Short answer
Yes, but only briefly. Small Finnish studies found that hot, long sauna sessions raised growth hormone in the blood for a short time, in one study up to 16-fold in men. The rise faded with repeated days, and no study shows it builds muscle or slows ageing. Longer, hotter sessions also raise the risk of overheating.
Growth hormone often comes up in sauna discussions, usually with impressive numbers attached. Those numbers come from real but small studies, and they say less than many articles claim. Here is what the research actually measured and what it means for a normal sauna session.
What growth hormone is
Growth hormone is made by the pituitary gland at the base of the brain. In children it drives growth, and in adults it helps regulate body composition and metabolism. The body controls it tightly: too little or too much both cause problems. For example, the NHS describes acromegaly, a rare condition caused by too much growth hormone.
What the studies found
| Study | Who | Sauna exposure | Growth hormone result |
|---|---|---|---|
| Leppäluoto et al., 1986 | 10 men (7 women for other hormones) | 80°C dry sauna, 1 hour twice a day for 7 days | About 16-fold rise in men; the response declined after day 3 |
| Kukkonen-Harjula et al., 1989 | 8 young men | 80°C and 100°C until discomfort, and 80°C becoming humid until exhaustion | Rose in the 100°C session |
| Mero et al., 2015 | 10 active men | 30 min far-infrared or traditional sauna at 35–50°C | Rose in both; highest right after the sauna and 30 min later |
In the 1986 Finnish study, ten healthy men sat in an 80°C (176°F) sauna for an hour twice a day for a week. Their blood growth hormone rose about 16-fold. The rise was smaller after the third day, and the authors suggested it may be linked to dehydration from the heat.
The 1989 study put eight young men through three hot sessions. Growth hormone went up in the 100°C (212°F) session. The same study recorded heart rate rises of about 60 to 130 percent and large increases in stress hormones such as noradrenaline.
In a 2015 study from the University of Jyväskylä, ten active men were tested after strength and endurance training and in 30-minute far-infrared and traditional sauna sessions at 35–50°C. Growth hormone rose in both sauna types and was highest right after the sauna and 30 minutes later. Hard training also raised it on its own. The study was about recovery and did not measure muscle gain.
What the studies do not show
- They measured short-term blood levels, not long-term changes.
- They did not show more muscle, less fat or slower ageing.
- The groups were tiny, from 8 to 17 people, mostly young men.
- The biggest rises came from sessions far longer than anyone should do at home.
So the honest summary is that heat stress briefly raises growth hormone, the same way it raises several other hormones. That is a sign your body is under strain, not proof of a benefit. If you are interested in sauna and training, see do saunas help build muscle and do saunas boost testosterone.
Traditional sauna, infrared sauna and steam room
The large rises were seen in traditional Finnish saunas at 80–100°C. Cleveland Clinic puts traditional saunas at 150–195°F and infrared saunas at 110–135°F. Only one small study looked at infrared and growth hormone, and none of the studies here tested steam rooms. There is no evidence-based session plan for raising growth hormone in any of them.
Other hormones that change in the sauna
The same studies saw prolactin rise and cortisol fall in some sessions. In the 1986 study, prolactin rose more than four-fold in women, and five of the seven women had a temporary missed period after the week of twice-daily hour-long sessions. Hormone changes go both ways and are not all welcome.
Sauna safety
Harvard Health advises keeping sessions to about 15–20 minutes, avoiding alcohol, drinking water afterwards and cooling down gradually. Leave at once if you feel dizzy, sick, confused or get a headache, which the NHS lists as signs of heat exhaustion. See our sauna tips and how often and how long to use a sauna.
Frequently asked questions
Do saunas increase growth hormone?
Yes, temporarily. In a 1986 Finnish study, men who sat in an 80°C sauna for one hour twice a day had about a 16-fold rise in blood growth hormone. The level fell back afterwards, and the response weakened after the third day.
How much does a sauna raise HGH?
It depends on how hot and long the session is. A 1989 study saw growth hormone rise in a 100°C session but not in an 80°C session that ended when people felt uncomfortable. The 16-fold figure came from much longer, repeated sessions.
Does a higher growth hormone level after sauna build muscle?
There is no evidence for that. The studies only measured short-term changes in blood levels. They did not show more muscle, less fat or better recovery from those spikes.
Does an infrared sauna raise growth hormone?
In a 2015 study of 10 active men, growth hormone rose during 30-minute far-infrared and traditional sauna sessions at 35–50°C and was highest right after the sauna and 30 minutes later. The study looked at recovery, not muscle growth, and the group was very small.
How long should I stay in a sauna?
Not as long as the studies did. Harvard Health suggests limiting sessions to about 15–20 minutes, avoiding alcohol and cooling down gradually. Leave earlier if you feel dizzy, sick or unwell.
Is it safe to try to raise growth hormone with a sauna?
Treat any hormone change as a side effect, not a goal. Very long, hot sessions increase the risk of dehydration and heat exhaustion. If you are thinking about growth hormone for a medical reason, talk to a doctor.
This article is general information, not medical advice.