Social media stars including Kim Kardashian, Justin Bieber, and Charlie D'Amelio are among the celebrities whose Instagram followers have a more negative attitude towards their self-esteem, an internal Facebook study published by the Wall Street Journal reported.

According to the post, Facebook knew its apps were harming the mental health of some teenage girls and young users.

A study surveyed 100,000 people in nine countries, including the United States, Australia and Brazil.

Facebook spokesman said respondents were not asked to name specific accounts, but the researchers found that celebrity accounts were among the most viewed accounts of people who said they had experienced either higher or lower levels of negative social comparison on Instagram, AP reported.

He noted that the results make sense as each of the listed celebrities has over 30 million followers. Facebook researchers have not investigated whether using celebrity accounts leads to negative emotions towards themselves.

Facebook researchers found that singer Ariana Grande and model Kendall Jenner were among the celebrities whose followers considered social comparisons to be more negative.