Katy Perry, who is the most-followed user on Twitter, and Lady Gaga both lost around 2.5 million followers, while former US President Barack Obama saw his followers plummet by around 2.1 million.
According to the platform, the change has been made necessary in order to rebuild trust with users.
The issue centres on the recent interest in fake news, which has put social media platforms like Twitter under more scrutiny than ever.
Under the new measures, anyone whose account is locked for unusual activity, which includes things like sending an unusually high number of tweets, and did not reply to a prompt to verify their identity will now be excluded from follower counts.
Twitter spokeswoman Vijaya Gadde said: "Over the years, we've locked accounts when we detected sudden changes in account behaviour.
"In these situations, we reach out to the owners of the accounts and unless they validate the account and reset their passwords, we keep them locked with no ability to log in.
"This week, we'll be removing these locked accounts from follower counts across profiles globally. As a result, the number of followers displayed on many profiles may go down."