Refining my database select - php

Question

GOAL:
Select from the database to target a team name from one of my five specific columns. the table has a number of columns 5 of which are headed respondent_team_1 to respondent_team_5. In each of those columns there maybe a string value that is repeated so the idea is to look at that columns and know this and just take the 1 distinct value and not all so I can match up the data like so:
CODE:
<?php
$sql = "SELECT distinct respondent_team_1 FROM respondent_data WHERE dashboard_id = $user_dash_id";
$result = $conn->query($sql);
if($result->num_rows > 0){
while($row = $result->fetch_assoc()){
echo $row["respondent_team_1"];
}
}
?>
<br>
<?php
$sql = "SELECT distinct respondent_team_2 FROM respondent_data WHERE dashboard_id = $user_dash_id";
$result = $conn->query($sql);
if($result->num_rows > 0){
while($row = $result->fetch_assoc()){
echo $row["respondent_team_2"];
}
}
?>
<br>
<?php
$sql = "SELECT distinct respondent_team_3 FROM respondent_data WHERE dashboard_id = $user_dash_id";
$result = $conn->query($sql);
if($result->num_rows > 0){
while($row = $result->fetch_assoc()){
echo $row["respondent_team_3"];
}
}
?>
<br>
<?php
$sql = "SELECT distinct respondent_team_4 FROM respondent_data WHERE dashboard_id = $user_dash_id";
$result = $conn->query($sql);
if($result->num_rows > 0){
while($row = $result->fetch_assoc()){
echo $row["respondent_team_4"];
}
}
?>
<br>
<?php
$sql = "SELECT distinct respondent_team_5 FROM respondent_data WHERE dashboard_id = $user_dash_id";
$result = $conn->query($sql);
if($result->num_rows > 0){
while($row = $result->fetch_assoc()){
echo $row["respondent_team_5"];
}
}
?>
SUMMARY:
What I am trying to do is refine all those code blocks into one code block as A it is messy and B there must be a better way but I am unable to find one?
I have tried various methods, the obvious being take the column names I need and make a select against them, I tried to use the GROUP BY keyword with no luck either. Im not looking for somebody to do this for me but just some wisdom or advice would be excellent.