Variable updates everywhere but Update function.

I have a variable "health" this is effected when damaged. When i debug.log the variable in the update function, it does not change, it still says the health = 100, but when i debug.log health in any other function, the variable is updated, but still stays the same in update.

 using System.Collections;
 using System.Collections.Generic;
 using UnityEngine;
 using UnityEngine.AI;
 public class enemyController : MonoBehaviour {
 
 
     private Vector3 origin;
     private GameObject player;
     
 
     private NavMeshAgent nMA;
 
     public enemyType enemyType;
     
     private bool isDead = false;
     private bool attackingState;
     private bool isAttacking;
     private float maxHealth;
     private float health;
     private int level;
     private float attackDMG;
     private Animator enemyAnim;
     private bool patrollingState;
     private bool isPatrolling;
 
     // Use this for initialization
     void Awake()
     {
        
 
     }
 
     void Start () {
         this.origin = this.gameObject.transform.position;
         nMA = this.gameObject.GetComponent<NavMeshAgent>();
         isAttacking = false;
         isPatrolling = false;
         attackDMG = enemyType.baseDamage;
         player = GameObject.FindGameObjectWithTag("Player");
         enemyAnim = this.gameObject.GetComponent<Animator>();
         level = enemyType.baseLevel;
         maxHealth = enemyType.maxHealth;
         health = 100;
     }
 
     public void switckIsAttacking()
     {
         if (isAttacking)
         {
             isAttacking = false;
 
         } else 
         {
             isAttacking = true;
         }
     }
 
     public float getHealth()
     {
         return health;
     }
 
     public float getMaxHealth ()
     {
         return maxHealth;
     }
 
     public float damageHealth(float dmg)
     {
         Debug.Log("damageHealth: " + health);
         if (!isDead) {
             health = health - dmg;
         }
         
         return health;
     }
     
     public void Die()
     {
         nMA.isStopped = true;
         enemyAnim.SetBool("Dead", true);
     }
 
     public float getDamage()
     {
         return attackDMG;
     }
 
     public void Attacking()
     {
         
        if (!isDead)
         {
             
             if (this.gameObject.tag == "cQBEnemy" && Vector3.Distance(this.gameObject.transform.position, player.gameObject.transform.position) <= 3)
             { 
                 nMA.isStopped = true;
                 this.transform.LookAt(player.transform);
                 enemyAnim.SetBool("Attacking", true);
             } else
             {
                 nMA.isStopped = false;
                 nMA.SetDestination(player.transform.position);
                 enemyAnim.SetBool("Attacking", false);
                
 
             }
 
         }     
         
     }
 
     public void patrolling()
     {
         StartCoroutine("patrollingWaitTime");
     }
 
     IEnumerator patrollingWaitTime()
     {
         isPatrolling = true;
         nMA.SetDestination(new Vector3(Random.Range(origin.x-3, origin.x+3), 0, Random.Range(origin.z-3, origin.z+3)));
         yield return new WaitForSeconds(Random.Range(5, 10));
         patrolling();  
     }
 
     public void Kill()
     {
         Destroy(gameObject);
     }
 
     public void checkStates()
     {
         if ( Vector3.Distance(this.gameObject.transform.position, player.gameObject.transform.position) <= 20)
         {
             isPatrolling = false;
             patrollingState = false;
             attackingState = true;
         } else
         {
             if (Vector3.Distance(this.gameObject.transform.position, player.gameObject.transform.position) >= 20)
             {
                 attackingState = false;
                 if (Vector3.Distance(this.gameObject.transform.position, this.origin) >= .5f)
                 {
                     if (!isPatrolling)
                     {
                         nMA.SetDestination(origin);
                         patrollingState = false;
                     }
                     
                 } else
                 {
                     if (Vector3.Distance(this.gameObject.transform.position, this.origin) <= .5f)
                     {
                         if (!patrollingState)
                         {
                             
                             patrollingState = true;
                             patrolling();
                         }
                     }
                 }
                 
 
                 
             }
             
             
         }
     }
 
     public void checkHealth()
     {
         if (health <= 0)
         {
             Debug.Log(this.gameObject.name.ToString() + " " + health);
             health = 0;
             isDead = true;
             Die();
         }
     }
     
     
     // Update is called once per frame
     void Update () {
         Debug.Log("Update: " + health);
         checkStates();
         Vector3 vel = nMA.velocity;
         float speed = vel.magnitude; 
         enemyAnim.SetFloat("speedPercent", speed * 10);
 
        
 
         if (attackingState)
         {
             isPatrolling = false;
             patrollingState = false;
             Attacking();
         }
 
         checkHealth();
 
         
 
         
         
     }
 }