How to retrieve date from mysql database in php?

[impin]

i have table cresults.

email    marks    last_submit
[e-mail]    9    2013-05-24
[e-mail]    5    2013-05-24
[e-mail]    5    2013-05-24
[e-mail]    8    2013-05-24
 

$sql1="SELECT * FROM cresults where email='$login_session'";
$result1=mysql_query($sql1);
$last_submit=mysql_result($result1,"last_submit");    
    echo " $last_submit";
    if($last_submit==$today)
    {
        echo"you have already submitted";
    }

but this code

echo " $last_submit";

not displaying the date. it displaying the email id. why? whats wrong in the code?!

if i use like this

$sql1="SELECT last_submit FROM cresults where email='$login_session'";

it works fine...
why?!