My athlete’s foot and other fungi

About 20-25 % of the world population suffers from fungal infections of the skin and nails. That is around 1.5 billion people (world population clock HERE). This fact instantly made me feel better about my own reoccurring athlete’s foot. I am not alone.

What is athlete’s foot?

For a Swede or a German (and most likely other nationalities too) the name “athlete’s foot” sounds a bit peculiar. We translate this condition as “foot fungus” or simply “foot mushroom”; this makes many English speaking people raise their eyebrows. Maybe Swedes and Germans are a bit more straightforward with bodily functions compared with the more prudish English? (Oh, my! That was quite the generalization!).

Athlete's foot (image credit: Ellington). No, this is not my foot.

Athlete’s foot (image credit: Ellington). No, this is not my foot.

Though “foot mushrooms” may sound weird to some it accurately describes what it is: a skin fungus. The term “athlete’s foot” rather focuses on the process through which it may be acquired: wet and warm conditions favour growth of fungi. Since I exercise a lot, and judging by the Lab dog’s inclination to try constantly to lick my feet, I presume that I also perspire enough through my feet to make the fungal habitat the proverbial “hit”: wet and warm.

I have foot mushrooms.

Did you know there are many types of skin fungi?

As a biologist, and particularly as an ecologist, biological diversity generally pleases me. However when I realized the scope of the diversity of the foot fungal species my joy was somewhat dampened: so much itchy evil in the world!

There seems to be three different genera (a major subdivision of a family) of fungi that are responsible for fungal infections in humans: Trichophyton, Microsporum, and Epidermophyton.  These little buggers show a lot of genetic variation between the continents and also between geographical areas. This genetic diversity also makes them hard to fight since they may respond very differently to medications.

Mushroom: a fly agaric in Norway (image credit: By MichaelMaggs)

Mushroom: a fly agaric in Norway (image credit: By MichaelMaggs)

Who gets fungal infections?

You can get fungal infections through a variety of means: sweaty and hot trainers are good incubators for these organisms as is hot wet skin. These so called dermatophytes (fungi that like to grow on skin) thrive at temperatures of 25-28 °C which is mostly the range of one’s skin temperature. Household dust is also a reservoir of fungal spores. Even socio economic conditions can play a role since very crowded conditions can facilitate the transfer of any pathogen efficiently.

Fungal infections of the more serious kind can have devastating effects in communities with little or no access to proper medications. People with weakened immune systems such as AIDS are very susceptible to all infections including fungal.

A diet that is very high in monosaccharide sugars may favour fungal infections (this is however still disputed). Some people with recurring infections may be advised by their doctor to go on a carbohydrate-free (or low carb) diet for a few months to “starve out” the fungi. Please note that this is a medical intervention and should not be translated as carbohydrates are bad for all people or all carbohydrates cause fungal infections. They.are.not. Furthermore carbohydrates are a very large chemical family and there are vast differences between monosaccharide carbohydrates and oligosaccharide ones (read my article on the science of carbs HERE).

You can get a fungal infection as a gift from your friendly pet companion (yes I will blame The Lab dog for my foot despite it being the wrong species). Funnily some fungal species are referred to as “cuddly toy mycoses” because of the frequent appearance of these types of fungal infections in children. Even children’s’ toys can act as reservoirs for the spores (very loosely: the “seeds” of the fungi). Yes I will try to blame my foot fungus on The Spawn too.

The fungal body-part guide

You can get fungal infections basically everywhere ranging from the scalp, the feet, nails, intestines, and to the penis or vagina. Many fungal species like Candida spp. are naturally present in one’s body but sometimes a shift in the host/parasite balance can result in rapid growth of this fungus. This can be due to a variety of reasons such as intake of medicines like steroids or antibiotics as well as other causes such as obesity and diabetes mellitus. Anti-fungal medications and a strict low sugar diet over a few months usually sort it out but you need to contact your doctor before embarking on any such treatments.

You can get fungal infections everywhere. (Leonardo da Vinci: The Vitruvian man)

You can get fungal infections everywhere. (Leonardo da Vinci: The Vitruvian man)


Vaginal fungal infections are called thrush and are not, as some people think, sexually transmitted diseases. Stop spreading this nonsense! Almost every woman on this earth will get thrush at some point in her life. Some get this as a recurrent growth and this can have genetic and/or dietary reasons. Don’t freak out! Just go to the doctor and get some advice and don’t let any prick tell you that you are dirty or do not wash enough. It is the contrary: too frequent washing (like several times a day) with highly scented products is not good for you. Nonetheless, if you have thrush, to prevent re-infection if you are susceptible, your partner might also need treatment.

Vaginal douching involves an “internal shower” of the vagina (I actually had to Google this nonsense a few weeks ago) and can actually introduce pathogens into you and cause disease. The vagina is a pretty cool biological system and it is internally self-cleaning so there is no need for vaginal douching.

Tight synthetic underwear can also be a very good if your aim is to increase your total fungal biomass and abundance. The fungi can easily waterslide from the anus to the vagina resulting in fungal growth. Also synthetic materials do not breathe so the wet and warm conditions are just perfect for fungal sexy (reproduction) time. Mum and Granny were right: cotton wool panties are great! Bring out the Bridget Jones pants.

Did you know that many fungi are resistant to treatment?

Fungi have developed resistance against many anti-fungal medications. This is due to people not following the instructions given by their doctor. Resistance to treatment will develop if some fungi survive the treatment. This is often is the case if the medication is not taken with the correct frequency and length of time. It is paramount that one follows the instructions when taking serious medications like these or we, the human race, will lose our ability to cure serious fungal infections in the future.  (If you are interested in the development of antimicrobial resistance click HERE)

Here I am supposed to write a call-to-action, how about: “Tell me about your thrush or athlete’s foot: Was it itchy and did it go away after treatment?”

No, perhaps not, but have you reflected upon the use and misuse of antimicrobials and antibiotics in your country? Have you seen any changes in prescribing practices over the past few years? Do you think that we have already reached the “post antibiotic and antimicrobial era”?

A quick and easy way to get rid of your foot mushrooms, follow the advice of Madonna as given on David Letterman: pee on your feet in the shower. Note that this was irony.

Science Safely!

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...unfairly blames her athlete's foot on the dog.

…unfairly blames her athlete’s foot on the dog.

ps. Ringworm is not a worm, but a fungus.

Review: Havlickova, Blanka, Viktor A. Czaika, and Markus Friedrich. “Epidemiological trends in skin mycoses worldwide.” Mycoses 51.s4 (2008): 2-15.

Posted in Biology, Medicine, The Biology of Disgusting and tagged , , , .


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