SaunaBox's Detox and Hormone Claims: Where Is the Product-Specific Evidence?

Edited by: Melanie Green, Health and Wellness Copywriter · Registered Dietitian Background · MSc Human Nutrition.
Expert contributor: Jennifer King, DNP, Doctor of Nursing Practice · Certified Fitness Professional.
Clinically reviewed by: Dr. Joe Lee, DPT, OCS · Duke University Doctor of Physical Therapy · Board Certified Orthopedic Clinical Specialist.
Published November 12, 2026. All figures checked against the live sources on November 11, 2026.

The short answer

SaunaBox's Solara pages say infrared heat helps flush heavy metals and toxins through sweat and helps regulate melatonin, cortisol and other hormones, and they cite no study. Research on comparable saunas finds trace metals in sweat but only weak evidence that body levels fall, and hormone responses that are short-lived or fade with regular use.

The claims

Health statements on the Solara 1-Person and Solara 2-Person product pages, read November 11, 2026

Claim, Paraphrased Section Study or Citation on the Page
Infrared heat helps flush out heavy metals, toxins and impurities through sweat Detoxification None
The sauna supports the endocrine system and helps regulate melatonin, cortisol and other hormone levels Hormonal Balance None
Regular infrared sessions help regulate cortisol and calm the nervous system Improved Sleep None

The hormone statement is worded as established science: the page says the effect "has been shown to" occur. The same pages carry the standard notices that their statements have not been evaluated by FDA and that the product is not intended to diagnose, treat, cure or prevent any disease.

The documents the pages do link are an Intertek certificate for electromagnetic field testing and a Proposition 65 component test report. Both concern the sauna's materials and electrical emissions. Neither concerns a health effect.

Two different heavy metal statements

The Solara pages use the words heavy metals in two unrelated ways, and only one has a document behind it.

  • The sauna's parts are free of them. SaunaBox says components were tested for lead, cadmium and phthalates, and links a report. This is a materials claim with a lab document.
  • The sauna removes them from your body. This is a physiological claim with no document.

A reader skimming the page could take the lab report as support for both. It supports the first only.

What counts as relevant evidence

Evidence for these claims does not need SaunaBox's name on it. Research on a comparable sauna can apply. What it has to match is the device, an infrared cabin with a published maximum of 158°F, and the claim: that sessions lower the amount of a metal in the body, or keep a hormone in a healthier range. The table sorts what we found by both.

Published research we located on November 11, 2026, by how closely it matches the device and the claim

Source Sauna Type What Was Measured Bearing on the Claim
Genuis and colleagues, 2011, 20 adults Infrared sauna for 10 participants, steam sauna for 7, exercise for 3 Toxic elements in blood, urine and sweat, each sampled once Partial. Found many toxic elements in sweat, some at higher concentrations than in blood or urine, and concluded that induced sweating appears to be a potential method of elimination. It did not track whether body levels fell.
Sears and colleagues, 2012, systematic review of 24 reports Various ways of collecting sweat Arsenic, cadmium, lead and mercury in sweat Partial. Found the metals in sweat and said sweating deserves consideration. On body levels it found little: one mercury poisoning case treated with chelation and then months of sweating, one study in which rowing lowered blood lead, and one abstract on sauna and lead. It calls for properly sized trials.
Kuan and colleagues, 2022, 12 adults Heated sauna cabinet at 45°C, type not stated, compared with treadmill running Five metals in sweat Partial. Nickel, lead, copper and arsenic concentrations were lower in sauna sweat than in exercise sweat; mercury did not differ.
Baker, 2019, comprehensive review Sweating in general How much sweat contributes to excretion Direct. Concluded that sweating's role in eliminating waste products and toxicants seems minor next to the kidneys and gastrointestinal tract.
Ahokas and colleagues, 2023, 16 male athletes, randomized crossover Infrared sauna set to 50°C, measured at about 43°C (109°F); one 20-minute session after training Cortisol, testosterone and growth hormone the next morning; overnight heart rate variability; sleep diary Device matches. Next-morning cortisol was statistically unchanged after the sauna session and fell after passive rest, but the size of the change did not differ significantly between the two. Testosterone and growth hormone did not differ. The authors concluded the session did not appear to influence hormonal balance.
Ahokas and colleagues, 2025, 40 female athletes in matched pairs, not randomized Infrared sauna at 50°C for 10 minutes after training, over a 6-week program Morning saliva cortisol, overnight heart rate and heart rate variability, in the first and last week Device matches. In the first week, cortisol rose the morning after a sauna session and did not in the control group. By the sixth week that response was gone, which the authors read as adaptation to the heat.
Huhtaniemi and Laukkanen, 2020 and Kukkonen-Harjula and Kauppinen, 1988, reviews Finnish sauna Many hormones around a session Device differs. Hormone levels shift during and after a session and return to normal within hours; responses shrink in regular users. The 2020 review lists melatonin as showing no change.
Podstawski and colleagues, 2021, young men Finnish sauna sessions with cold water immersion Cortisol, testosterone, DHEA-S, prolactin before and after Device differs. Cortisol was lower right after the sessions; the other three did not change significantly.
Hussain and Cohen, 2018, systematic review of 40 studies Dry saunas Clinical effects in general Context. Only 13 of the studies were randomized trials and most were small; the authors called for better data.

Heavy metals: what the research adds up to

The claim is not invented. Metals are measurable in sweat, including sweat produced in an infrared sauna, and two of the papers above treat sweating as a route worth studying. Researchers disagree about how much it matters: the one review that weighs sweat against the kidneys and gut rates its contribution as minor.

The thinner part of the record is whether sauna use lowers the amount of a metal in the body. The studies above mostly measured what was in sweat. The 2012 review, which we read in full, found three reports that go further:

  • A 1978 case in which a worker poisoned by mercury vapor was given chelation therapy and then months of daily sweating, after which the mercury level in the patient's sweat returned to normal and the patient recovered.
  • A study in which endurance rowing lowered blood lead in occupationally exposed men.
  • A Russian abstract reporting that sauna use increased lead in sweat and improved patients' condition.

A single case that also involved chelation, an exercise study and an abstract are weak support for a sauna claim, and the review's own authors say properly sized trials are still needed. We found no trial showing that infrared sauna use lowers body levels of a metal.

The product page's wording, that infrared heat helps flush heavy metals out, is stated with more confidence than that record supports.

Hormones: what the research adds up to

The two closest matches to the Solara are infrared sauna studies from one research group. In the 2023 trial, a single 20-minute session after training left next-morning cortisol statistically unchanged, while cortisol fell after passive rest; the size of the change did not differ significantly between the two conditions. In the 2025 study, the first week of post-exercise infrared sauna use raised next-morning cortisol, and by the sixth week of regular use that rise was gone.

So the picture is more than a shift that fades within hours. With regular infrared use, the body's cortisol response to the sauna adapted over weeks. That is adaptation to a repeated stress. Neither study showed cortisol held in a healthier range, and neither measured melatonin.

Research on Finnish saunas, which the 2021 paper describes as running at 80 to 100°C (176 to 212°F) against the Solara's published 158°F maximum, shows hormone levels moving during and after a session and settling within hours. On melatonin, the 2020 review of that research lists it as showing no change during sauna bathing, and we found no peer-reviewed study that measured melatonin after infrared sauna sessions; a PubMed search for infrared sauna melatonin on November 11, 2026 returned no results.

These studies do not establish sustained improvement in abnormal cortisol or melatonin levels. They describe temporary shifts, an early stress response that fades with regular use, or no difference.

Is there evidence specific to the SaunaBox Solara?

We found no published study that used a SaunaBox product, and the product pages cite none. That alone would not settle the question, because research on comparable infrared cabins can apply. It is the comparable research, summarized above, that falls short of the two claims as SaunaBox words them.

SaunaBox may hold testing it has not published, or rely on studies it has not linked. If it publishes or sends citations, we will add them here.

Limits of this review

  • Our search covered PubMed and the open web on November 11, 2026. It was not a systematic review, and relevant studies may have been missed.
  • We read four of the papers in full: the 2012 review, the 2022 sweat study, the 2023 infrared trial and the 2020 endocrine review. The others were read from abstracts and repository records.
  • The two infrared studies came from one research group, used sessions cooler than the Solara's published maximum, and studied young athletes after training. Both were supported in part by a sauna manufacturer. Other groups of people, or other session lengths, could give different results.
  • No clinician has reviewed our reading of these studies.

What SaunaBox documents well

  • The product pages carry the FDA notice and do not claim to treat a disease.
  • The materials claims come with documents from a named testing company.
  • The published maximum temperature is consistent across both Solara product pages.

A category-wide habit

Detox and hormone language is common across infrared sauna marketing, and SaunaBox is not alone in using it. That does not change the test. A claim about what a sauna does inside the body needs research that matches the device and the claim, or it should be worded as a possibility.

Questions to settle before you buy

  1. Which studies support the heavy metal statement, and did any measure metal levels in the body before and after sauna use?
  2. Which studies show an effect on melatonin?
  3. Has the Solara, or a cabin with the same heaters, been used in any study, published or not?
  4. Does shown mean shown for infrared saunas, or for saunas in general?

SaunaBox's published terms and specifications are covered in our document-based SaunaBox review.

Bottom line

The Solara's detox and hormone lines are presented without sources, and the research we found on comparable saunas is more cautious than the page. Sweat carries trace metals, but we found no trial showing that sauna use lowers body levels; the closest evidence is one case report. Hormone responses to a sauna are short-lived or fade with regular use, and neither infrared study showed cortisol held lower. On that record, the research does not support buying a sauna to lower a heavy metal level or correct a hormone. Those are questions for a clinician.

Sources and verification

Every source below was read on November 11, 2026.

  1. SaunaBox, Solara 1-Person product page. Detoxification, Hormonal Balance and Improved sleep statements; linked documents; notices.
  2. SaunaBox, Solara 2-Person product page. Same statements; published maximum temperature.
  3. Genuis SJ, Birkholz D, Rodushkin I, Beesoon S. Blood, urine, and sweat (BUS) study: monitoring and elimination of bioaccumulated toxic elements. Archives of Environmental Contamination and Toxicology, 2011.
  4. Sears ME, Kerr KJ, Bray RI. Arsenic, cadmium, lead, and mercury in sweat: a systematic review. Journal of Environmental and Public Health, 2012.
  5. Kuan WH, Chen YL, Liu CL. Excretion of Ni, Pb, Cu, As, and Hg in sweat under two sweating conditions. International Journal of Environmental Research and Public Health, 2022.
  6. Baker LB. Physiology of sweat gland function: the roles of sweating and sweat composition in human health. Temperature, 2019.
  7. Ahokas EK, Ihalainen J, Hanstock HG, Savolainen E, Kyröläinen H. A post-exercise infrared sauna session improves recovery of neuromuscular performance and muscle soreness after resistance exercise training. Biology of Sport, 2023. Hormone results are in the paper's hormone table and discussion.
  8. Ahokas EK, Kyröläinen H, Ihalainen JK, Hanstock HG. Salivary cortisol response to post-exercise infrared sauna declines over time. Temperature, 2025.
  9. Huhtaniemi IT, Laukkanen JA. Endocrine effects of sauna bath. Current Opinion in Endocrine and Metabolic Research, 2020.
  10. Kukkonen-Harjula K, Kauppinen K. How the sauna affects the endocrine system. Annals of Clinical Research, 1988.
  11. Podstawski R, et al. Endocrine effects of repeated hot thermal stress and cold water immersion in young adult men. 2021.
  12. Hussain J, Cohen M. Clinical effects of regular dry sauna bathing: a systematic review. Evidence-Based Complementary and Alternative Medicine, 2018.
  13. PubMed searches for infrared sauna melatonin and for SaunaBox, both returning no results.

Method and limits

This is a document review. We read the pages listed above on the morning of November 11, 2026, Pacific time, and report what they said then, naming the page section each figure came from so a reader can find it or see that it has changed. We did not buy or test a SaunaBox product, and we did not contact SaunaBox for comment. SaunaBox revises its pages (its help center return article showed an update within the week before our check), so wording may have changed since; the linked page controls. Where two SaunaBox pages disagree, we print both and do not choose between them. Statements that we did not find something describe our reading on that date and are not proof of absence. Nothing here states or implies that SaunaBox acts in bad faith or that its products are unsafe. Links to saunabox.com carry rel="nofollow" because of the competitive relationship disclosed above. If SaunaBox publishes a correction or sends one, we will update this page and log the change. This article is not medical advice.

More SaunaBox record checks

This article is one of eight document reviews of SaunaBox's published terms and claims. Our earlier record check of the complaint history is here: SaunaBox Complaints (2026). The other seven:

FAQs

Does the SaunaBox Solara remove heavy metals from the body?

SaunaBox's product page says infrared heat helps flush out heavy metals through sweat, but cites no study. Published research finds trace metals in sweat, including infrared sauna sweat. We found no trial showing that sauna use lowers body levels of a metal; the closest evidence is one case of mercury poisoning treated with chelation and then sweating. A 2019 review concluded sweating appears to be a minor route for eliminating toxicants.

Does the SaunaBox Solara balance hormones?

SaunaBox's page says infrared sauna use helps regulate melatonin, cortisol and other hormones, without a citation. In a 2023 trial, one infrared sauna session did not significantly change next-morning cortisol. In a 2025 study, cortisol rose after early sessions and that response faded over six weeks of regular use. Neither established a sustained improvement in cortisol levels, and neither measured melatonin.

Does SaunaBox cite studies for its health claims?

Not on the Solara product pages. When read on November 11, 2026, the detox and hormone statements had no study, footnote or reference. The pages link an Intertek EMF certificate and a Proposition 65 component test report, which concern materials and emissions.

Is the SaunaBox Solara free of heavy metals?

SaunaBox says the Solara's components were tested for lead, cadmium and phthalates and links a test report. That is a claim about the sauna's materials. It is separate from the claim that using the sauna removes heavy metals from the body.

Does evidence for a sauna health claim have to come from that brand's sauna?

No. Research on a comparable sauna can apply. What matters is whether the study matches the device type and the claim being made. For the Solara's claims, the comparable research we found measured metals in sweat and hormone responses around sauna sessions. It does not establish lower body levels of metals from sauna use, or sustained improvement in cortisol or melatonin levels.