Where Has All the Testosterone Gone?

Men today are facing an alarming and underreported health crisis: testosterone levels in the U.S. and other industrialized countries are plunging, and have been for the past few decades. And our modern world is accelerating that decline.

Testosterone is an essential male sex hormone that makes a man a man. It is also critical for overall male health and wellness. It supports mood, motivation, drive, a sense of wellbeing, hair growth, bone density, weight management, muscle mass, and healthy aging.

The problem: today’s man has testosterone levels far below those from 50 years ago, and likely much lower than men hundreds of years ago. Analysis of men in the U.S. aged 15-40 from 1999 to 2016 shows a drop of ~25%.

What’s driving this drop? Stress, obesity and toxic foods are part of the problem. But the causes are complex and so are the solutions.

While testosterone naturally declines with age, we are now seeing a generational drop beginning since testosterone has been measurable in the 1960s. Gen Z men and millennials today have, on average, an estimated half the testosterone levels of their fathers and grandfathers.

Internationally, the patterns are the same. Research conducted in Finland, Denmark, and Israel shows ~25% decline in testosterone levels across all age groups, accompanied by an increase in sex hormone binding globulin (SHBG), a protein that binds and deactivates testosterone.

But testosterone isn’t the only measure of male health in decline. Sperm counts are plummeting, and reproductive disorders like erectile dysfunction, impotence, and testicular and prostate cancer are all on the rise.

Processed Foods, Seed Oils, and Chemical Additives

Here’s what the evidence reveals: The modern American diet is loaded with testosterone-sabotaging ingredients. Ultra-processed foods are packed with refined sugars and starches, which spike blood sugar and insulin, leading to fat gain, insulin resistance, and lower testosterone. Many of these foods also contain glyphosate, atrazine, artificial preservatives, and chemical flavorings.

Seed oils like soybean, corn, safflower, canola, and sunflower oils are rich in omega-6 fats, which drive chronic inflammation and oxidative stress. This inflammation disrupts the hormonal signaling needed for testosterone production. Seed oils even damage the testosterone-producing cells in the testes, and interfere with hormonal regulation. Additives and artificial sweeteners like aspartame also reduce testosterone and alter hormone balance.

Altogether, this toxic food environment creates the perfect storm for hormone dysfunction: low testosterone, poor libido, fatigue, excess body fat, and metabolic disease.

Hormone Disruptors in Everyday Life

It’s harder than ever to avoid chemicals that mess with male hormones. Endocrine-disrupting compounds—especially xenoestrogens—are everywhere: in our food, water, personal care items, household cleaners, plastics, and even medications.

Xenoestrogens are man-made compounds that imitate estrogen and interfere with the body’s natural hormonal signaling.

These chemical estrogens can cause early puberty, low testosterone, infertility, erectile dysfunction, male breast enlargement, and increased risk of hormone-related cancers.

You’ll find these hormone-disrupting compounds in:

• Pesticides and herbicides
• Plastics (especially soft plastics like water bottles and food containers)
• Personal care products like shampoo, deodorant, and cologne
• Conventional meat, dairy, and eggs
• Microwaved food in plastic containers
• Processed foods and preservatives

Atrazine

Atrazine is one of the most widely used herbicides in U.S. agriculture — and a potent testosterone killer. Animal studies show that male frogs exposed to trace amounts of atrazine developed female sex organs and were effectively chemically castrated. Studies have shown similar effects in fish and reptiles.

In humans, atrazine exposure has been linked to suppressed testosterone, reduced sperm quality, and altered sexual development. Atrazine is commonly found in conventionally grown corn, grains, beans, and in drinking water – especially near farmland. It also accumulates in meat and dairy from animals fed corn-based feed.

Glyphosate

According to studies, more than 80-90% of Americans are exposed to glyphosate. Glyphosate, the active ingredient in Roundup, is another widely used herbicide with serious hormonal consequences. It interferes with the enzymes needed for testosterone production, damages testicular tissue, and suppresses testosterone secretion.

Research shows that glyphosate also acts as a xenoestrogen – boosting estrogen and increasing cancer risk.

Glyphosate is sprayed on most grains, legumes, and some nuts. It’s been detected in drinking water, tampons, and even clothing.

High Cortisol and Testosterone

Life has become busy and stressful. Jobs, money, family, climate change, rising prices, wars, and more. More people than ever are dealing with unprecedented levels of chronic stress. Stress not only impacts moods, sleep, and immune function, but the high cortisol from stress affects testosterone levels.

According to research from University of Texas at Austin, chronically elevated cortisol levels block testosterone production, decrease sperm count, increase impotence, and lower libido. In addition to the physical response, other side effects of stress like poor sleep, lowered thyroid function, and low energy also contribute to lower testosterone levels.

Obesity and Testosterone Levels

Obesity, insulin resistance, and high blood sugar are some of the biggest health issues facing U.S. men today. According to the CDC, 76% of men aged 25 or older are overweight or obese.

Overweight or obese men are likely candidates for reduced testosterone levels. A substantial body of evidence indicates obesity is one of the leading causes of low testosterone levels in men across all age groups.

Fat cells contain aromatase that converts testosterone into estrogen. Excess estrogen leads to weight gain, increasing aromatase levels and continuing the vicious cycle.

Other things decimating men’s testosterone levels include alcohol, marijuana, pharmaceutical medications, and chronic diseases like diabetes, heart disease, and obesity.

The silent health crisis the average man is struggling with:

He wakes up tired. He’s overloaded with stress — work, bills, relationships, kids. Cortisol climbs, testosterone levels drop.

Then the cravings hit. Junk food and takeout take the edge off, but they’re laced with chemicals that further hijack hormones. Belly fat grows, and so does estrogen.

Even basic routines betray the average man. Soap, shampoo, and laundry detergent are full of hormone-disrupting chemicals. After work, he skips the gym — he’s too drained — and cracks open a beer or two. That temporary relief increases the hormonal crash.

He’s stuck in a vicious cycle of low testosterone, high estrogen, and zero drive. Muscle fades, fat builds, libido disappears, and depression sets in. It’s not just aging — it’s a full-body shutdown.

And it’s happening to millions of men.

How to Fight Back

RFK Jr. is working to reclaim our food system—targeting pesticides, synthetic dyes, chemical additives, seed oils, and the chronic diseases they fuel. But real change also starts with awareness.

Understanding how hidden environmental toxins affect our hormones is essential — for ourselves and future generations. Awareness is the first step toward reclaiming hormonal health.

By reducing our exposure and committing to a cleaner diet, consistent movement, and smarter lifestyle choices, men can reclaim their vitality and protect their future.

Even though the environmental assault on testosterone is real, the tools to fight back are in our hands:

• Ditch processed food and cook with real, whole ingredients. Cut sugars, refined grains, and seed oils.
• Choose grass-fed meat, pastured eggs, and organic dairy — rich in protein, saturated fats, and micronutrients that support testosterone production.
• Reduce exposure to xenoestrogens – avoid plastic, use natural personal care and cleaning products, and buy organic produce when possible.
• Limit alcohol and marijuana.
• Aim for regular, restorative sleep.
• Lift heavy things. Sprint. Move with intensity. Strength training is one of the best ways to boost testosterone naturally.
• Manage stress through movement, cold exposure, sunlight, and real human connection.

The bottom line? You don’t have to accept declining testosterone as your fate. With smarter choices and a renewed commitment to your health, you can reclaim energy, motivation, libido — and the core of what makes you feel like a man.