What follows is an excerpt from my book about my High Dose Vitamin D3 experiment over a 1-year period. I describe my almost life long quest to cure the yellow toenail fungus (also known as – onychomycosis) that one can pick up from running around barefoot in the gym showers. After years and years of trying various treatments I accidentally discovered that high dose Vitamin D3 will cure under-the-nail yellow toe nail fungus. It takes as long as it takes for your toe nails to grow outcompletely-about 9 months in my case. You can put Rogaine (minoxidil) on the nails each day to make them grow out faster if you are in a hurry.