If you've ever heard George Carlin's famous "Seven Dirty Words" you can't say on TV, you can safely avoid using all seven in your subject lines. They will definitely get you blocked.
Here is a list of 100 more that you should avoid using as well.
Top 100 words/phrases NOT to use in your subject lines:
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all words that relate to sex or pornography
all words that related to cures or medication
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anything that looks like you are YELLING
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as seen
as seen on Oprah
as seen on TV
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contains $$$
contains word "ad"
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Dear Friend
discount
don't delete
double your anything
double your income
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