Men born in 1990 have lower baseline testosterone than men born in 1950 because the modern environment is loaded with endocrine-disrupting chemicals that interfere with hormone signaling at very low levels, and the most effective response isn't adding supplements but reducing your exposure to the plastics, pesticides, and synthetic compounds driving the decline.
Here’s a number that should stop you: men born in 1990 have lower baseline testosterone than men born in 1950—even after you account for age, weight, exercise, and smoking. That’s not a typo. The decline is roughly 1% per year over the last four decades, and it’s been confirmed in multiple studies.
If you’ve been searching for ways to boost your testosterone naturally for fertility, you’ve probably seen the same advice everywhere: lift heavy, sleep more, eat eggs, cut alcohol. Good advice. But it misses the bigger picture. The environment you live in is actively suppressing your hormones, and no supplement can fully fix that.
I spent months digging through the research on this. Here’s what I learned—and why the most powerful change you can make isn’t adding something new. It’s getting rid of the stuff that’s dragging you down.
The 40-Year Experiment We Didn’t Sign Up For
Back in 1992, Danish researcher Niels Skakkebaek published a paper showing sperm counts had dropped nearly 50% between 1938 and 1990. Critics said the data was flawed. So researchers did the work again. A massive 2017 meta-analysis covering 185 studies and over 40,000 men confirmed it: sperm counts dropped more than 50% between 1973 and 2011, and the decline is accelerating.
Testosterone follows the same curve. A 2006 study in the Journal of Clinical Endocrinology & Metabolism found that a 65-year-old in 2004 had higher testosterone than a 35-year-old in the same year when controlling for health factors. That’s not how biology is supposed to work. Your grandfather didn’t sleep better than you or lift more weights. He probably smoked more and ate worse. Yet his endocrine baseline was higher.
Something in the modern world is interfering. The evidence points to a class of chemicals called endocrine disruptors.
What the Research Actually Shows
These chemicals don’t poison you in the traditional sense. They hijack your hormone signaling at extremely low levels—parts per billion. Here are the main offenders:
- Phthalates – Found in soft plastics, food packaging, and anything with “fragrance” on the label. A 2006 study in Environmental Health Perspectives found that higher phthalate levels in men meant lower testosterone and reduced sperm motility. More exposure, worse results.
- BPA and BPS – In hard plastics, can linings, and receipt paper. BPA mimics estrogen. BPS, the “safe” replacement, turns out to be just as bad. A 2010 study in Journal of Andrology linked BPA to lower sperm concentration.
- PFAS (forever chemicals) – Used in non-stick pans, waterproof jackets, and fast-food wrappers. They don’t break down. A 2023 review in Andrology connected PFAS to lower testosterone and poorer semen quality.
- Pesticides – Glyphosate and organophosphates show up consistently in studies linking exposure to reduced fertility. A 2021 mega-review in Human Reproduction Update found the pattern across dozens of studies.
These chemicals are so pervasive that they’ve been found inside human testicles. A 2024 University of New Mexico study examined testicular tissue from 23 men and found microplastics in every single sample. Polyethylene—the plastic in grocery bags and food packaging—was the most common. The concentration was three times higher than in dog testes from the same region.
How Endocrine Disruptors Wreck Your System
Testosterone production is a chain: your brain releases signals that travel to your testes, where Leydig cells convert cholesterol into testosterone through a series of enzymatic steps. Endocrine disruptors can break that chain at multiple points.
Some block the receptor on the Leydig cell so the signal never arrives. Others inhibit the enzyme CYP17A1, which is essential for testosterone synthesis. Still others mimic estrogen so well that your brain reduces the signal, thinking there’s already enough sex hormone in the blood.
The result is a lower ceiling for your natural testosterone production—no matter how much you lift or how well you sleep.
Why Supplements Can’t Outrun a Bad Environment
I’m not against zinc, magnesium, or vitamin D. If you’re deficient, they help. But they can’t fix a system that’s being actively disrupted. Think of it like a leaky bucket. You can pour in more water, but if the hole is growing, you’re fighting a losing battle.
A 2022 study in Antioxidants examined men with high phthalate exposure. Those who took antioxidant supplements saw modest improvements. The authors concluded that reducing exposure should be the primary intervention.
That matches what I’ve seen across dozens of papers: additions help at the margins. Removals change the baseline.
What You Can Actually Do (The Removal Protocol)
You don’t need to move to a cabin in the woods. Small, targeted changes make a real difference.
Start with Water and Food Storage
- Filter your water. Tap water contains trace pesticides, pharmaceuticals, and industrial chemicals. A basic carbon filter removes many of them. Reverse osmosis removes almost everything. If you’re trying to conceive, this is the single most cost-effective change.
- Ditch plastic food storage. Glass and stainless steel don’t leach. Never microwave plastic. Don’t store hot leftovers in plastic containers. Heat dramatically increases chemical migration.
Clean Up Your Personal Care
- Read labels for “fragrance.” That’s where phthalates hide. Shampoo, deodorant, cologne, lotion—they’re all potential sources. Switch to unscented or brands that disclose full ingredients. Your skin absorbs these compounds directly.
Choose Organic for the Worst Offenders
- Focus on the Dirty Dozen. Strawberries, spinach, kale, apples, and grapes consistently test high for pesticides. You don’t need to go fully organic. Swapping just these few items cuts your pesticide load significantly.
Support Your Body’s Elimination Pathways
- Sweat more. Multiple studies have found heavy metals, BPA, and phthalates in human sweat—sometimes at higher concentrations than in blood or urine. Exercise or heat exposure (sauna, steam) helps your body eliminate these compounds. It’s not a magic cure, but it supports a natural process.
- Increase fiber. Fiber binds to bile acids in your gut and helps shuttle estrogenic compounds out through your stool before they can be reabsorbed. Broccoli, Brussels sprouts, flaxseed, oats. A 2019 study in The Journal of Nutrition linked higher fiber intake to lower circulating estrogen in men.
Clean Your Air and Dust
- Vacuum with a HEPA filter. Household dust collects phthalates, PFAS, and flame retardants from furniture, electronics, and carpets. A HEPA vacuum reduces the amount you breathe and ingest.
Where Sauna Fits (Realistically)
Sauna gets overhyped. No credible study shows it boosts testosterone in the long run. In fact, the immediate heat stress temporarily suppresses testicular function. But here’s the connection: sauna supports the removal strategy. Sweating helps excrete some of the chemicals that are suppressing your hormones.
The Finnish sauna study that everyone cites—2,300 men followed for 20 years—found that those who sauna 4 to 7 times per week had a 40% lower risk of dying from cardiovascular disease. That correlation likely involves multiple mechanisms: better blood flow, reduced inflammation, lower chemical burden.
If you use a sauna, keep sessions around 10 to 15 minutes at a comfortable temperature. Hydrate well. Don’t overdo it. And prioritize the environmental changes first. No amount of sweating fixes a system that’s constantly being re-exposed.
What the “Testosterone Boosting” Industry Doesn’t Tell You
There’s a whole market built on selling you the idea that you need to add things to get your hormones back. Test boosters. Herbal stacks. Pills promising to make you feel 20 again. Most produce marginal results at best.
The removal strategy isn’t profitable. Nobody can sell you a glass water bottle and a HEPA vacuum for the markup they charge on a supplement bottle. But the evidence says it’s more foundational.
If you clean up your chemical environment, optimize your sleep, lift heavy, eat enough protein, and manage stress—your hormones will settle into a better range than if you did all the “boosting” while eating food wrapped in plastic and drinking from a polycarbonate bottle.
What We Still Don’t Know
I want to be honest about the limits. Most of the evidence comes from epidemiological studies—higher exposure correlates with worse outcomes. We don’t have long-term trials proving that reducing exposure directly reverses testosterone decline. That kind of study is expensive and hard to run.
We also don’t know the exact threshold for each man. Some people are more sensitive due to genetic differences in how their liver processes these chemicals.
This is emerging science, not settled fact. But the precautionary principle holds: if you can reduce your exposure to compounds that are plausibly harming your hormone health—with minimal cost and effort—it’s worth doing. Especially if you’re trying to conceive.
The Bottom Line
The standard advice still works. Lift heavy. Sleep seven to nine hours. Eat enough protein and healthy fats. Manage stress. Keep body fat in a healthy range. Those are the foundation, and I’m not arguing against them.
But that foundation sits on top of an environment that’s actively working against it for the first time in human history. Your grandfather didn’t have to think about phthalates in his shampoo or microplastics in his testicles. He could focus on the basics and his body handled the rest.
You don’t have that luxury. The environment has changed. To get the same results, you have to address what’s been added.
The removal strategy isn’t a replacement for the fundamentals. It’s the prerequisite. Patch the leaks first. Then pour in the water.
This article is for educational purposes only. If you’re concerned about your testosterone levels or fertility, talk to a healthcare provider who can run proper labs and discuss your individual situation. The science on environmental endocrine disruptors is still developing, and individual responses vary.
Frequently asked questions
what are endocrine disruptors and how do they lower testosterone
Endocrine disruptors are chemicals that hijack hormone signaling at extremely low concentrations. They can block receptors on the cells that produce testosterone, inhibit enzymes essential for its synthesis, or mimic estrogen so effectively that your brain reduces its own hormonal signals. The result is a lower ceiling for natural testosterone production regardless of how well you sleep or train.
which everyday products contain phthalates and BPA
Phthalates are commonly found in soft plastics, food packaging, and products listing 'fragrance' on the label, including shampoo, deodorant, and cologne. BPA and its replacement BPS show up in hard plastics, can linings, and receipt paper. Switching to unscented personal care products and glass or stainless steel food storage are straightforward ways to cut exposure.
does sauna actually raise testosterone
No credible study shows sauna raises testosterone over the long run, and the immediate heat stress can temporarily suppress testicular function. Where sauna fits is in supporting the removal strategy: sweating helps excrete some of the chemicals that suppress hormones. If you use one, keep sessions around 10 to 15 minutes and rehydrate afterward.
can a high fiber diet help with hormone balance in men
Fiber binds to bile acids in the gut and helps move estrogenic compounds out through the stool before they can be reabsorbed. A 2019 study in The Journal of Nutrition linked higher fiber intake to lower circulating estrogen in men. Foods like broccoli, Brussels sprouts, flaxseed, and oats are practical sources to add to your diet.