How often do you change your bed sheets? Once a week? Every fortnight? Once a month? It’s one of the most widely debated topics – but a more important question is how often do you vacuum your mattress? If your answer is never, you’re definitely going to change your cleaning habits after reading this. A doctor has gone viral on TikTok after revealing the reason why you should always vacuum your mattress, and it’s so disgusting. Why you should vacuum your mattressDr. Karan Raj responded to a video in which a guy vacuumed his mattress for the first time and showed the huge amount of dust that gat…