Query not calling data from table?

[liamloveslearning]

im trying to call all users from a database with the same interests as the current, logged in user on my website.

 

I have the following

// Get Session USER interest
$interestsquery  = "SELECT `interest` FROM `user_interests` WHERE `user_id` = " . $usersClass->userID();
$result = mysql_query($interestsquery);

$interests = array();
while(list($interest) = mysql_fetch_array($result))
    $interests[] = $interest;
    $interest1 = $interests['1'];
    $interest2 = $interests['2'];
    $interest3 = $interests['0']; 
// END INTERESTS



//USers with Same Interests
$interests_query = "SELECT * FROM produgg_users
join user_interests on produgg_users.id = user_interests.user_id
where interest = '$interest1' and produgg_users.id != '".$usersClass->userID()."'";
$interests_result = mysql_query($interests_query) or die(mysql_error());

if($interests_result != 0) {
    while($interests_row = mysql_fetch_array($interests_result, MYSQL_ASSOC))
    {
        echo $interests_row['user_id'];
    } 
}
else
{
    print "No users to display!";
}
//END SAME INTERESTS

 

which doesnt bring back any data, yet if I add (beneath //USers with Same Interests) $interest1 = 'footy';

 

the interests_query seems to work, can anybody see where im going wrong?