Try this (usually at this point I'd have two versions, HTML and plaintext):
<cfsavecontent variable="content"><cfinclude template="content.cfm"></cfsavecontent>
<cfmail to="#user.email#" from="sender@somewhere.com" subject="Message from #sender_name#" type="html">
<cfmailpart type="html">#content#</cfmailpart>
</cfmail>
Also wrap content.cfm inside <cfoutput></cfoutput>