Turn off Salesforce Chatter Recommendations

In case Chatter recommendations interferes with a record's or file's privacy, system administrators can submit a case to support to turn the feature off. Before submitting a case, an admin must provide the following:
 

• The type of recommendations a system administrator wants to turn off and an explicit statement that as a system administrator you would like the features turned off. Choose between records, files, people, group, trending topics, or all.

• Organization Id where the said feature will be turned off (Find your Salesforce Organization ID).

• Brief explanation as to why you need the said feature turned off.