I researched and there are many theories out there but I like this one the best:
Historically the US Navy switches from their white uniforms to their navy ones at this time of the year. Let’s use this as the basis.As much as I respect the US Armed Forces, we can’t live our fashion lives around them. Therefore, toss that rule/myth out the window and feel free to wear as much white as you want all year around.
White is refreshing and gives your dark fall and winter colors a needed lift. Enjoy!