Damage Over Time Help?

Sorry, please have mercy on my extreme noobiness. I need help with a damage over time code, preferably not a separate script. Basically I made a hunger and thirst bar using a tutorial, because I'm nooby like that, and i need them to degrade 1 hunger point/thirst point (out of total 100 hunger/thirst points) every 10 seconds unless it's already full, but no matter how much I try myself, I can never get it to work, all i need is a tiny little code snippet. I'm so sorry for asking for a premade thing, but I'm really desperate... All I know is that it has something to do with:

 "Time.deltaTime;" 

and

 "while(curHunger < maxHunger)

     curHunger - 1"

Or something like that.

This is the code I use for my hunger bar, it was modified from BergZurgArcade's Health Bar...

 using UnityEngine;
 
 using System.Collections;
 
  
 
 public class PlayerHunger : MonoBehaviour {
 
     public int maxHunger = 100;
 
     public int curHunger = 100;
 
     
 
     
 
     public float hungerBarLength;
 
  
 
     // Use this for initialization
 
     void Start () {
 
         hungerBarLength = Screen.width / 4;
 
     }
 
     // Update is called once per frame
 
     void Update () {
 
         AdjustCurrentHunger(0);
 
     }
 
     
 
     void OnGUI(){
 
         GUI.Box(new Rect(5, 540, hungerBarLength, 20), curHunger + "/" + maxHunger);
 
     }
 
     
 
     public void AdjustCurrentHunger(int adj){
 
         curHunger += adj;
 
         
 
         if(curHunger < 1)
 
             curHunger = 0;
 
         
 
         if(curHunger > maxHunger)
 
             curHunger = maxHunger;
 
         
 
         if(maxHunger < 1)
 
             maxHunger = 1;
 
         if(curHunger <= 0)
 
             Destroy(gameObject);
 
         hungerBarLength = (Screen.width / 4) * (curHunger / (float)maxHunger);
 
     }
 
 }

BY THE WAY, I NEED THE CODE SNIPPET TO BE IN C# Thanks in advance for your co-operation!