Infrared saunas are often marketed for weight loss, but their real benefits for metabolism go beyond just burning calories. By heating your core temperature and creating a light cardiovascular effect, they may help improve how your body manages energy, sugar, and fat.
Here’s a closer look at how infrared saunas support metabolic health—and how to use them safely and effectively.
Burning Calories Without Moving
When you're sitting in an infrared sauna, your heart rate goes up and your blood vessels expand. This mimics a light workout, which is why it’s sometimes called “passive cardio.” Your body starts sweating and works to cool down, and that process uses energy—burning some extra calories along the way.
While it won’t replace regular exercise, a 30-minute infrared sauna session can slightly increase your daily calorie burn. It may also boost your resting metabolism for a short time afterward, giving your system a little extra push. Just keep in mind that the immediate weight loss you see is mostly water. It’s the long-term effects, like better circulation and energy use, that really count.
Better Blood Sugar Control
Infrared sauna use has also been linked to improved insulin sensitivity. That means your body gets better at using insulin to lower blood sugar levels—a big deal for anyone at risk of diabetes or dealing with insulin resistance.
Studies suggest that repeated exposure to heat may have similar benefits to light exercise when it comes to blood sugar. One short study found that overweight adults who used heat therapy daily for 10 days showed lower fasting blood sugar and insulin levels. Their bodies simply handled glucose better.
Why does heat help with this? The stress from heat may trigger anti-inflammatory effects and the release of proteins that help protect insulin pathways. Also, better blood flow means insulin and glucose can get where they need to go more efficiently. After a sauna session, your body might even shift into a temporary fat-burning mode, supporting a healthier metabolism overall.
Helps Your Body Burn More Fat
Infrared saunas can also encourage your body to use fat for fuel. Some research shows that during and after a sauna session, your body taps into fat stores to meet its energy needs. In a small study, participants saw a drop in cholesterol and triglycerides after just a couple of weeks of regular heat therapy, suggesting their bodies were processing fat more efficiently.
Stress can interfere with metabolism, especially when cortisol (a stress hormone) stays high. Sauna use is known to reduce stress and promote relaxation, which may indirectly help you manage weight. Better sleep and mood also make it easier to stay consistent with healthy habits.
Could Help With Metabolic Syndrome
Metabolic syndrome is a group of risk factors—including high blood pressure, high blood sugar, poor cholesterol levels, and belly fat—that raise your chances of heart disease and diabetes. Regular sauna sessions may help reduce these risks.
In observational studies, frequent sauna users had better blood pressure and cholesterol levels than people who used saunas less often. Infrared saunas may also lower inflammation in the body, especially markers like C-reactive protein (CRP), which is often elevated in people with obesity or diabetes. Less inflammation, better blood flow, and stronger insulin response all support metabolic health.
How to Get the Most Out of It
To use an infrared sauna for metabolic health, here are some tips:
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Frequency: Aim for 3 sessions per week to start. If you feel good, you can go up to 4–5 times a week.
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Session length: Start with 10 to 15 minutes, and work your way up to about 20 or 30 minutes if it feels comfortable.
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Temperature: Stick to a range of 45–60°C (113–140°F). You should be sweating but not struggling.
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Hydration: Drink water before and after each session. Avoid alcohol before sauna use.
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Pair with healthy habits: Saunas work best as a supplement to regular workouts and balanced meals. For example, using a sauna after exercise may help your body recover and add to the benefits.
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Listen to your body: If you feel dizzy or unwell, take a break. Everyone’s tolerance is different, and your body will adjust over time.
Final Thoughts
Infrared saunas aren’t a shortcut to weight loss, but they can play a helpful role in supporting your metabolism. They gently raise your heart rate, improve how your body uses sugar, and may even help you burn more fat. When combined with a healthy lifestyle, regular sauna sessions could help manage or prevent metabolic issues like insulin resistance and inflammation.
As always, talk to a doctor if you have a medical condition or are unsure about using a sauna. But if everything checks out, making saunas part of your weekly routine could be a relaxing and rewarding way to boost your metabolic health.
References
- Cisoń, T., Malik, L., & Wiecha, S. (2014). Effect of a single Finnish sauna session on white blood cell profile and cortisol levels in athletes and non-athletes. Journal of Human Kinetics, 39(1), 127–135. https://doi.org/10.2478/hukin-2013-0075
- Liao, W. C. (2002). Effects of passive body heating on body temperature and sleep regulation in the elderly: A systematic review. International Journal of Nursing Studies, 39(8), 803–810. https://doi.org/10.1016/S0020-7489(02)00023-8
- McCarty, M. F., Barroso-Aranda, J., & Contreras, F. (2009). Regular thermal therapy may promote insulin sensitivity while boosting expression of endothelial nitric oxide synthase: Effects comparable to those of exercise training. Medical Hypotheses, 73(1), 103–105. https://doi.org/10.1016/j.mehy.2008.12.020
- Pallubinsky, H., Scheuermann, K., Moffatt, C., et al. (2020). Passive exposure to heat improves glucose metabolism in overweight humans. Acta Physiologica, 229(4), e13488. https://doi.org/10.1111/apha.13488
- Southern Illinois University School of Medicine. (2022, April 12). 5 surprising health benefits of sauna use. SIU Medicine Blog. https://www.siumed.edu/blog/5-surprising-health-benefits-sauna-use
- Young, J. (2022, September 20). Infrared saunas: 6 health benefits. Cleveland Clinic Health Essentials. https://health.clevelandclinic.org/infrared-sauna-benefits
