The regular White potatoes are healthier than sweet potatoes because the regular white potatoes contain more potassium than sweet potatoes.
Sweet Potatoes and regular White Potatoes are both healthy and provide the same amount of nutrients, vitamins, minerals etc.
So by eating either sweet potatoes or white potatoes or regular potatoes you still get all the health benefits.
But when it comes to which one is healthier of the two types of potatoes the healthiest of the potatoes are the regular white potatoes.