Oops, it doesn't look like 'Doughnut Running day' is a national day..

Other days

unicorn

Unicorn Day
singles

Singles Day
lumpy rug

Lumpy Rug Day
ponytail

Ponytail Day
bounce

Bounce Day
bow tie

Bow Tie Day
coffee

Coffee Day
boy friend

Boy Friend Day
boba

Boba Day
gum

Gum Day