When you send an email or email a text document to a recipient, chances are good that the transmission of the document is unsecured.  That is, the document can be intercepted and viewed by someone. 

You may use the service at http://www.everpassword.com/aes-encryptor to encrypt or descript your text document.  The password should be delivered to the recipient in a safe way so when the recipient receives the encrypted message, he can use the same service to descript the text document. 

For instance, you may place the follow text in the box, 

High cholesterol can increase risk of breast cancer 

then give it a password "cholesterol", click on encrypt, you will have the encrypted message in the next box. 

U2FsdGVkX1/+kqNpywrjm2LmMDhKH8Hk92NQZ+zRpz8uH8D8lUK7rrIptEC5mp+Q

Iwx44J5VIXnSngWZbCZ6fssLFK4hxmRGYXLueY6TNsc=

you can place the encrypted message back in the first box, type cholesterol as the password and then click on descript, you can read the message again in the next box. 

The site does not assume any liability though.