Your Gut is Your Second Brain. Here’s How Infrared Sauna Supports It.

Your gut helps guide your immune system, and influences inflammation, metabolism, and mood. It can even play a role in how well you age.¹ Functional medicine practitioner Dr. Will Cole puts it simply. "In functional medicine, we know that when the gut is out of balance, everything is out of balance."

When our gut is balanced, our digestion is calm and we have steady energy. But when gut health is off, it can manifest as abdominal pain, bloating, irregularity, and cause issues such as leaky gut, as well as compromise immune health. This is why gut health should be considered whole-body health. It's also why supportive daily rituals, like infrared sauna therapy, deserve consideration.

Sunlighten co-founder Connie Zack, who has spent 25 years studying infrared, sees gut health the same way as Dr. Cole. She says, "The healthier your gut, the more signals it sends to your brain. This can help with mental clarity, better decisions, and happier outcomes.”

Your gut is one of the body's command centers for immunity, inflammation, metabolism, and energy. Much of its influence travels along the gut-brain axis, a two-way line of communication between your digestive system and your brain. The messenger is the vagus nerve, the longest nerve in your body. It carries signals in both directions, all day long.

At the center of this sits your microbiome. This is the vast community of trillions of microorganisms including bacteria, fungi, and viruses, living in your gut.² A healthy microbiome is diverse and balanced. It helps you absorb nutrients, regulate hormones, and keep your immune system working well. It also shifts constantly, responding to the food you eat, the time of day, and any medications you take, especially antibiotics.
When that shift becomes imbalanced, it's called gut dysbiosis. This drives bloating, inflammation, and digestive issues, along with effects on mood and immunity.

Gut issues show up in a lot of everyday conversations. Here's a look at some common ones.

• Leaky gut. A weakened gut lining becomes too permeable. Gaps form between cells, letting undigested food and bacterial byproducts slip into the bloodstream.³ This can trigger immune reactions and inflammation.
• Irritable bowel syndrome or IBS. Irritable bowel syndrome is a gut-brain disorder marked by pain, bloating, constipation, or diarrhea.
• Small intestine bacterial overgrowth or SIBO. SIBO is a buildup of bacteria where it doesn't belong. It can drive bloating, gas, and irregular digestion.
• Inflammatory bowel disease or IBD. This includes Crohn's and ulcerative colitis, involves real inflammatory damage and requires medical care.
• Bloating and constipation. Everyday complaints are often shaped by hydration, stress, movement, fiber, and routine.

None of these conditions have a single quick fix, but many share common threads: inflammation, stress, or a nervous system stuck in fight or flight. That's exactly where infrared sauna therapy can help.

While Infrared sauna therapy doesn't act directly on your gut, it supports the systems your gut depends on. Dr. Cole describes the effect as “akin to calming a disrupted forest, restoring harmony and vitality to the ecosystem.” Here's how the heat and light effects of infrared sauna therapy may affect key pathways.

• A calmer inflammatory response: Chronic, low-grade inflammation is closely tied to gut imbalance.
  
  Infrared sauna may help bring that inflammation down. Far-infrared sessions have been shown to lower oxidative stress in people with cardiovascular risk factors.⁴ Lower inflammation was also linked to passive heat exposure with traditional (Finnish) sauna use.⁵ By supporting a calmer inflammatory baseline, infrared saunas may create a better internal environment for the gut to do its job. As Dr. Cole puts it, “reducing systemic inflammation allows the lining of the gut to heal.”
  
  
• Support for your natural detox pathways: Your gut works alongside your liver, kidneys, lymphatic system, and skin.
  
  Dr. Cole points to the gut-liver axis here. “Your gut and liver are always in communication,” he explains, “working together to clear out excess hormones, pathogens and environmental chemicals. When toxins build up faster than the body can eliminate them, the liver can become overwhelmed, and this leads to negative effects on the gut.”
  
  Infrared sauna therapy promotes a deep, productive sweat. And sweat is a real elimination route. A study of blood, sweat and urine found that certain toxic elements show up in sweat, sometimes at higher concentrations than in blood or urine.⁶ Lowering that toxic burden, Dr. Cole says, “reduces the strain on both the liver and the gut, allowing the gut-liver axis to work more efficiently.”
  

• Better circulation to the gut: Better blood flow means better delivery of oxygen and nutrients, including to your digestive tract.⁷
  
  Dr. Cole explains it directly. "Better circulation means improved oxygen and nutrient delivery to tissues, including the digestive tract. Nitric oxide also supports vascular health, which improves microcirculation in the gut and supports repair of the intestinal lining.” Sunlighten's SoloCarbon^® heaters are shown to raise core body temperature by up to three degrees.⁸   This helps boost the circulation that supports the gut’s digestion, repair, and resilience.
  
  
• A shift from "fight or flight" to "rest and digest": When your body is stuck in stress mode, digestion suffers.  
  
  Your gut and brain stay linked through the vagus nerve, which runs your "rest and digest" signals. Dr. Cole explains that infrared sauna sessions have been shown to activate the vagus nerve, helping to shift the body from fight-or-flight mode to a parasympathetic state where digestion works best. “This is crucial for proper digestion and microbiome balance,” he says.
  
  
• Heat, cellular repair, and leaky gut: When your body heats up, your cells respond by producing heat shock proteins.
  
  Heat shock proteins (HSPs) are a group of proteins that have a protective function in our cells, helping them to become stronger and more resilient under stress. That matters for your gut lining, which depends on strong, resilient cells to absorb nutrients and keep unwanted substances out of the bloodstream.
  
  Any heat source activates HSPs, and you don't need extreme temperatures to tap into these healing pathways. Infrared also supports the mitochondria, the energy centers inside your cells.⁹ As Dr. Cole explains, "infrared light stimulates mitochondrial function, enhancing cellular repair and energy production in intestinal cells.”

Ask Dr. Will Cole about gut health and the conversation quickly widens. He makes the point plainly: "…true health isn't just about what you eat — it's also about how you feel."

Supporting your gut microbiome goes beyond diet and supplements. Stress, sleep, mood, and nervous system balance can all shape how your gut functions. Giving your body repeatable moments of warmth, relaxation, and recovery are part of the process. In his own clinic, Dr. Cole says he's seen lowered inflammation and a genuine mood lift in patients who make infrared sauna a regular habit.

It isn’t a quick fix, he says; it’s a lifestyle change. "I look at an infrared sauna as an often game-changing component of a holistic gut reset," he adds. He's seen it become the missing link for patients dealing with toxic buildup and chronic stress, especially when paired with dietary and lifestyle changes.

"When you're ready to get started, I always recommend easing in, especially if you're new to infrared sauna therapy. Regular sessions of 10–30 minutes are great, so I would start with 10 and work your way up, listening to your body as you go along. You can also start with a lower heat setting and gradually increase. It's important to consume lots of water and make sure to replenish your electrolytes." — Dr. Will Cole, functional medicine practitioner

The best wellness routine is the one you enjoy and return to. In a Sunlighten sauna, infrared starts working the instant you turn your sauna on, and you don’t need intense temperatures to feel the benefits. Begin gently. Dr. Cole calls it "low and slow."

A simple approach to build from:

• Ease in. Start with 10-minute sessions at a lower temperature.
• Find a rhythm. Work toward four to five sessions a week.
• Hydrate well. Drink water before and after and replenish electrolytes.
• Layer calm. Dr. Cole often uses sauna time for breathwork or meditation, which can deepen the "rest and digest" effect.
• Pair it with the basics. Infrared works best alongside whole foods, fiber, and quality sleep.
• Listen to your body. Pause if you feel dizzy or depleted.

A note on safety: Check with a qualified healthcare professional before starting sauna use if you are pregnant, have cardiovascular concerns, manage a medical condition, or take medications that affect blood pressure or sweating.

When you decide to make infrared part of your gut-support routine, the quality of your sauna matters. And it’s important to understand the difference between traditional and infrared saunas. Traditional saunas heat the air, while infrared penetrates more deeply than warmed air. Traditional sauna heat doesn't possess light energy while infrared does. This light works at a cellular level, and why infrared offers benefits that traditional saunas don’t.

Sunlighten builds on that difference. The mPulse Intelligent Sauna is powered by the PulseIQ infrared intelligence platform. Instead of blending everything into a single general output, PulseIQ delivers red light, near-, mid-, and far-infrared separately, so your body absorbs the right energy when and where it needs it most. Plus, Sunlighten saunas are crafted from hypoallergenic, fragrance-free woods and designed with low EMF and low VOC construction. It's a standard the company set from the very beginning, and part of why Dr. Cole uses an mPulse at home.

The gut influences how you feel, how you think, and how you age. Supporting it is one of the most meaningful investments you can make in your long-term health. And it doesn't have to be complicated.

Connie says that quiet time in a Sunlighten sauna can help in so many ways, and it's effortless. "Reset your body. Reset your mind. Let infrared do the work so your body recovers safely and naturally," she says.

Ready to bring infrared into your routine? Explore the mPulse Intelligent Sauna and discover a more supportive way to feel your best, from the inside out.