Testosterone is falling all around the world. This hormone is critical for health and vitality. In this article you will find out what lowers testosterone.
This article is a work in progress, check back often!
“Endocrine disruptors” and “Xenoestrogens”
All kinds of garbage chemicals float around messing up your hormone system. This site will explore how to block them all and keep yourself healthy and strong!
- Water filters for your drinking and shower water both.
- No plastic shower curtain off-gassing damaging chemical fumes. Get a glass door instead. No problem!
- Organic food with no seed oil in it, note that you can still eat “junk” snacks such as potato chips as long as they’re free of chemicals and seed oils, which makes them not junk anymore!
- Soaps and shampoos without bad chemicals, such as this shampoo/body-wash combo – we’ll post a guide to this soon.
- Cosmetics and lotions – there will be a guide to this too.
- Cookware with no chemical coatings (or exposed aluminum), glass bottles instead of plastic.
- Clothes, bedding, and furniture made with natural fibers and no chemicals. Artificial fibers like polyester may lower testosterone.
- Dishwasher and laundry detergents that won’t damage your health and hormones. The best we are aware of is from Dapple Baby. They make certified glyphosate-free products, from the least chemically weird stuff.
Dishwasher Detergent Pacs by Dapple Baby, 25 Count Pouch
If you want in-depth info on all the things that lower testosterone and what to do about it, then read on!
Agricultural Chemicals like Pesticides
Countries that use a lot of agricultural chemicals seem to have much lower testosterone than those that don’t. The correlation appears pretty strong.
More information here: https://testosteronedecline.com/pesticides-lower-testosterone/
You can prevent a lot of agricultural chemical exposure by
1) Not living or working near “industrial agriculture.”
2) Eating food raised without chemicals.
3) Filtering pesticides out of your water, especially if you live near industrial agriculture. Pesticides seep into the water from farm fields and end up in your body.
What job has the highest testosterone levels?
In the USA, for 2013-2014, here are the average testosterone levels for different occupations, industries, and hours worked. (Job data doesn’t seem to be available for 2015-2016.)
Here’s testosterone for the different occupations, and below is testosterone for the different industries. The average testosterone for all the USA data in 2013-2014 was 462 ng/dl, so you can use that for comparison.
Here’s testosterone for the different industries.
I was wondering about the results from the arts, entertainment, recreation industry so I checked into them. A lot of the datapoints in that group were for those whose occupation was something not particularly related to arts or entertainment, such as transportation or maintenance occupations, despite being in that industry. There were only two datapoints in this industry that also had the “Arts, Design, Entertainment, Sports, Media” occupation, and these two datapoints were 486 and 285, averaging 386. Not so high as that original 505 for the broader industry.
I also looked at the sales occupation in more depth. Several of the industries contained those whose occupation was sales. Here are the testosterone levels of the sales workers in each industry.
- Manufacturing: Non-Durable Goods (two guys) = 598 (avg of 736 and 459)
- Professional, Technical Services (four guys) = 565
- Real Estate, Rental, Leasing (five guys) = 562
- Industry: Other Services (one guy) = 549
- Accommodation, Food Services (one guy) = 531
- Retail Trade = 468
- Finance, Insurance = 381
- Wholesale Trade = 374
- Manufacturing: Durable Good (three guys) = 313 (average of 379, 302, 258)
- Construction (one guy) = 268
- Information (two guys, they were 1290 and 333)
Here’s testosterone levels compared to number of hours worked.
Among those who worked zero hours, those who were under 65 had an average testosterone level of 480. (The average for all under 65 was 473) And among the zero hour workers, excluding those who said they aren’t working because of heath or disability, and excluding those over 65, the average testosterone level is 490. But the zero hour workers (of any age over 18) who said their main reason for not working last week was “Taking care of house or family” were 435 ng/dl testosterone.
Here’s testosterone levels for each type of employer, private, government, self-employed, etc.
Remember, the average of all the USA data (over 18, male) was 462 for 2013-2014.
Does education lower testosterone?
In 2013 – 2014, in the USA, among males over 18:
- College graduates and higher were 445 ng/dl.
- Those who’d only completed “some college” or an associate degree were 446 ng/dl.
- Those who were only high school graduates were 483 ng/dl.
- Those who didn’t have a high school degree but had completed 9-12th grade were 458 ng/dl.
- Those who had only completed something less than 9th grade were 473 ng/dl.
So basically, any kind of college seems to go along with slightly less testosterone, but it’s not a big effect on average, and there were both high and low testosterone datapoints in all the groups.
However, when you include BMI (whether a person is overweight or not), it looks like education may sometimes go along with higher testosterone in those who are not overweight (BMI under 25), as you can see from this chart.
The chart also shows that race/ethnicity is involved too.
More questions I plan to answer in this article soon (this is a draft):
Are smart people higher or lower testosterone?
Do soldiers have higher testosterone?
What about religiosity? (israel, palestine, also i can compare secular students to madrassa students)
Has testosterone always decreased with age? (actually, put that in test 100 years ago)
Same with “has test fallen in the lean and healthy too?”
In the 2015-2016 USA data I didn’t see any noticeable correlation between testosterone and family size.
I saw no serious correlation of testosterone and height across all the data.
Testosterone and BMI, 2015-2016, USA, 18+
Very strong correlation.
- BMI 16-17.5 (only 6 guys): 618 ng/dl (For a 5’10” man, that would be 112-122 lb bodyweight)
- BMI 17.5-18.5: 796 ng/dl (A 5’10” man would be 122-129 lb)
- 18.5-20.5: 623 (5’10 = 129-143 lb)
- 20.5-22.5: 577 (5’10 = 143-157 lb)
- 22.5-24.9: 571 (5’10 = 157-174 lb)
- 25.0-26.5: 472 (5’10 = 174-185 lb)
- 26.5-28.5: 450 (5’10 = 185-199 lb)
- 28.5-29.9: 418 (5’10 = 199-209 lb)
- 30-35: 395 (5’10 = 209-244 lb)
- 35-40: 338 (5’10 = 244-279 lb)
- 40-45: 317 (5’10 = 279-314 lb)
- 45 and over: 283 (5’10 = over 314 lb)
The CDC considers under 18.5 BMI to be underweight, 18.5-24.9 to be normal weight, 25-29.9 to be overweight, and 30+ to be obese. The average testosterone of everyone who was lower than 25 BMI (everyone who wasn’t overweight) was 589 ng/dl.
I was surprised that testosterone kept going up with lower BMI even when the BMI was already low enough, even into the underweight range. Perhaps these guys were hyperthyroid? (that’s linked to high testosterone). Whatever the reason, I don’t advise being underweight or losing weight to get down into the underweight range.
Testosterone and race/ethnicity
In 2015-2016 USA, among all males 18 and over
- Non-Hispanic Asian: 496
- Non-Hispanic Black: 489
- Other Race – Including Multi-Racial: 481
- Mexican American: 449
- Non-Hispanic White: 446
- Other Hispanic: 424
Among all non-overweight (under 25 BMI) males 18 and over, however, average testosterone was 589 ng/dl, and among these non-overweight males:
- Non-Hispanic Black: 678
- Other Race – Including Multi-Racial: 642
- Mexican American: 584
- Non-Hispanic White: 578
- Non-Hispanic Asian: 545
- Other Hispanic: 511
Controlling for education levels, things are interesting:
Controlling for prescription meds:
???
Testosterone and age, 2015-2016
Everybody (all BMI)
- 20-24: 535
- 25-29: 556
- 30-34: 461
- 35-39: 466
- 40-44: 465
- 45-49: 430
- 50-54: 480
- 55-59: 441
- 60-64: 433
- 65-69: 454
- 70-74: 375
- 75-80: 388
What I notice here is that Americans currently have a big drop off in testosterone after 30. It’s interesting that I see no such drop off in a lot of data from the past. I think this suggests that something in the American environment now is lowering testosterone and that after 30, the body has lost some of its ability to fight against whatever this is.
Everybody with under 25 BMI (normal BMI)
- 20-24: 681
- 25-29: 668
- 30-34: 584
- 35-39: 621
- 40-44: 677
- 45-49: 570
- 50-54: 679
- 55-59: 584
- 60-64: 529
- 65-69: 480
- 70-74: 488
- 75-80: 464
Again, the average testosterone of all those with BMI under 25 was 589 ng/dl.
Testosterone and household income
In the 2015-2016 USA data I saw no noticeable correlation between testosterone and household income either. Perhaps the levels over 55k were a bit lower than under 55k but it’s not clear.
100k+ = 446
75-100k = 461
65k-75k = 436
55-65k = 409
45-55k = 470
35-45k = 454
25-35k = 488
20-25k = 455
15-20k = 450
10-15k = 477
5-10k = 467
0-5k = 446
Code 0 = 547 (average age of that was 43, so not particularly skewed by too many young guys)
wait so what is code zero
Is testosterone higher in the city or in the country?
Hunter Gatherers and other tribal groups
Testosterone is higher in traditional tribal groups than in the same tribal groups settled.
Turkana nomadic pastoralists: 943 (mean age 45.4)
Turkana settled agriculture: 675 (mean age 43.5)
Bundi hunter-gatherers: 950 (age: early 20’s)
Bundi urban: 686 (age: early 20’s)
Average of four South American hunter-gatherer tribes (Surui, Xikrin, Paracana 1 &2): 749 (full age range I think)
South American tribe (Paracategê ) with a somewhat more modernized life (lived near the highway, got supplies from supermarkets): 608 (full age range I think)
(more info, with sources, here)
South Africa, from the most rural to the fully westernized suburban
South Africa 1981 – age 60-73: Ethnic Africans living in “a rural area of the Transkei” – eating traditional diet – 606 ng/dl. Dropped to 472 after three weeks living in a hotel eating the Western diet. (source)
But then, also in South Africa, age 20-82, from 1996-1998, adjusted for age and BMI by the study, and excluding those taking medications and those with known diseases:
- Living in tribal areas/ “rural village” – 525 (original raw data was 493 at age 45.8)
- Living (working) on commercial farms / “farm workers” – 460 (original raw data was 486 at 36.1)
- “Squatter camps” or “informal settlements” – 435 (original raw was 467 at 31.8)
- “Living in established townships w/ full access to water & electricity” / “urban townships” – 530 (original raw was 524 at 40.4)
- “Fully westernized subjects living in western-type houses in upper class suburbs” / “urban affluent” – 595 (original raw was 623 at 33.2)
(Ethnicity was not specified.)
(source)
However, another datapoint from 2003, “rural-dwelling southern African subjects of predominantly Swazi and Shangaan extraction” are the highest of all though. 808 in non iron poisoned, at mean age 52. (lower in those iron-poisoned) (source)
So South Africa looks like a U-shaped curve, testosterone is high in the very rural tribal (as long as they aren’t diseased or poisoned by some lifestyle factor or have parasites), and it is high in the upper class, fully westernized people. But testosterone is low in the favela type situation.
(The stuff below is a draft for future writing.)
Nigeria urbanization
I can get some stuff from modern Nigeria too. It looks like urbanization is lowering them.
Iran, urban vs rural
Urban near Arak, Iran – 612 ng/dl, Rural near Arak, Iran – 661 ng/dl. (source)
Iran, urban vs rural. (I have several really, Amirkola?)
Finland
Finland old rural
USA
US modern pesticide midwest, but note that my big city results are consistently low. Discuss how midwest went from higher to lower:
US farmers – black NC, and also from current NHANES.
Boston vs suburbs: (include Belmont from the past)
Pennsylvania – I can compare PSU, Hershey, Pittsburgh. Also I have Danville but don’t know the age (it’s prostate stuff so probably older) – although be aware it may not actually be Danville, that may be false info.
I’m able to compare some San Fran and LA neighborhoods.
I have Minnesota foresters I could compare to Rochester, MN. And also broader Olmsted county, but I don’t know about that one.
Mexico
In Mexico, from October 2019 to February 2020, using salivary testosterone which is less reliable and we won’t try to compare it to blood testosterone results. All these guys were university students or workers.
Suburban: ~2.61 pg/ml (age 34, BMI 27.4)
Urban: ~2.76 pg/ml (age 24.7, BMI 24.2)
The suburban are a bit older and a good deal fatter than the urban sample, both of which will bring testosterone down, especially the difference in overweight-ness. To be honest, this probably accounts for the testosterone difference.
(source)
and i have some more mexico too
From a database
Surely I can find one of those databases to show urban vs rural, maybe a European one.
Brazil, Egypt, Thailand
I have for Brazil and for Egypt and maybe for Mexico and for Thailand, but it’s all pesticides, data from rural areas vs cities.
China
In March-May 1982, farmers from rural areas near Chengdu, China, were 718 ng/dl at a mean age of 46.3. (source) But in Shanghai (a big city) from January 1982 to June 1983, age 26-72, testosterone was 532 ng/dl. (source)
Britain
London is consistently lower, and I have one from High Wycombe but don’t know age.
Canada
I have one from Ontaria suburbs, but I don’t have anything to compare it to.
Turkey
Turkey probably has some
Sweden
Sweden probably has some
Calorie deficit
One study looked at a bodybuilder doing an intense fat loss diet. During his 6 month diet, the bodybuilder’s testosterone dropped from 922 ng/dl to 225 ng/dl over the first three months, and remained in the low 200’s after the next three months as he continued to diet to get even leaner. When he stopped dieting, and began eating plenty of food again, his testosterone came back up.
Maybe not all diets will drop testosterone this drastically, but dieting certainly does tend to lower testosterone. Not good!
Low carbs
That low carb diet might be ruining your testosterone levels. (Source) It seems that the body wants plenty of food energy before it is willing to raise testosterone.
Without sufficient carbs, the body seems to consider itself to be in a starvation situation, as mentioned in this paper by Kyle Mamounis. https://www.researchgate.net/publication/315135313_The_Dangers_of_Fat_Metabolism_and_PUFA_Why_You_Don%27t_Want_to_be_a_Fat_Burner
Not only does this carb-starved situation probably signal to the body that it can’t “afford” to produce testosterone, but low-carb also (initially) causes a corresponding rise in cortisol, which is a stress hormone that generally lowers testosterone.
So it’s not surprising to find that there’s a correlation between low testosterone and a high protein but low carb diet, which is the typical Paleo style diet with not a lot of carbs but plenty of meat and fish. Excessively high protein seems to lower testosterone too, which I will discuss further down.
PUFA
(Source)
PUFA is the type of fat found in seed oil like canola oil or soybean oil, the industrially produced fats used for making most processed foods. PUFA is also the type of fat found in Omega 3 supplements, which you may have been advised to consume by health gurus. You can read more about the possible dangers of Omega 3’s here: https://fishybusiness.site/
Saturated fat is the major component of coconut oil and of animal product fat, like butter.
Studies suggest that countries that consume a lot of PUFA have low testosterone compared to low PUFA countries. (And this includes Omega 3’s, not just Omega 6’s.)
More info here: https://testosteronedecline.com/pufa-lowers-testosterone/
The worst kind of PUFA is the PUFA found in vegetable oils, also known as seed oils. You can see that testosterone in America has dropped alongside the rise of seed oils.
Lowering testosterone isn’t the only bad effect of seed oils. Seed oils are involved with cancer, heart disease, obesity, and pretty much all the degenerative conditions that we struggle with today! To learn more about avoiding seed oils, you can check out https://noseedoil.com/
You don’t have to give up snacks to avoid seed oil. You might be interested in our potato chips fried in tallow, not seed oil, available at https://noseedoil.com/chips
Physical Trauma (disease, surgery, infection, wounds, immediately after TBI)
Any acute trauma will drop testosterone very low and very fast. Testosterone levels seem to recover over about a week’s time. Traumatic Brain Injury, such as a concussion, has this short term effect, but also there is often lasting damage done to the brain, and testosterone does not rise all the way back up, even a year later. I wrote more about that below.
Intense physical stress
Ranger School, an intense military training school involving fasting, cold exposure, sleep deprivation, and intense exercise is an 8 week event that absolutely crashes testosterone. Testosterone drops from 499 ng/dl to 87 ng/dl, which is extremely low, and totally insufficient for male function. After Ranger School is over though, testosterone rises back up. (Source)
This illustrates why “hardcore” practices are likely to lower testosterone rather than raise it, contrary to what people often assume. Not many people are putting themselves through something as intense as Ranger School, but there are some that are taking cold showers, training very hard in the gym, fasting frequently, and maybe burning the candle at both ends to get more work done, and these people should know that this is probably dropping their testosterone considerably.
Since these things are often done under the impression that they are RAISING testosterone, this is a very important concept to know! Hardcore stress on the body tends to damage it. By itself, stress does not make you “stronger.”
Very often, to become stronger, we need to relax and have some leisure. Of course this is not a license to eat junk food and scroll social media all day. That will weaken you too.
Fasting
(Source)
Fasting lowered testosterone from 556 ng/dl to 391 ng/dl over an 83 hr fast. (about 3 and a half days without food)
Feeling Defeated
Animal studies suggest that if you accept defeat you will have lower testosterone. Keep your chin up, don’t give in!
Darkness
Researchers found out that bright light increases testosterone. Depressed men had testosterone of 210 ng/dl, until they were exposed to a bright light box daily for 30 minutes soon after waking up. After two weeks of this, their testosterone rose to 360 ng/dl, which is a 71% increase, pretty impressive! They probably felt much, much better going from very low and insufficient testosterone up to 360 ng/dl, which is sufficient for at least a low level of male function.
Preferably you would get this bright light from going outside or sitting at a window, but if this is not possible for you, you can get a light box. The fluorescent light in the typical office is not really bright enough, believe it or not. In an office environment you ought to have a light box, or a lamp, or something to make it brighter where you are.
This light box has the same 10,000 lux brightness rating as the one used in the study:
Verilux HappyLight Luxe – UV-Free LED Therapy Lamp, Bright White Light with 10,000 Lux
I have one like this and I like it a lot. I usually feel better when I use it.
Bad sleep
Consistent sleep loss has been seen to lower testosterone quite a bit. One study suggests that late bedtimes are worse for testosterone than early waking is.
TBI long term effects
Testosterone was measured following traumatic brain injury. Testosterone drops very far right after TBI, but then it partially recovers. Unfortunately it often does not fully recover. Possibly this is because the parts of the nervous system that regulate testosterone production have been damaged.
One severe TBI could do the damage, or several more mild TBI’s. However, even just one mild TBI could do it sometimes.
It is probably wise to avoid hard sparring in boxing, and the causes of traffic accidents.
Sadly, veterans often have TBI’s from the blast wave of nearby explosions.
There are other sources of brain injury than TBI, such as infection, and the long term effects of long-lasting depression, actually.
I believe that extreme “headbanging” can either cause or exacerbate TBI over the long term.
Brain injuries can be somewhat healed over time. Supplying the brain with energy by eating plenty of carbs, and reducing inappropriate inflammation by avoiding excess iron, alcohol, and PUFA are all good ideas. Lots of deep sleep is valuable.
“Red light” exposure on the head and pregnenolone could help facilitate brain healing. Pregnenolone is a precursor hormone which is found to increase the levels of allopregnanolone in the brain, a neuroprotective substance that helps the brain heal, and which is being studied as a way to reverse depression.
Psychological Stress
Distress is not good for your hormones!
“Psychological stress suppresses levels of circulating plasma testosterone.”
Low fat
Does a low fat diet = Low testosterone body? This study thinks so.
Excess protein
Apparently too much protein is correlated with low testosterone. I’m not sure why. Here are some studies related to this:
Testosterone and cortisol in relationship to dietary nutrients
Deficient Zinc
A zinc deficiency is associated with lower testosterone.
Deficient Copper (but don’t be excessive either)
Supplementing high levels of zinc without a corresponding amount of copper will deplete your body’s copper supply, which has been seen to cause low testosterone. Supplements which contain a bit of copper as well as zinc are therefore better than those that contain only zinc. However, it is important to not consume excessive copper either, because this is harmful.
Excess Iron
Watch out for food products with excessive added iron!
Overtraining (weights or aerobic)
Excessive demands on your body seem to cause low testosterone. This is called “Exercise Hypogonadal Male Condition.” Many people lift weights to increase testosterone, but there is a serious risk of going too hard and actually lowering testosterone. It may actually be the norm among serious lifters. It is probably for this reason that one study found elite powerlifters have quite low testosterone. Runners and other endurance athletes frequently have lowered testosterone as well.
Alcohol
Health books and websites rarely mention it, but alcohol is quite bad for you. It seems that it probably lowers testosterone. One study from Gangtok, India found much lower testosterone in alcoholics than other people. Normal men had 756 ng/dl testosterone, while alcoholics had 496 ng/dl. This is a 34% decrease.
RF Exposure and possibly EMF exposure (phones, electric razors, laptops, offices, cities)
One study exposed rats to a cell phone making a call for an hour daily for three months. The rats’ testosterone dropped 51% from 634 ng/dl to 310 ng/dl. (Source) I’m not clear right now how this applies to humans, but it’s concerning.
Another study had similar results.
I strongly suggest turning off your cell phone, and turning off wifi in your house and using ethernet cables instead. The strongest sources of RF exposure in a typical person’s life are probably the cell phone in your pocket and the computer in front of you. My phone was constantly transmitting, and transmitting powerfully too. You can carry your phone turned off and you will be exposed to far, far less RF and EMF. Putting it on airplane mode will greatly diminish the RF, but not the EMF, which is certainly a huge improvement, and if you’re not willing to turn off your phone you can do that instead. Some people say that turning your phone off isn’t enough, but as far as I’ve seen, my phone basically stops transmitting detectable RF and EMF when it’s off.
Next, connect your computer to your router with ethernet cable so that you can turn your computer’s WiFi off (this is the important part). The router itself is not that powerful when you’re pretty far away from it, although I still suggest turning it off. It’s your computer that you sit next to that is really transmitting the powerful waves that could harm you, because you are so close to it.
If you have any other wireless devices, like wireless headphones, or any smart devices, I would really suggest turning them off and not using them. Cordless phones probably transmit RF, likely from the “base station.” I found that the base station was constantly transmitting, all day and all night. I put the base station far away from the part of the house that I spend time in, and that seems to have brought the RF exposure way down, which I’m fine with, since it’s basically impossible to cut RF exposure down to nothing unless you intend to live inside a Faraday cage, or somewhere very remote!
The radio waves from cell towers are far less powerful than the radio waves from the devices right near you.
I haven’t investigated it in depth, but as far as I can tell, EMF from power lines is not really a concern.
If you want to check RF and EMF for yourself, you can get the TriField TF2 detector, which seems to work really well, and I’ve really enjoyed using.
Mold
Disturbingly, some food is contaminated with substances called mycotoxins produced by mold. Mycotoxins seem to lower testosterone quite a bit.
Updates on the Effect of Mycotoxins on Male Reproductive Efficiency in Mammals
It seems that grains are one of the big culprits for mycotoxins, either eaten directly, or when fed to an animal which is then used for meat or milk. Spices, nuts, beer, and wine can also be contaminated. Moldy fruits and vegetables should never be eaten. It may be that people respond well to grain-free diets because of the reduction in mycotoxin exposure. It may also be a benefit of pasture-raised meat and dairy that these animals are exposed to less mycotoxins than grain-fed animals. Mycotoxin contamination is a serious problem in animal feed.
Another source of mycotoxins is contaminated herbal supplements. Mycotoxins can also be produced in moldy buildings.
I don’t currently know how much of an impact mycotoxins have in a normal person’s diet, but it may be a factor to keep in mind.
Cold
Being cold is not good for your testosterone. A brisk cold shower might be a fine idea if it’s quick, but long term cold exposure is definitely not a good thing.
Pituitary-gonadal response to extreme cold exposure in healthy men
Indoor Chlorinated Pools
One study found that testosterone was lower in teenagers who had spent lots of time in indoor chlorine pools as young children. Outdoor pools were fine however.
Noise
Constant exposure to noise is not only aggravating, it actually lowers testosterone too! (Source)
Pollution
Various types of plastic and other pollutants have some testosterone-lowering abilities. I suspect that agricultural chemicals and maybe plastics are the worst though. “Classic” pollution from factories and mines and such may not have too great an effect on testosterone. Russian industrial areas generally have high testosterone. These are probably highly polluted places. The Soviet Union is said to have paid no attention to pollution controls, so the people in these regions have probably been exposed to industrial pollution for a long while, and yet their testosterone is much higher than testosterone in the USA, which has controlled industrial pollution. Strangely, testosterone was higher in the USA in the past, when there was probably more industrial pollution. That does not mean that pollution raises testosterone, but it does suggest that pollution from industry is not the main factor causing the huge testosterone decline in much of the world since approximately 1980. More supporting data: Mechanics in Nigeria, exposed to large amounts of pollutants, have very high testosterone. But of course, some polluted areas do have low testosterone. China has pretty low testosterone in its young people today, and it is apparently quite polluted. But there may be other reasons for this.
Nuclear Radiation from Testing
Kazakhstan has very low testosterone and a very high rate of urological issues, which is strange since much of the rest of central Asia has high testosterone. Maybe it is because the Soviet Union used northeast Kazakhstan for testing many nukes over the years.
Similarly Belarus and Ukraine appear to have quite low testosterone. These are the countries that are closest to the Chernobyl accident of 1986. I have data from some of these areas from before 1986 and testosterone is high!
Japan’s testosterone is also pretty low. Maybe this is the long term effect of radiation from Hiroshima and Nagasaki?
Unfortunately I don’t have testosterone data from Nevada where the USA tested many nukes.
None of this is proof that relatively low level nuclear radiation exposure causes low testosterone, but it is an interesting theory to be considered.
Apparently, just about everyone in the world has been exposed to low but measurable amounts of nuclear radiation from nuclear testing over the last few generations. Maybe this also contributes to the strange decline in testosterone around the world.
Polyester clothes
It’s conceivable that polyester underwear may decrease testosterone production, according to this study. I haven’t investigated it further.
Headphones and music
Strangely enough, listening to music appears to lower testosterone. I don’t know if the effect is really significant or not. I doubt it matters if you listen to a moderate amount of music. But the effect might become significant if you listen to music all day, like many do. I don’t know whether this produces a consistently lowered testosterone or not.
I also suspect that the EMF from headphones might disrupt the brain, which among other things could lower testosterone. I can’t prove this hypothesis right now.
Either way, I believe I have felt better avoiding constantly listening to music, on my headphones.