The Role of Saunas in Acne

One question that frequently arises is can sweat cause pimples? The cause of acne cannot be summed up simply, but research has indicated that the onset of acne vulgaris is due to an overgrowth of bacteria which disrupts the skin’s balance of bacteria. Propionibacterium acnes has been given a great deal of attention in how it may lead to clogging of pores in the skin and has even proven to produce enzymes that interact with oils produced in the skin, causing the formation of pimples.^[1-3] Oils produced by skin cells, known as sebocytes, are a primary influencer in the formation of acne. Research has indicated that when acne is present, there is an increased amount of sebum production.^[4,5] The argument has been made that although P. acnes and increased sebum production are causative agents in the formation of the lesions of acne (known as comedones and pimples), it has been shown that the process is greatly complicated by many factors.

A positive note is that although the origins of acne can be complex, treatment approaches do not have to be. The tradition of sauna goes back 2,500 years and has shown to have beneficial effects on human skin. Measurements taken of participants’ skin in a study examining the effects of sauna demonstrated that regular sauna not only reduces skin sebum production but also contributes to changes in skin pH regulation.^[6] Normal skin pH ranges from 4 to 5.5. A drop in the skin’s pH observed with sauna could affect desquamation or strengthen the skin’s Acid Mantel, responsible for skin integrity and cohesion. Additionally, this makes the environment harder for P. acnes to grow compared to the other bacteria on the skin.^[6,7]

Human sweat has shown to contain abundant antimicrobial peptides. Dermcidin, a protein found most commonly in sweat, can prevent the proliferation of P. acnes by reducing the bacteria’s ability to create RNA and proteins necessary to survive.^[8-10] Not only has dermcidin proven to actively kill P. acnes, but research has also tied the presence of acne to the decreased expression of dermcidin in sweat.^[11] This correlation suggests that the increase in sweat produced from time spent in the sauna could help to suppress the overgrowth of P. acnes. 

What Are Some of the Other Benefits of the Steam Room? 

Other benefits of sauna for the skin include an increase in both hydration and circulation.^[6] A drop of vascular resistance in the skin during a steam session helps with blood flow that could assist in the process of healing and ensure that epithelial cells are getting the nutrients they need to remain healthy.^[12] An almost two-fold increase in skin hydration can be detected with sauna and can benefit epidermal function, combating any notion that regular sauna could possibly dry out the skin.^[6]

Sauna has regularly shown to have several physiological benefits. These include decreases in blood pressure and increases in metabolic activity and oxygen consumption.

What Are Safety Concerns of Sauna? 

Sweat content is still being studied extensively to see if the content can be analyzed to predict medical conditions or diseases.^[13,14] Interleukin-1 alpha and beta cytokines, inflammatory molecules produced by the sweat gland cells that can recruit immune cells, increase in sweat during sauna.^[15]  This could lead to exacerbation of conditions that allow the cytokines from sweat to infiltrate the epithelial barrier and cause inflammation, like the disruption found in atopic dermatitis. Amino acids are lost in the sweat.^[16,17] At 45 minutes into a sauna bath, sweat from young men was measured for amino acid content and demonstrated a 55% decrease from the initial measurement taken at 15 minutes.^[16] As a result, if dietary protein levels are low, use of sauna could result in a net negative nitrogen balance, leading to poorer protein synthesis. Electrolyte loss is significant and may lead to imbalances in the blood. New users are recommended to exercise caution. Examination of electrolyte loss through sweat has additionally shown that regular sauna users lose less during sauna bath than novel users, suggesting that sweat content is adaptive and changes with continued sauna use.^[6] Anyone with heart or blood vessel related conditions such as unstable angina, aortic stenosis, orthostatic hypotension, or a recent heart attack should be careful before using saunas.^[12]

What Is the Verdict?

Sauna is a valuable tool for not only chronic disease, but also has a seemingly great potential for combating and preventing acne. More studies are indicated and needed. With the availability of this treatment, further exploration of steam room and acne will be possible. In particular, it is still unclear how different types of acne may respond to sauna. For example, inflammatory acne (with more pimples and pus-filled bumps) may respond differently than comedonal acne (with more whiteheads and blackheads). Since saunas have the potential to worsen different forms of acne and should be used carefully in certain health conditions, you should discuss sauna therapy with a qualified health provider before starting with sauna.  

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