Top 100 words to NOT 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
amazing
Anything that looks like you are YELLING
apply now
As seen
As seen on Oprah
As seen on TV
avoid
Be your own boss
Buy
Call now
cash bonus
cialis
Click here
Collect
Compare
consolidate
Contains $$$
Contains word “ad”
credit
Dear Friend
discount
don’t delete
Double your
Double your income
E.x.t.r.a. Punctuation
earn
Earn $
earn extra cash
easy terms
Eliminate debt
extra income
fast cash
financial freedom
For Only
for you
FREE
Free
Free access
free gift
free info
Free Instant
free offer
Free Samples!
Friend

G a p p y T e x t
Get
Get out of debt
Hello
herbal
Hidden
home based
Hot
Information you requested
Instant
levitra
Life Insurance
limited time
Loans
lose
lose weight
Lower your mortgage rate
Lowest insurance rates
make money
medicine
mortgage
multi level marketing
notspam
Now only
numerical digits at the end
Offer
Online degree
online marketing
Online pharmacy
only
Open
opportunity
Promised you
Refinance
Removes
reverses
satisfaction
Search engine listings
serious cash
Starting with a dollar amount
Stop or Stops
Teen
Undisclosed recipient
valium
vicodin
winner
Work from Home
xanax

source: "The Seven Dirty Words you can't say in subject lines; plus 100 others you shouldn't use either." SubscriberMail. 2006.