The Low Testosterone Epidemic: How Declining Saturated Fats from Animal Sources Are Affecting Health

Testosterone is often associated with vitality, strength, and reproductive health—not just in men but also in women. While men typically have higher levels, testosterone plays a crucial role in both sexes, influencing muscle mass, energy, mood, and libido. Yet, testosterone levels are declining at an alarming rate globally, raising serious concerns about fertility, physical well-being, and overall quality of life.

What’s driving this troubling trend?

One significant factor is the widespread reduction in saturated fats from animal sources in modern diets. These fats are essential for testosterone production and maintaining balanced hormonal health. Without them, the body struggles to sustain optimal testosterone levels, setting off a cascade of effects that can negatively impact energy, mood, and reproductive health in both men and women.

Testosterone for Male & Female Health: The Basics

Testosterone, a steroid hormone produced primarily in the testes in men and in smaller amounts by the ovaries and adrenal glands in women, is vital for health in both sexes. In men, it supports reproductive functions like sperm development and libido while contributing to muscle growth, bone density, and overall physical strength through enhanced protein synthesis.

Testosterone contributes to muscle tone, bone strength, steady energy levels, and libido in women, even though they produce it in smaller amounts than men. This hormone also plays a part in regulating mood, sharpening cognitive focus, and supporting metabolic health. In both men and women, testosterone is deeply connected to physical, mental, and reproductive well-being. A healthy balance of testosterone can enhance overall vitality and quality of life.[1]

Testosterone levels also influence mental well-being. Healthy testosterone levels help with mood regulation and cognitive clarity, helping you stay focused and resilient under stress. People with healthy testosterone levels tend to have more energy, thanks to its role in optimizing metabolism, leaving men feeling like they can accomplish more throughout the day. The body’s ability to produce adequate testosterone hinges on a delicate balance of nutrients and hormonal signals, many of which are abundantly supplied by saturated fats in animal-based foods.[2]

Saturated fat plays a vital role in producing healthy testosterone by providing the raw materials the body needs to create this critical hormone. Cholesterol, a saturated fat component, serves as the precursor for testosterone synthesis, making it an essential part of hormonal health. Diets rich in saturated fats from animal sources support the endocrine system, ensuring proper signaling and hormone production, which are key to maintaining healthy testosterone levels and overall well-being.

The Nutritional Foundations of Testosterone

Producing testosterone is a biochemically complex process requiring specific nutrients, many of which are abundant in meat, eggs, and organ meats. These (meat-based) vitamins and minerals help with hormone synthesis and overall reproductive health:

1. Zinc: High in red meat and shellfish, zinc is essential for testosterone production. Zinc is a cofactor in many enzymatic processes in the body. Zinc shields sperm from oxidative damage and supports strong hormone synthesis.[3]

2. Selenium: Found abundantly in organ meats and seafood, selenium is another key nutrient that supports reproductive health and hormone balance. It is critical for maintaining healthy sperm motility and directly supports testosterone production. It also protects cells from oxidative damage.[4]

3. Vitamin D: Found in fatty fish, egg yolks, and liver, vitamin D functions as a steroid hormone precursor. Vitamin D directly influences the pathways responsible for testosterone synthesis, and deficiencies in this vitamin are strongly linked to lower testosterone levels.[5]

4. Cholesterol: As the backbone of all steroid hormones, cholesterol is indispensable for testosterone production. Diets low in cholesterol can hinder the body’s ability to produce sufficient amounts of this hormone, leading to imbalances.[6]

5. Omega-3 Fatty Acids: In fatty fish like salmon and sardines, omega-3s help reduce inflammation and promote cellular health. They help maintain hormonal balance and optimize testosterone levels.[7]

6. B Vitamins: Particularly B6 and B12, found in chicken, beef, pork, and liver, these vitamins support energy production and hormonal regulation. They are crucial for the proper functioning of the endocrine system.[8]

The Shift Away from Animal-Based Foods

Over the past several decades, dietary guidelines and cultural shifts have demonized animal fats and promoted plant-based diets. Though initially aimed at improving cardiovascular health (even though we know now that quality meat is good for heart health), this shift has had unintended consequences for hormonal health, particularly in men.[9] 

Animal-based foods, once a staple of traditional diets, are now often replaced by highly processed plant-based alternatives that lack critical nutrients. According to Dr. Shanna Swan’s groundbreaking book Countdown, declining testosterone levels have coincided with plummeting fertility rates and significant reproductive health concerns, including smaller anogenital distances (AGD) in males—a marker of compromised development.[10]

Insights from Dr. Shanna Swan

Dr. Shanna Swan, a renowned expert in reproductive epidemiology, has brought attention to concerning trends in male reproductive health:[11[[12][13]

1. Falling Testosterone Levels: Studies spanning decades reveal a steady drop in average testosterone levels over the last 40 years. Today, men have much lower testosterone levels than their grandfathers at the same age, highlighting a significant shift in hormonal health.

2. Reduced Sperm Counts: Research led by Dr. Swan shows a more than 50% decline in sperm counts among men in Western countries since the 1970s. This dramatic drop points to serious issues with reproductive health.

3. Smaller Anogenital Distances (AGD): AGD, the distance between the anus and the base of the penis, is a recognized marker of male reproductive health and has also shown concerning changes.

Dr. Swan’s findings suggest that exposure to endocrine-disrupting chemicals (EDCs) and poor nutrition are major contributors to reduced AGD, linked to lower fertility and testosterone levels.

Why Meat Matters for Testosterone

1. High Bioavailability of Nutrients: Animal-based foods provide nutrients in their most bioavailable forms, meaning the body can absorb and utilize them more effectively than plant-based equivalents. For example, the heme iron in red meat is absorbed far more easily than non-heme iron from plants. This makes it easier for the body to get the nutrients it needs to maintain healthy testosterone levels.[14]

2. Complete Proteins: Proteins from animal sources contain all the essential amino acids, making them the best option for building muscle and supporting the enzymes needed for testosterone production. Plant-based proteins often lack key amino acids, which can leave nutritional gaps that animal proteins naturally fill.[15]

3. Cholesterol and Saturated Fat: Cholesterol is the foundation of testosterone production, making it critical for hormonal health. Diets low in cholesterol and saturated fat, often promoted as “heart-healthy,” can actually lower testosterone levels and throw off the body’s hormonal balance.[16]

Animal fats provide the cholesterol needed for optimal hormone synthesis and fat-soluble vitamins supporting reproductive health.

Why It’s Becoming an Epidemic

1. Global Dietary Shifts

Over the last few decades, people have been eating less red meat and turning to processed plant-based foods instead. These options are often promoted as healthier and appeal (due to propaganda) to those trying to improve heart health or make environmentally conscious choices. Unfortunately, many of these products don’t supply the key nutrients the body needs for proper hormone production, like zinc, selenium, and vitamin B12. Swapping out nutrient-rich animal foods for less nourishing alternatives has created a significant gap in the modern diet, taking a toll on men’s health in several ways.[17][18]

Sedentary Lifestyles

Many people spend hours sitting with very little physical activity, especially strength training. This lack of movement takes a toll on testosterone levels, making it harder for the body to stay balanced. Resistance training, in particular, plays a crucial role in naturally boosting testosterone by stimulating the release of luteinizing hormone (LH), which tells the testes to ramp up testosterone production. 

Testosterone levels can take a significant hit without regular physical activity, especially strength-based exercises.[19] When people stop lifting weights, the body’s demand for protein, zinc, and other nutrients needed for testosterone production drops. At the same time, the increasing reliance on convenience foods, which lack the nutrients necessary for muscle recovery and growth, has made the problem even worse.

Without regular exercise and proper nourishment from animal-based diets, both your hormones and muscles can take a hit, leading to lower testosterone levels.[20]

Exposure to Toxins

These days, it’s almost impossible to avoid endocrine-disrupting chemicals (EDCs). They’ve made their way into everyday life, showing up in food packaging, personal care items, and countless household products. These toxins interfere with hormone production and can significantly impact testosterone levels over time.[21]

Plastics containing bisphenol A (BPA), pesticides, and phthalates mimic estrogen in the body, throwing off the delicate balance of male hormones. These toxins can interfere with testosterone production by disrupting the hypothalamic-pituitary-gonadal (HPG) axis, the hormonal pathway responsible for regulating testosterone levels.[22]

Compounding this issue is that many modern agricultural practices rely on chemical fertilizers and pesticides, which introduce additional hormone-disrupting toxins into the food chain. While dietary choices play a role in testosterone health, minimizing exposure to these chemicals through conscious consumer habits is equally critical to counteracting their detrimental effects.[23]

We really don’t realize how much diet and lifestyle can impact our hormones. Without this awareness, they’re unlikely to look for solutions or make changes that could improve their health. If more men understood how animal-based nutrients support testosterone, the growing issue of low testosterone could start to be addressed.

Steps to Reclaim Testosterone Health

Reintroduce Nutrient-Dense Animal Foods: 

You can support healthy testosterone levels by focusing on nutrient-rich animal foods. Grass-fed beef, pasture-raised poultry, and wild-caught fish are great options and are full of the essential nutrients your body relies on to produce hormones effectively.[24]

Organ meats like liver, heart, and kidney should be incorporated into the diet, as they are exceptionally rich in vitamin A, zinc, selenium, and other compounds that directly support testosterone synthesis. Incorporate animal fats like tallow, lard, and butter to supply the cholesterol essential for hormone production. Choosing these nutrient-dense options helps provide the building blocks needed for healthy testosterone levels.[25][26]

Minimize Endocrine Disruptors:

Lowering exposure to chemicals that disrupt hormone balance is key to supporting testosterone production. Use glass or stainless steel containers for food storage, and steer clear of canned goods with BPA-lined interiors.[27]

Choose organic produce whenever possible to minimize exposure to pesticide residues. Transition to non-toxic personal care products and household cleaners free of phthalates and other harmful chemicals. By consciously eliminating these toxins, men can create an environment that supports healthy hormonal function.[28];29]

Strengthen Lifestyle Habits: 

Lifestyle changes can significantly impact testosterone production. Regular resistance training and high-intensity interval training (HIIT) play a key role in stimulating luteinizing hormone production and naturally boosting testosterone levels. Prioritizing quality sleep is just as important, as poor rest raises cortisol, which can interfere with testosterone production. Get 7–9 hours of good sleep each night and use simple stress-management techniques like deep breathing or meditation to keep hormones in balance. Spending time outside is another great way to naturally boost vitamin D levels, which can help support testosterone. Combined with a diet rich in nutrients, these habits provide a strong foundation for healthy hormone levels.[30][31][32]

Educate and Advocate:

Helping men understand the connection between nutrients from animal foods and hormonal health is an important step in addressing low testosterone. Challenging outdated ideas about saturated fat and cholesterol can pave the way for smarter choices and noticeable improvements in overall health.. Changing how we talk about this issue gives men the tools they need to take charge of their health and make meaningful progress.

Regenerative farming practices not only ensures access to nutrient-dense foods but also addresses environmental challenges. Encouraging open conversations about male fertility and hormonal health helps break down stigma and empowers men to take charge of their well-being. By raising awareness and focusing on practical, evidence-based solutions, society can push back against the troubling decline in male hormonal health.

Conclusion

Low testosterone is a growing issue, driven by shifts in diet, exposure to toxins, and changing cultural norms. Restoring healthy levels begins with focusing on the nutrients in animal-based foods, limiting exposure to harmful substances, and making simple, healthier choices every day. Dr. Shanna Swan’s research highlights just how important it is to act now, showing that even small changes can make a big difference for men’s health and fertility. The problem is significant, but practical solutions are well within reach with a thoughtful, informed approach.

Citations:

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11. Swan, Shanna H., and Stacey Colino. Count Down: How Our Modern World Is Threatening Sperm Counts, Altering Male and Female Reproductive Development, and Imperiling the Future of the Human Race. Scribner, 2021.

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19. Kraemer, William J., et al. "Influence of Resistance Training and Protein Supplementation on Hormonal Responses in Well-Trained Men." Journal of Applied Physiology, vol. 96, no. 2, 2004, pp. 530–539, https://journals.physiology.org/doi/full/10.1152/japplphysiol.00656.2003.

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22. Rochester, Johanna R. "Bisphenol A and Phthalates as Endocrine Disruptors: Estrogenic Activity and Impact on the Hypothalamic-Pituitary-Gonadal Axis." European Review for Medical and Pharmacological Sciences, vol. 17, no. 4, 2013, pp. 4930–4940, https://www.europeanreview.org/wp/wp-content/uploads/4930-4940.pdf.

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31. Leproult, Rachel, and Eve Van Cauter. "Effect of One Week of Sleep Restriction on Testosterone Levels in Young Healthy Men." Journal of the American Medical Association, vol. 307, no. 21, 2012, pp. 2177–2179, https://jamanetwork.com/journals/jama/fullarticle/1029127.

32. "Sleep and Testosterone: The Connection." Sleep Foundation, 2023, https://www.sleepfoundation.org/physical-health/sleep-and-testosterone.