If "x" then do nothing?

This might be the most poorly designed script but is there anyway to stop the script from doing anything at a certain point? As I want to stop the script when health reaches the maximum value of 100.

 #pragma strict
      
 var tex1 : Texture;
 var tex2 : Texture;
 var tex3 : Texture;
 var tex4 : Texture;
 var health : float;
 private var enterCollider : boolean = false;
 
 //Damage collider
 function OnTriggerEnter (Col : Collider)
 {
     if(Col.gameObject.tag == "Player")
     {
         enterCollider = true; 
     }
 }
 
 //Normal state
 function OnTriggerExit (Col : Collider)
 {
     if(Col.gameObject.tag == "Player")
     {
         enterCollider = false; 
     }
 }
 
 function Start()
 {
     //Initial Health
     health = 100;
 }
 
 function Update()
 {
     //Health countdown whilst in damage collider
     if(health > 0  && enterCollider == true)
     {
     health -= Time.deltaTime;
     }
     
     //normal health regeneration
     if(health > 0 && enterCollider == false)
     {
     health += Time.deltaTime;
     }
     
     //When health reaches 100 again, do nothing?
     if(health == 100 && enterCollider = false)
     {
     //Do Nothing?
     }
 }
      
 function OnGUI() 
 {
     if (health <= 100)
     {
       GUI.DrawTexture(Rect(0,0,Screen.width, Screen.height), tex1);
       }
       
       if (health <= 90)
     {
       GUI.DrawTexture(Rect(0,0,Screen.width, Screen.height), tex2);
       }
       
       if (health <= 80)
     {
       GUI.DrawTexture(Rect(0,0,Screen.width, Screen.height), tex3);
       }
       
       if (health <= 70)
     {
       GUI.DrawTexture(Rect(0,0,Screen.width, Screen.height), tex4);
       }
 }