Getting Null Object Reference even though I'm not referencing an object

So I’m trying to use the unity ui text and it works fine except for recently I’ve been getting error saying I have a null object reference on the line where I define my statTextHealth variable even though I don’t reference any other object throughout the entire script

public int playerMaxHealth;
public double playerCurrentHealth;
public double defense;
public double strength;

private Text statTextHealth;
private Text statTextDefense;
private Text statTextStrength;

void Start () {
    playerCurrentHealth = playerMaxHealth;
}

void Update () {
    //This line right below this comment is the line the error is directing me to
    statTextHealth.text = ("Health: " + playerCurrentHealth.ToString());
    statTextDefense.text = ("Defense: " + defense.ToString());
    statTextStrength.text = ("Strength: " + strength.ToString());

    if (playerCurrentHealth <= 0) {
        gameObject.SetActive(false);
    }
}

public void PlayerDamage(int damage) {
    playerCurrentHealth -= ((double)damage / defense);
}

public void PlayerHeal(int heal) {
    playerCurrentHealth += heal;

    if (playerCurrentHealth > playerMaxHealth)
        playerCurrentHealth = playerMaxHealth;
}

NullReferenceException: Object reference not set to an instance of an object
CharStatManager.Update () (at Assets/Scripts/PlayerCharacterScripts/CharStatManager.cs:22)

Your statTextHealth is null; you must assign an instance of Text to it before you can access fields from it

I would suggest making it public and assigning your Text to it in the inspector, if possible