The Testosterone Decline Story Is Dead
In a Nutshell
Testosterone levels in U.S. men, which had been declining for decades, have now reversed and risen since 2011 even as obesity increased. Population data cannot explain why or diagnose individuals, but the strongest evidence-based levers are consistent high-quality sleep, substantial fat loss if obese, adequate nutrition without extreme restriction, and smart training recovery. Men with persistently low levels plus symptoms should pursue proper morning testing and consider TRT under medical supervision rather than relying on supplements or abstinence rituals.
These notes were generated by AI and may contain inaccuracies.
The honest answer is that we don't actually know why testosterone levels stopped declining and started going back up because obesity rose from roughly 35% to 39% moving exactly the wrong direction to explain higher testosterone. Population level analyses give very little clarity to your specific situation. How do you maximize your own natural testosterone levels? Don't worry about sex and jerking off. If you're doing all that and your test levels are still low, you might want to consider TRT, but the question is how and when.
We've heard for years that our testosterone levels are falling. Recent research says they're rising. The popular story is that modern men have dramatically less testosterone than their fathers or grandfathers did. Depending on the podcast microphone involved, testosterone has supposedly fallen by somewhere between 30 and 50% or approximately one entire real adult Viking per generation.
The headline of test levels are falling did grow from several legitimate secular trend findings rather than from pure internet vapor. There have been also declines in testosterone that could be attributed to other factors that can be corrected for in these analyses. For example, aging. Testosterone tends to decline as an individual man ages. But a secular decline adjusts for that. That means a 40-year-old tested in 2005 has less testosterone than a comparable 40-year-old tested in 1990. Age adjustment attempts to separate the population got older from same-age men now have lower levels, which is a very different claim.
One big study, the Massachusetts Male Aging Study, produced one of the strongest early signals. Researchers in this study analyzed 1,532 men from the Boston area, which gave 2,769 observations across the late 1980s, the 1990s, and even through the early 2000s. What they found is that a substantial population-level decline that was greater than the decline expected from aging alone. That decline actually survived a bunch of other adjustments for several obvious suspects. It corrected for changes in obesity, which is huge, changes in smoking, medication use, and general health. They didn't fully explain the Massachusetts trend. The Massachusetts study decline was much smaller than just raw data, and they explained some. They didn't prove that these factors had zero causal role, but it means the finding could not simply be erased by saying, "Oh, it's just BMI."
A very large Israeli healthcare dataset points in exactly the same direction. Investigators there examined testosterone tests from over 100,000 men between 2006 and 2019 and reported a highly significant age-independent decline across most age groups. The strongest version of the decline claim seems actually credible. Several populations, different age groups, and different periods show lower testosterone in men tested later, even after age and obesity adjustment, which take care of most of the difference, but not all. The effect may in fact be biologically meaningful, and everyone merely got older and fatter is not the complete explanation.
As is often true about the internet, the number of claims as to why our test levels have fallen is enormous. For explaining the overall decline over time, obesity is probably the biggest proven contributor. More body fat lowers total testosterone, while severe obesity also suppresses free testosterone, which is the stuff doing stuff to your body. In a recent NHANES data set, obesity was linked to about 2.7 times the odds of having a testosterone below the minimum cutoff of 300 ng per deciliter. Obesity from 1970 to 2010 or 2020 has massively increased, so this tracks.
Insulin resistance, diabetes, and chronic illness also matter. Impaired fasting glucose raised the odds of low testosterone by about 55%, while diabetes range glucose nearly tripled them. The relationship also runs both ways, since low testosterone may worsen body composition and make metabolic health worse, which lowers testosterone levels, and the cycle continues. All of these, insulin resistance, diabetic outcomes, glucose handling, and testosterone itself are made worse still via obesity. Even without obesity, insulin resistance and other things can interfere with testosterone levels. This is a massive epidemic in the United States for a huge fraction of people.
Diet composition is often proposed. Might have small effect, but no food or food group is the endocrine assassin all by itself. Some small studies find slightly lower testosterone on very low-fat diets, but almost no Americans eat very low-fat diets. While newer analyses, in fact, find very little difference. Soy and related isoflavones do not appear to lower male testosterone. This has been studied to the ground. Cannabis may lower testosterone, especially in extreme use. It's tough to see if it's the cannabis itself or the degradation in sleep quality that cannabis extreme use causes.
Other factors can be in play as well. Pollution, heat, alcohol, stress, depression, and modern work patterns may each play a role in reducing test levels. Some of these affect sperm more clearly than testosterone, and many effects appear small or strongest only at very heavy exposures to these things. None of these are major players to explain the trend. A lot of people have talked about endocrine-disrupting chemicals. That's plausible, but it's not a solved case. Phthalates, BPA, PFAS, and similar compounds can affect reproductive biology, and some are associated with low testosterone, but the human evidence is observational and very messy. So, plastics caused everything is a far too confident of a take, though it could be true in part.
The entertaining suspects for testosterone reduction are mostly weaker or unsubstantiated. Porn, masturbation, ejaculation, tight underwear, hot showers, phones in your pockets, soy burgers, and insufficient lumberjacking have all been accused. Sexual activity can briefly shift hormones, but there's no good evidence that masturbation caused decades of falling testosterone.
Are testosterone levels still falling? A just published study in 2026 analyzed over 10,000 American men across nationally representative NHANES cycles from 2011 to 2016 and from 2021 to 2023. Testosterone deficiency in these analyses was defined as total testosterone below 300 ng/dL. Reported testosterone users were excluded and measurements used CDC standardized LC-MS/MS methods. Across the entire sample, 25.7% tested below 300. That doesn't mean a quarter of the US male population has clinical hypogonadism, which also requires symptoms and repeat morning testing. It does mean that a lot of folks have very low testosterone levels and would probably benefit from testosterone replacement therapy or at least thinking about it. Some folks coast on 300, some folks are miserable on 400.
From the beginning of the data set to the end, roughly from 2011 to 2023, age standardized raw testosterone levels below 300 ng/dL fell from 29.3% to 22.4%. That trend of increasing testosterone levels survived survey waiting, age adjustment, standardized prevalence estimates, and sex hormone binding globulin related sensitivity analysis. During that time, obesity rose from 35.1% to 38.9%. Low testosterone during that time declined, the opposite of what obesity alone would predict. The paper mainly measured the fraction below 300, not population mean testosterone. The bottom of the distribution could improve without every percentile rising equally. A recent rebound does not erase earlier declines. Testosterone could have fallen for decades and then partially recovered. Both findings can be true.
Extreme sedentary time fell from roughly 40% to 36%, which could have provided some upward people are a little bit less inactive. Access to regular health care improved slightly, potentially help identify and treat obesity, diabetes, sleep apnea, and medication-related problems, but those are all true except for the obesity part, because obesity rose from roughly 35% to 39%, moving exactly the wrong direction to explain higher testosterone. Diabetes range fasting glucose barely changed, despite being associated with nearly triple the odds of low testosterone. Smoking declined, but smokers often show higher total testosterone or sex hormone-binding globulin. Obviously, smoking remains spectacularly unhealthy and interferes with muscle growth, too. It also reduces the pumps that you're getting from training, which is really terrible, but it does keep your test levels high on paper. Age can't explain the increase because it survived age standardization.
Unreported testosterone supplementation, steroids, hCG use, clomiphene, or enclomiphene could have inflated the results. Although, excluding values above 1,000 ng/dL barely changed the results, and very few people actually get these treatments. To complicate matters, COVID created a large sampling gap and may have changed who participated, how they lived, and how healthy they were. The honest answer is that we don't actually know why testosterone levels stopped declining and started going back up. The result probably reflects some mixture of real recovery, maybe some health care changes, sampling, hormone use, testing conditions, and assay differences.
Population level analyses give very little clarity to your specific situation. NHANES tested different men in each cycle. It did not follow the same people from 2011 to 2023. Survey weighting improved representation, but cannot perfectly correct for participation, survival, fasting compliance, or unmeasured subgroup changes. Population averages can shift with age, obesity, health, medication use, smoking, alcohol, income, sleep, diet, exercise, and work patterns. Morning versus afternoon testing, meals, sleep loss, illness, dieting, and hard training can all change individual results. Also, the 300 cutoff creates a bit of an artificial cliff. A man at 299 and another one at 301 are basically in the same exact situation, but the cutoff splits them into you're totally fine and you need help. Sexual activity may cause brief hormonal fluctuations, but masturbation frequency is unlikely to explain a national multi-decade trend. And also the reversal of that trend. Endocrine disrupting chemicals may matter, but human studies struggle with chemical mixtures, confounding, exposure measurement, and reverse causality.
We barely know why the average changed. And the average still cannot diagnose you. Symptoms, health, medications, fertility goals, and repeat testing matter far more for your levels.
Before considering all of that, there are massive things you can do to boost your test levels personally. Get consistent high-quality sleep, usually around 7 to 9 hours, and treat serious sleep disorders like apnea ASAP. Lose excess body fat when obesity is present. Substantial weight loss is probably the most reliable, broadly applicable natural intervention to boosting your testosterone. If you're over as a male about 15% body fat, losing fat is very likely to help.
Avoid prolonged, severe dieting or unsustainably low body fat, especially when you're already lean. Eat enough calories, protein, essential fats, fruits, vegetables, and micronutrients to avoid deficiency. Eating a healthy, high-protein diet is a big deal. If you eat too little protein, or you eat too little carbs, or you eat too little fats, or you're eating too few nutritious foods like veggies and fruits, your test levels won't be ideal. Cutting out entire food groups is almost always bad for test levels. Avoid periods of prolonged psychological stress.
If you're training, that's great, but your testosterone levels won't actually change much. It is a myth that lifting hard makes your testosterone levels consistently higher. But, way too much training, too much volume, too much frequency, and accumulating too much duration of hard training without backing off can definitely lower your test levels. So, if you have a week of crap recovery and all else is good, deload, or just take the week off. Don't worry about sex and jerking off. Have whatever healthy amount of sex or masturbation that suits you. Abstinence rituals and most commercial test boosters have little meaningful evidence for actually changing testosterone levels.
When you're testing your test levels correctly, two separate fasting mornings after normal sleep, while healthy and not deep into contest prep, is the way to go. When you have your test levels checked, also check sex hormone binding globulin, free testosterone, ideally also estradiol, when appropriate.
If you're doing all that and your test levels are still low, you might want to consider TRT. You might be a candidate for TRT if your test levels are low. Signs your test might be low include reduced sex drive, fewer morning erections, infertility, hot flashes, testicular shrinkage, body hair loss, anemia, and declining bone density. Other signs can include fatigue, brain fog, low mood, poor sleep, fat gain, and weak gym progress. A lot of these are pretty non-specific and have a bunch of different causes, but if they all occur together and your testosterone levels are low, you know you're on to something. Another one is a lower desire to train. Not a bit lower, like a lot lower. Like you used to be pumped going to the gym and now you're just like, "Uh." And workouts are really tough to get through motivationally.
If you have these signs, especially if you have a lot of them all at the same time, go to your doctor and ask to be examined for your testosterone levels. It's a super cheap test, so you might as well throw in FSH, LH, estrogen, free testosterone, SHBG and them all as well. If that comes back on the lower end and you have a bunch of those symptoms, now that's a conversation about potential TRT to have with your doctor. With your doctor. Don't free will this stuff, guys. It often ends really poorly that way. If your test levels are normal, but the symptoms all match lower testosterone, that's also a conversation. Because what's normal for some is low for others. So you could actually still be a candidate for TRT even if you have relatively normal levels, but you experience all the symptoms.
If and when you get on TRT, every few months, monitoring of values is critical. You're going to want your doctor to help you increase and decrease the amount you're prescribed, so you can see how your measured test levels change and measure health markers, as well as like how are things feeling and how are things doing in the gym. Your ideal test levels are when the values on measurement aren't insanely off the charts, right? They're in a good high average range. Your health markers like blood pressure, cholesterol, liver values, and so on are their best. And your mood, sexual stuff, and lifting are also at their best. It's going to take some time to get there to that ideal range for you, but you can. And then you don't have to worry about who has rising or declining testosterone levels in the population because you will be swimming in gains and in female ejaculate ideally.
Test levels were going down for a while. Yes, they stopped going down. No, we have no idea why, but your own test levels are very much in your own hands. Just like the organs that produce them.
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