large amounts of muscle mass with big compound movements. Second, do every movement as explosively as possible while maintaining a proper form. Third, keep workouts intense and short to avoid excess cortisol release. Fourth, use progressive loading with training (e.g. microloading).(63) Men who do resistance training regularly have higher androgen receptor density than untrained men.(64)
Carnitine in is a lipid transporter molecule which moves ingested dietary fat via carnitine-acyl-transferases into mitochondia to be oxidized into energy (beta-oxidation). It will also increase androgen receptor activity in cells by providing energy for the receptors.
A 3-week supplementation with 2 grams L-carnitine L-tartrate (LCLT) per day has been shown to upregulate androgen receptor content after exercise, which promotes better recovery from training.(65) Another 3-week supplementation study showed that LCLT reduced the amount of exercise-induced muscle tissue damage, which also meant that a greater number of receptors would be available for hormonal interactions.(66)
Other potential substances
Based on in vitro and animal studies Mucuna pruriens, which contains L-dopa (3–6 %) has a potential of increasing androgen receptor density.(67) I would still be careful with this, because overusing L-dopa may have some side effects such as hypotension, nausea, disorientation and sleepiness. These are more likely if you just use L-dopa medication instead of Mucuna pruriens. One study conducted in humans found out that Mucuna reduced stress and improved sperm quality in infertile men.(68) Similar findings have been seen in a few other studies as well (in infertile men).
If you are asking yourself, should I use forskolin for better results? Based on in vitro studies, Forskolin, which functions as a cAMP activator and further as a PKA stimulator, can stimulate also the density of androgen receptors.(69) There is also a placebo-controlled human study on Forskolin on its effects on recovery and testosterone production.(70) The study has been critizised by many because of the authors’ interest in supplement business and by providing their own product. Forskolin may also cause hepatic side effects if the dosage is too high for too long.
Here is a conclusion on Forskolin drawn together by Suppversity:
”…the almost non-existent human data on the purported testosterone boosting effects, this should be reason enough not to buy more than one bottle for a test-run. After which I highly suggest to do some lab work to see if whatever good or bad you believe you are feeling is an actual boost in T (check T-levels) or hepatic side effects (check ALT, AST & ALP).”(71)
11. Use creatine on a daily basis
Probably everyone who have trained with weights have heard of creatine. It is literally everywhere: in the gyms, in natural stores, supplement sites and even in normal grocery stores. Creatine monohydrate is not a new invention, but rather an old one. The earliest studies on creatine and performance come from the early 1990s.
Creatine is naturally occurring in red meat and in almost all vertebras. It functions in skeletal muscle energy production by increasing the amount of ATP in the cells. The specific energy system is creatine-phosphate or phosphagen system. In the cells creatine phosphate (CP) donates a phosphate to ADP to produce ATP. Creatine phosphate system activates in short and intense bursts of exercise (around 5-8 seconds).
The research behind creatine is MASSIVE. There are nearly 100 peer-reviewed human studies showing that it increases strength, muscle mass and power and affects positively on body composition and sports performance.(72)(73) Quite a few studies have also shown that supplementing with 5 grams of creatine per day increases testosterone and DHT significantly.(74)(75) Especially when beginning with the supplementation the elevation on DHT is especially high.(76) One study showed that creatine also helped to diminish potential harmful effects of short-term overtraining while maintaining higher testosterone levels compared to those who didn’t supplement with creatine.(77)
Longer term usage of creatine has not been shown to have any negative/adverse health effects. An overall trend towards higher testosterone serum levels has been also observed (on average from baseline of 17 nmol/l to 26 nmol/l).(78)
One review done in 2011 concluded that ”…high-dose (>3-5 g/day) creatine supplementation should not be used by individuals with pre-existing renal disease or those with a potential risk for renal dysfunction (diabetes, hypertension, reduced glomerular filtration rate). A pre-supplementation investigation of kidney function might be considered for reasons of safety, but in normal healthy subjects appears unnecessary.”(79)
More Extreme & Lesser-Known Biohacks Fo High Testosterone
We have now covered the basics for optimizing testosterone that you really need to know and do first. Next, I will introduce you methods that have not been really discussed (not at least extensively) and which go into category ”biohack yourself into a T monster”. These methods are also science-based, but in some of the hacks convincing human studies are still to be seen.
1. Electrical (muscle) stimulation
A study done on rat’s gastrocnemius muscle (calf) found out that electrical stimulation induced a rapid increase in the number of androgen receptors in early parts of the stimulation. This again lead to increase in muscle mass by enhancing the muscle sensitivity to androgens.(80)
Another study conducted in humans showed that an electrical stimulation of volunteers’ meridian points (which basically means electro-acupuncture) increased subjects’ concentrations of total testosterone and DHEA-S without affecting LH or FSH (secreted from the pituitary gland).(81)
2. Red light or low-lever laser therapy (on your nuts)
Red light, near infra-red light (NIR) or low-lever laser therapy has been used to treat various conditions from pain and muscle aches to wound healing, skin conditions, osteoarthritis and even depression. These effects are usually local, but near-infrared light has also systemic effects via circulation of blood. You might want to read this super comprehensive article on red light and NIR by a Finnish medical student Vladimir Heiskanen.(82) He has been a key source of information for me regarding the healing effects of red light.
The basis for stimulating testosterone production by shooting red light and near-infra red light especially on your testicles lies on the mechanism how red (or infrared) wavelengths work inside the cell. The key is that they stimulate ATP production in Leydig cells thus increasing the energy available for the cells. This means more testosterone production.
There might be also other mechanisms, which are speculated in ”Red Light Man” site:
”Another potential mechanism involves a separate class of photoreceptive proteins, known as ‘opsin proteins’. The human testes are especially abundant with various of these highly specific photoreceptors including OPN3, which are ‘activated’, much like cytochrome, specifically by wavelengths of light. Stimulation of these testicular proteins by red light induces cellular responses that may ultimately lead to increased testosterone production, amongst other things, although research is still in the preliminary stages regarding these proteins and metabolic pathways. These type of photoreceptive proteins are also found in the eyes and also, interestingly, the brain.”(83)
I haven’t found any human studies on the subject, but according to a few studies done on rats the positive effects on testosterone production are enormous. For example a Korean study found out that low level laser therapy (LLLT) with wavelength of 670nm (which is in border of visible red light and infra-red light) 30 mins per day showed significant increase in serum testosterone by fourth day of the treatment without any harmful tissue penetration.(84) In that study, a wavelength of 808 nm didn’t have any effect on T production. Another study done with rams didn’t show any positive effects on T production with 808 nm wavelength.(85)
Still, that wavelength (800 nm+) might work on humans on the basis of other LLLT studies on different tissues (such as thyroid).
- Overall, red or infrared light from LED source is generally thought to be a safe therapeutic method
- Avoid heating the testicles, since the heat will destroy sperm cells and have a negative effect on the Leydig cells
- Avoid blue light and UV light exposure on testicles (blue light inhibits ATP production in mitochondria)
3. Get cold showers and swims and keep your testicles cool
”In the 1820s, a German farmer named Vincenz Priessnitz started touting a new medical treatment called “hydrotherapy,” which used cold water to cure everything from broken bones to erectile dysfunction. He turned his family’s homestead into a sanitarium, and patients flocked to it in the hope that his cold water cure could help them.
The first hydrotherapy facility opened up in the U.S in 1843, right when the sanitarium craze hit America. By the end of the 19th century, over 200 hydrotherapy/sanitarium resorts existed in the United States the most famous being the Battle Creek Sanitarium founded by John Harvey Kellogg.”(86)
There is no straight-forward evidence that cold therapy would raise testosterone levels. But the indirect evidence exists. One study conducted in 1988 in Finland investigated serum levels of thyroid and adrenal hormones, testosterone, TSH, LH, GH and prolactin in men after a 2-h stay in a cold room (10 degrees Celsius). There were no significant changes in the serum concentration of adrenalin, T3, T4, testosterone, TSH or LH. The serum level of noradrenaline increased from 4.5 to 6.3 nmol L1 (P < 0.01) and those of Cortisol, GH and prolactin fell by 20, 87 and 48% (all P < 0.01). This means that by lowering cortisol you would probably have more of the raw material for testosterone production and less stress response.(87)
The indirect research evidence by in vitro (and animal) studies on optimal testicle function gives us information that the ball sack should be kept cool (under 35 Celsius or 95 Fahrenheit) also for optimal testosterone production.(88) Heat exposure into testicles has been shown to reduce testosterone levels in rats. Also an observational study done on over 6000 men showed that sperm quality and volume were greater in the winter time. This is due to stimulation by FSH and LH secreted from the pituitary gland, which also stimulate testosterone synthesis and secretion.(89)
There are also anecdotes from old school Chinese and Russian powerlifters who iced their balls after training and also before competition. Apparently their goal was to increase performance and testosterone function.
Do these things to improve testicle function:
- Take cold baths and showers with cool shower head
- Wear loose boxers or go ”commando” to keep optimal temperature for testicles and to avoid compression
- Sleep naked or wear just loose pyjamas (no undies)
- Sleep in a relatively cold room temperature
- Don’t sit unless it is absolutely necessary
According to a comprehensive research site Examine.com:
”Boron is a dietary mineral that, although it has a daily intake, has not been accepted as an essential vitamin or mineral. I currently does not have a known minimum requirement.”
Boron is found in small amounts in the earth’s soil. It functions as a fortifier in cell walls, in the bone, in reproductive system as well as in the brain. A Boron deficiency (daily intake less than 0.23 mg per day) alters brainwave activity similar to magnesium deficiency by decreasing frontal lobe activity. A deficiency state has been associated with cognitive impairment.
Best food sources for boron are raisins, dried grapes and peaches, almonds, avocado and dried plums. Boron is well absorbed form the intestines.
One human study showed that boron supplementation (10 mg per day) increased free testosterone (via reduction in SHBG) and DHT levels and decreased estrogen levels. Boron supplementation also seems to lower pro-inflammatory cytokines.(90) One study done on bodybuilders found out that supplementing with 2.5 mg of boron did not have any effect on testosterone levels.(91)
A study done on rats showed that boron accumulates in the testes and thus long-term use will probably produce the best benefits of using boron. The same study also showed, that with toxic boron doses it can actually cause testicular lesions. For humans the safe dosage is up to 20 mg per day (the tolerable upper limit).(92)
Iodine is an essential mineral, which means it must acquired via diet. Iodine is critical in brain and central to the active thyroid hormones (T3 and T4). Severe deficiency in iodine can result in reduced cognition or cretinism. The thyroid gland absorbs iodine from the blood to make thyroid hormones. Approximately 15–20 mg of iodine is concentrated in thyroid tissue and hormones. Still, 70% of the body’s iodine is distributed in other tissues such as mammary glands, eyes, salivary glands and testicles.
Iodine is most abundant in seaweed and seaweed based products such as nori. Daily intake of iodine should be at least 75–150 micrograms per day. For adults an upper intake level is 3000 micrograms.
Lack of iodine in the body (especially in the thyroid gland) can cause various health problems. The most common is hypothyroidism. Men with primary hypothyroidism have subnormal responses to luteinizing hormone (and GnRH) and their free testosterone concentrations are also reduced.(93)
It has been noticed in rats that by increasing iodine supplementation the mean weight of the testes also increased quite a bit. However, the epididymal sperm counts went down a bit.(94)
One possible explanation for the higher occurrence of hypothyroidism and hypogonadism in men today when compared to say like 30 years ago, is an increase of environmental toxic halogens like fluorine, chlorine and bromine. When concentrated enough in the body they will replace iodine’s locations inside the cells (especially in thyroid cells and Leydig’s cells).(95)
It is critical to have enough iodine in your system to also optimize testosterone production. Some people have even taken this further by painting their testicles with Lugol’s iodine (which is highly concentrated potassium iodine). The protocol also includes supporting minerals such as selenium, magnesium, vitamin C, oral iodine, co-factors for ATP (B2 and B3 vitamins) and salt.(96) The anecdote by hundreds of testimonials here is that many people did significantly elevate their testosterone production with possible straight stimulation of the Leydig cells by iodine, which would have then lead into removal of other halogens.
I did experiment this with myself several different occasions and at first, I noticed an increase in libido. But, the effect seemed to eventually fade away. The hypothesis for this therapy seems legit, but unfortunately there hasn’t been done any clinical nor animal studies.
A word of caution: Do not take excess iodine and do not over do this (it will cause pain in the scrotum area because of the sensitivity of the skin). This is a potentially dangerous biohack, so be careful. As a medical doctor, I wouldn’t recommend this to my patients right away.
6. Pulsed electromagnetic fields
The elctromagnetic fields emitted from various sources (e.g. mobile phones, microwave owens, wi-fi’s etc.) have been reported to have causative effects on biological systems such as inflammation, radiation and hyperthermia. All of these can disrupt the seminiferous tubules and reduce the Leydig cell population and testosterone concentration (studies done in rats).
Pulsed electromagnetic field therapy (PEMF therapy) has been used successfully to treat various health conditions ranging from bone healing and pain relief to balancing the neuroendocrine system (including hormone production and melatonin levels).(97)
There is exists a study conducted on male Wister rats, which showed that PEMF therapy helped rats to bounce back from microwave radiation in terms of testosterone production and to combat oxidative stress. In fact, rats’ testosterone levels went a bit higher than before the microwave radiation exposure after they were treated with PEMF for 60 days.(98)
Many men keep their mobile phones in their front pockets quite close to testicles. It is a fact that mobile phones emit microwaves that are harmful to normal tissues when kept very close to the skin. A number of studies have shown relationships between mobile telephone use and reduced sperm count and sperm quality.(99)(100)(101) The negative effects are highly likely to extend also on reducing testosterone levels in men.
My hypothesis is this: if you know that you are being exposed to external microwaves and wi-fi’s and cell phones, a PEMF device (locally on the testis) or a more general device on whole body treatment, is likely to revive testosterone levels.
A translation of this article in Finnish is also coming up.
Olli Sovijärvi, M.D., head author of the Biohacker’s Handbook
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