A recent best-practices post at the Mailchimp website included information on three innocent, non-spammy words that harm e-newsletter open rates. The post said:
“An unexpected discovery in our analysis was the negative impact of three innocent words. Email marketers are familiar with words such as ‘free’ which are generally to be avoided in emails since they tend to trigger spam filters. We identified innocuous words that won’t trigger a spam filter, but will negatively affect your open rates. They are: Help, Percent off, and Reminder.”
I’m going to take Mailchimp’s word for it and add “Don’t use help, percent off, or reminder” to my e-newsletter checklist.