Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_31 (goals_against INTEGER, points VARCHAR, goal_difference VARCHAR)

### Question ###
What is the lowest goals against value for a team with 83 points and a difference over 50?

### Accurate SQL ###

SELECT MIN(goals_against) FROM table_name_31 WHERE points = 83 AND goal_difference > 50