“Warning” on Emails by Sending Service

When sending out a Newsletter using MailPoet, at the top of the emails being received (by Gmail and possibly others) there is the below “Warning” message to those receiving. Is there any way to avoid this?

“Warning” This may be a spoofed message. The message claims to have been sent from your account, but Gmail couldn’t verify the actual source. Avoid clicking links or replying with sensitive information, unless you are sure you actually sent this message. (No need to reset your password, the real sender does not actually have access to your account!)