Why Detoxing Matters: Chris Kresser on Ancestral Health, Infrared Saunas & Living Well in a Toxic World

“Detox” is one of those wellness terms that seems to show up everywhere—from celebrity-endorsed juice cleanses to trending supplements on Instagram. While some of these detox trends are more hype than help, ancestral health expert Chris Kresser says the principle of detoxing is grounded in biology—and more important today than ever. As a licensed acupuncturist, bestselling author, and renowned functional medicine practitioner, Kresser was well-equipped to answer WellBe’s questions around why detox is essential, how ancestral health offers a blueprint for modern wellness, and why tools like sauna therapy and infrared light can support your body’s natural detox pathways. Read on to learn key takeaways from our interview with Chris Kresser.

*This is a short clip from our interview with Chris Kresser. Click here to watch the whole thing.*

You can also listen to an audio version of our interview with Chris Kresser on The WellBe Podcast. 

What Is Ancestral Health?

Most people have heard of the Paleo diet, but fewer know that it stems from a broader philosophy called ancestral health. Rooted in evolutionary biology, ancestral health is based on the premise that every living organism—including humans—evolved to thrive in a specific environment. Remove that organism from its original environment, and problems arise.

“It turns out the same thing is true for humans,” says Kresser. “We evolved in a natural environment that’s radically different from the one we’re living in today.”

Thousands of years ago, our ancestors lived outdoors, walked 10,000–15,000 steps daily, and engaged in vigorous physical activity like hunting and foraging. They ate nutrient-dense whole foods—meat, fish, vegetables, fruit, nuts, and seeds—and were deeply connected to nature’s rhythms, with daily exposure to sunlight and rest after dark. Socially, they lived in tight-knit tribes, providing a deep sense of community.

Today, most of us are sedentary, eat ultra-processed foods, stay indoors, experience chronic stress, and are glued to screens late into the night. According to Kresser, this creates what’s known as an evolutionary mismatch—and it has serious health consequences.

“We’re not genetically designed for this world,” he explains. “You don’t need to live in a cave or give up electricity, but making small adjustments that move you closer to that ancestral template can have profound effects on your health.”

One of the most powerful places to start? Supporting your body’s natural detoxification systems.

Why Detoxing Is More Important Than Ever

There’s a common critique that detoxing is unnecessary because our bodies already do it—and that’s true, but only in part. “Absolutely, our bodies do perform detoxification on their own,” Kresser confirms. “That’s part of our natural evolutionary heritage.”

Your liver, kidneys, digestive tract, lymphatic system, and skin are all involved in filtering and eliminating toxins. These systems work together to break down harmful substances and remove them through urine, feces, and sweat. But while this natural capacity exists, Kresser emphasizes that it evolved in a very different environment—one with dramatically less toxic exposure.

Today, humans are bombarded with toxins that didn’t exist in the ancestral environment. PFAS chemicals, microplastics, pesticides, mold toxins, flame retardants, and heavy metals like mercury and lead are now ubiquitous in air, food, and water. According to the Environmental Working Group, over 280 industrial chemicals have been found in newborns’ umbilical cord blood.

“Our detox systems weren’t designed to handle this level of exposure,” says Kresser. “The burden has exceeded our biological capacity.”

Lifestyle factors compound the issue. Chronic stress, lack of movement, poor sleep, and a diet low in key nutrients all suppress detox function. Stress, for instance, floods the body with cortisol, diverting resources from systems like detoxification to survival. Inadequate sleep disrupts the brain’s glymphatic system, which clears toxins and waste from the central nervous system.

“When you add all that together, most people are likely not detoxing optimally,” Kresser says. That’s why actively supporting your body’s detox pathways has become essential in the modern world.

The Best Way to Detox: Kresser’s Four Pillars

Kresser emphasizes that detox isn’t about extreme cleanses or quick fixes. Instead, it’s about creating the right conditions for your body to do what it’s already designed to do. He breaks this down into four foundational lifestyle “pillars:”

1. Nutrition. Many detox processes require nutrients like B vitamins, selenium, zinc, and antioxidants such as glutathione. Unfortunately, the modern diet is often high in sugar and processed food, which not only lack these nutrients but actively work against detox by increasing inflammation and gut permeability (aka “leaky gut”).

Kresser recommends eating a whole-food, anti-inflammatory diet. While Paleo is his go-to, any approach that emphasizes unprocessed, nutrient-dense foods—like leafy greens, cruciferous vegetables, high-quality protein, and fermented foods—can support detox pathways. Studies show that diets rich in these nutrients improve liver enzyme function and help eliminate environmental toxins.

2. Movement. Physical activity increases circulation, promotes lymphatic drainage, and stimulates digestion—all of which help carry toxins out of the body. Even low-impact activities like walking, stretching, or yoga can support detox.

Movement also increases glutathione production, which plays a key role in neutralizing and removing harmful substances.

3. Stress Management. Chronic stress triggers sympathetic nervous system dominance—which means you’re constantly in a fight-or-flight state, and never activating your parasympathetic nervous system, or the rest-and-digest state. This impairs not only digestion but also detoxification, which your body considers to be a less essential function than fighting for survival. Over time, this can lead to toxin buildup and inflammation, among other issues.

Kresser advocates for stress-reducing practices such as breathwork, mindfulness meditation, journaling, nature exposure, and emotional regulation techniques. These support the parasympathetic nervous system, which helps to restore balance and enables the body’s healing processes.

4. Sleep. Sleep is when the body detoxes most effectively. The brain’s glymphatic system is only fully active during sleep, flushing out cellular waste and toxins. Poor sleep impairs this process, leading to cognitive issues and toxin accumulation.

“You can eat perfectly and exercise daily, but if you’re not sleeping well, you’re missing a key piece of detox,” Kresser says. He recommends seven to nine hours of high-quality sleep per night, ideally in alignment with circadian rhythms.

Herbs and Sauna Detox: Ancient Tools with Modern Power

Kresser recommends both herbs and saunas as tools to boost detoxification in your body—two approaches that are backed by research. But many cultures relied on these modalities to support detoxification long before clinical studies confirmed their benefits.

Herbal Medicine

Traditional detox herbs like milk thistle, burdock, and dandelion root have been used in both Eastern and Western herbalism for centuries. Research shows that these botanicals support liver function, reduce inflammation, and boost detox enzymes. “While our ancestors may not have understood the mechanisms, they clearly observed the benefits,” Kresser says.

Today, many functional medicine practitioners incorporate these herbs into detox protocols, often alongside supportive nutrients like N-acetylcysteine (NAC), curcumin, and alpha-lipoic acid.

Sauna Detox

One of the most effective and accessible detox tools Kresser recommends is sauna therapy. Cultures in Finland, Russia, and East Asia have long used saunas to promote vitality—and science backs them up.

“The skin is our largest organ, and sweating is one of the primary ways we release toxins,” Kresser says. Regular sauna use encourages deep sweating, stimulates circulation, and activates heat shock proteins, which help repair damaged cells and improve stress resilience.

Infrared Sauna Health Benefits

Infrared saunas use light to heat the body directly, allowing for deeper tissue penetration at lower ambient temperatures. Kresser explains that infrared therapy creates a unique combination of thermal and photobiomodulation effects.

Here’s how that works: infrared wavelengths activate receptors in your mitochondria (the “powerhouse” of the cell) called chromophores, which enhance cellular metabolism, reduce oxidative stress, and improve circulation — all of which support detox. These effects have been linked to benefits like:

• Reduced blood pressure
• Improved heart rate variability
• Lowered oxidative stress
• Enhanced mitochondrial function
• Mobilization of heavy metals like mercury and cadmium
• Reduced inflammation in chronic illness
  

So saunas are beneficial for your health in a lot of ways — and it seems as though the more you take saunas, the more benefits you reap. A Finnish study published in JAMA Internal Medicine found that people who used saunas 4–7 times per week had a 63% lower risk of sudden cardiac death than those who used them once weekly. Another study showed that two infrared sauna sessions per week over three months significantly reduced systolic blood pressure.

Kresser views infrared saunas as a modern evolution of ancestral detox practices. “They take what’s been used for centuries and apply it with precision and control,” he says.

The WellBe Takeaway: How to Detox Safely and Effectively

We get it—detox can feel like a confusing topic. But according to Chris Kresser, it all comes down to working with your biology, not against it. Here’s what to remember:

• Ancestral health is about alignment, not perfection. The goal is to mimic the environment your body evolved in, through things like sunlight, clean food, community, movement, and rest.
• Your detox systems are innate, but they’re overwhelmed in the modern world. Industrial chemicals, poor diet, and chronic stress weaken your body’s ability to clear toxins.
• There are four essential pillars of detox: — nutrient-dense diet, movement, stress reduction, and quality sleep. These are your detox foundation. Build these habits first.
• Ancient tools like herbs and sauna therapy are still powerful. Modern science validates their ability to boost detox enzymes, support liver function, and improve resilience.
• Infrared saunas offer additional benefits, including deep tissue detox, hormonal modulation, and improved circulation.
• It’s about consistency, not quick fixes. Detox isn’t a 3-day cleanse; it’s a daily, sustainable lifestyle.

Have you ever taken an infrared sauna? What was your experience like? Share in the comments below!

Watch our full interview with Chris Kresser to learn how our genes impact our detox ability, how much water he thinks you should drink, the link between detox and chronic disease, the biggest mistakes he sees people make when they want to detox their bodies, which types of detox are best for different types of toxins, what detox methods he thinks have gone too far, and much more.

You can also listen to an audio version of our interview with Chris Kresser on The WellBe Podcast.

Citations:

1. Laukkanen, T. et al. Association Between Sauna Bathing and Fatal Cardiovascular and All-Cause Mortality Events. JAMA Intern Med. 2015;175(4):542-548.
2. Hussain, J. et al. Clinical Effects of Regular Dry Sauna Bathing: A Systematic Review. Evid Based Complement Alternat Med. 2018; 2018: 1857413.
3. Lin, C. et al. Far Infrared Therapy Inhibits Vascular Endothelial Inflammation via the Induction of Heme Oxygenase-1. Arteriosclerosis, Thrombosis, and Vascular Biology. 2008;28:739–745.
4. Wong-Riley, M. et al. Photobiomodulation Directly Benefits Primary Neurons Functionally Inactivated by Toxins. Published, JBC Papers in Press, November 22, 2004.
5. Gryka, D. et al. The effect of sauna bathing on lipid profile in young, physically active, male subjects. Int J Occup Med Environ Health. 2014 Aug;27(4):608-18.

The information contained in this article comes from our interview with Chris Kresser, M.S., L.Ac. a licensed acupuncturist, functional medicine practitioner, and ancestral health expert. He is the co-director of the California Center for Functional Medicine, and founder of The Kresser Institute, which trains functional health practitioners and coaches. He is also the creator of the ADAPT Practitioner and Health Coach Training Programs, which have trained over 2,000 health professionals around the world. He has written several bestselling books, including The Paleo Cure and Unconventional Medicine. You can read more about Chris Kresser here.