The best essential oils for the sauna are those with a clear, fresh scent: eucalyptus, peppermint, pine and spruce, plus citrus oils, lavender and lemon balm. They never go neat onto the sauna heater. Instead, they are mixed with a solubiliser and added to the infusion water in high dilution. The simplest and safest option is a ready-made infusion concentrate with dosage instructions.
A lot of what you read online about essential oils in the sauna cannot be backed up. This article sticks to what can be said with confidence: which oils fit, what is in a sauna oil and what to watch out for when using it.
What essential oils are
Essential oils are volatile fragrances from plants. They are usually obtained by steam distillation from leaves, needles, flowers or wood; citrus oils are made by pressing the peel. Each oil is a mixture of many individual substances. Some of them shape its typical smell:
- 1,8-cineole in eucalyptus
- menthol in peppermint
- limonene in citrus peel
- linalool in lavender
- α-pinene in conifers
Why we perceive such scents so quickly and directly is explained in the article The science of scent.
Sauna oil, infusion concentrate, essential oil: the difference
These terms are often mixed up. They refer to three different things.
A pure essential oil is 100 per cent oil. It does not dissolve in water but floats on top. If you add it to the sauna bucket, it lands on the hot stones almost undiluted when you pour.
In shops, sauna oil and infusion concentrate usually mean the same thing: a mixture of fragrances and a solubiliser that disperses in water. According to a study by the German Social Accident Insurance (DGUV), the fragrances are mostly essential oils, dissolved in ethanol or isopropanol. According to safety data sheets, the alcohol content is mostly between 50 and 95 per cent.
There are also alcohol-free infusions, in which an emulsifier disperses the oils in water. The same applies to all variants: they are diluted in water as directed by the manufacturer and never used neat.
Which essential oils suit the sauna
Eucalyptus, mint, menthol
These are the classics. Eucalyptus oil smells clear and slightly camphor-like, mainly because of 1,8-cineole. Peppermint oil and menthol create a cool sensation even though the temperature stays the same. The reason is well researched: menthol activates a cold receptor called TRPM8. The 2021 Nobel Prize in Physiology or Medicine was awarded for the discovery of temperature receptors such as this one.
Many promises are made about the effect on the airways. The German consumer organisation Stiftung Warentest has stated that scents in a sauna infusion mainly serve well-being and that their effect is not comparable to inhalation. So if you like eucalyptus, choose it for its scent.
Conifers
Pine, spruce, mountain pine, Swiss stone pine and fir smell of forest. What they have in common is a high proportion of monoterpenes such as α-pinene. They suit a wooden cabin and combine well with eucalyptus or mint.
Citrus, lavender, lemon balm
Orange, lemon, bergamot and grapefruit smell lighter and brighter. Lavender and lemon balm make a blend softer. Many people choose combinations like these for the evening or for the last round.
Strong oils
Thyme, juniper, clove and star anise are very intense. They work well as an accent in a blend; on their own and at high doses they quickly become overpowering.
Our three infusions are composed from these groups, with real essential oils. Larimar Breeze combines eucalyptus, mint and menthol with wintergreen and pine needle. Verdelite Uplift combines eucalyptus, mint and orange with notes of green tea, lavender, star anise and clove. Obsidian Glow is built on orange, lemon and citronella with lavender and lemon balm.
Using essential oils safely
Never neat on the heater
Essential oils and the alcohol in infusion concentrates are flammable. That is why none of it belongs undiluted on the hot stones, let alone the heater itself. Heater manufacturers such as Harvia state in their manuals that only fragrances specifically made for sauna water may be used, and that the instructions on the pack apply.
Dilute as directed
Germany's Federal Institute for Risk Assessment (BfR) points out that almost all essential oils should only be used in highly diluted form. According to the BfR, concentrations that are too high can irritate the skin or cause breathing difficulties. For the infusion, this means sticking to the dosage; for our concentrates, 10 ml per litre of water. How to mix and pour the infusion water is described in the article How to make a sauna infusion.
Take care with young children
According to the BfR, potent substances such as camphor or menthol are generally not suitable for babies and toddlers. For children under three, the BfR advises particular caution with eucalyptus and peppermint oil. If young children are nearby, it is better to skip infusions with these oils.
Allergies
Allergic reactions to essential oils are also possible, the BfR writes. Stiftung Warentest advises people with a fragrance allergy to avoid scented infusions. If an infusion product contains certain allergenic substances above a set amount, the label carries the statement "May produce an allergic reaction". This is required by the European CLP Regulation.
Storage
Keep bottles tightly closed, cool and dark, out of the reach of children. The BfR explicitly names child-resistant closures as a protective measure. Undiluted oils do not belong on the skin either.
Natural, pure, synthetic
"Essential" means that an oil has been obtained from plants. Many infusions combine essential oils with synthetic fragrances to make a scent rounder or longer-lasting, or to add notes that don't exist as an oil. That in itself is neither good nor bad. What matters is that the ingredient list is honest and the advertising matches what the label says.
Whether an infusion contains only natural fragrances can be checked in the ingredient list. Ours says "with real essential oils", because some of our scent notes also come from synthetic fragrances.
How to recognise a good infusion product
- It is expressly made for sauna infusions.
- The bottle states how much concentrate goes into one litre of water.
- The fragrances are named, and allergy statements and hazard symbols are on the label.
- You can follow how far it goes. At 10 ml per litre, 333 ml makes about 33 litres of infusion water, which is over 200 ladles.
Frequently asked questions
Can you use any essential oil in the sauna?
No. The best choices are eucalyptus, peppermint, conifers, citrus oils, lavender and lemon balm. Very intense oils such as thyme or clove are better as a small part of a blend. Pure oils also need a solubiliser so that they disperse in the infusion water.
Are undiluted essential oils dangerous in the sauna?
Yes. Essential oils and alcohol are flammable and never go neat onto the hot heater. Heater manufacturers such as Harvia only permit fragrances made for sauna water, and these are diluted in water as directed.
What is the difference between sauna oil and infusion concentrate?
Usually none. Both terms describe a mixture of fragrances and solubiliser that goes into the infusion water. A pure essential oil, by contrast, does not dissolve in water.
Which oils suit the evening?
In the evening, many people choose warmer, softer scents: orange and lemon with lavender or lemon balm. Cool scents such as mint and menthol fit better at the start.
Can young children be present during a eucalyptus infusion?
For children under three, the BfR advises particular caution with eucalyptus and peppermint oil, and it considers menthol and camphor generally unsuitable for babies and toddlers. With young children nearby, it is better to skip such infusions.
Three scents, with real essential oils
Larimar Breeze is clear and cool, Verdelite Uplift herbal and fresh, Obsidian Glow warm for the evening. Each bottle contains 333 ml of concentrate, dosed at 10 ml per litre of water. Made in Germany, composed in Zurich.
