The main fungus toenail cause is poor condition. That doesn't necessarily mean that your feet are in a poor/ dirty condition, no, what it means is that the feet are not in their optimum condition. So the feet can be clean but sweaty and this is a great cause especially in athletic, adolescent, and within active people.
If you are on medication that reduces your body's natural defenses- like chemo therapy, then there is a likeliness that you are going to be more prone to toenail fungus.
2- Certain conditions.
Now this one gets ignored by medical professionals an awful lot. If you have something like Diabetes then you are going to be at a higher risk of toenail fungus. This is, simplistically because Diabetes does three things:
a- It reduces your body's own defenses.
b- It affects a part of your nervous system that affects how you sweat. Normally your skin is slightly supple. Because your nervous system is controlling how you sweat and when. With Diabetes that sweating mechanism is affected. Therefore you can either get a sweaty or a dry foot. A sweaty foot increases the likeliness of fungus infection and a dry foot becomes cracked and the skin loses its suppleness, so a fungus can jump straight in.
c- You may also have an excess of sugar running around your body and especially on your skin. For the fungus, it basically acts as gravy that adds to the flavor of the meal. Unfortunately these three factors are great environments for toenail fungus, and skin fungus, to thrive within patients who have certain medical conditions.
3- A reservoir.
Fungus toenails usually comes from somewhere and the most common area is from your skin, socks and shoes. The skin is the main culprit. Sometimes people will have Athletes Foot. This is usually found on the bottom of the foot or inbetween toes (usually a red area of itching, maceration (white moist skin) and small pin prick dots). Now if you have a toenail fungus it sometimes comes from the Athletes Foot, and if you have Athletes Foot then you may have a toenail fungus. To treat and find out about Athletes Foot click here: Athletes Foot 101
4- Family members.
A fairly common toenail fungus cause, spouses usually pass on their problem to their partner. If you have a toenail fungus then it might be a good idea to check other members of your family. Check in between their toes and around their feet and look for Athletes Foot as well. Remember that sharing anything from towels, shoes, and socks can pass on the fungus.
5- Non-Sterile Tools. This is where nail care technicians and even family members can pass on the fungus to unknowing people. Fungal spores are hard to kill, so tools, in a professional environment, must first be cleaned to get rid of the debris within the tools (sometimes with an ultrasonic cleaner) then autoclaved- nothing less. If they don't use an autoclave then walk away. Check with them, ask them to show you how they clean their tools. It is also worthy to note that scrubbing tools is not the best- because the rubbish gets stuck onto the bristles and gets transferred from one tool to the next.
At home it is more difficult because you won't have that type of equipment, so make sure that you have 2 pairs of nail clippers. One for your fungus toenail nails and the other for regular nails.