Saunas can be a relaxing way to work off some stress and are very popular in gyms and can even be found in certain homes. Using a sauna too often, however, can have some adverse effects on your body and overall health.
General Negative Effects
There are numerous general negative effects that can potentially affect anyone who steps foot into a sauna for too long, typically over a half hour or so. These effects include dehydration from too much perspiration and not enough fluid intake, overheating that can lead to heat stroke or heat exhaustion, or through mineral depletion, which causes you to lose vital electrolytes and minerals through excess sweating.
There are various negative sauna effects that can be compounded by a previous medical condition. For example, saunas may interfere with the body's natural healing processes, so it's recommended that they be avoided within 48 hours or so of an injury such as a sprain. If you've previously had a heat stroke or have had a recent heart attack, the it is recommended that saunas be avoided completely. If you are on steroids for any reason, such as for a condition such as lupus, saunas can interfere with your blood circulation and will fail to distribute the drugs properly.
Saunas will interrupt the proper distribution of medicine applied with patches, such as nicotine patches; profuse sweating can cause the medicine to transfer into your skin at doses much higher than recommended. Saunas may also call unexpected fluctuations of insulin levels, so diabetics should always check their levels before and after using a sauna.