I have three funtion which describe the brightness of three LEDs. I want the seconde loop run 1 second after the first one and the third 1 second after the second one. One loop needs approximately 5 seconds. So basically I need to run three loops separated. How is this possible?

I have three funtion which describe the brightness of three LEDs. I want the seconde loop run 1 second after the first one and the third 1 second after the second one. One loop needs approximately 5 seconds. So basically I need to run three loops separated. How is this possible?

Update: So I have this code running which I can compile but does not work:

int LED = 3;  
int LED2 =10;
int LED3 = 9;

bool loop1state, loop2state, loop3state; // True if running, false if off
int  loop1index, loop2index, loop3index; // Iterator values
int  periodIndex = 0; // starting with 0, increasing every 10 ms


void setup()
{
Serial.begin(9600);
}

void loop()
{
// Update loop enablers.
switch(periodIndex)
{
case 0:
 loop1state = true;
 loop1index = 0;
 break;

case 1000:
 loop2state = true;
 loop2index = 0;
 break;

case 1500:
 loop3state = true;
 loop3index = 0;
 break;

case 4000:
 periodIndex = 0;
 break;
}

if (loop1state)
{
 for (loop1index = 0; loop1index<255; loop1index++){
  analogWrite(LED,loop1index);
 }

 loop1state = loop1index < 256;
 }

 if (loop2state)
 {
 for(loop2index = 0; loop2index<255; loop2index++)
 {
  analogWrite(LED2,loop2index);
 }
 
 loop2state = loop2index < 256;
}

 if (loop3state)
 {
 for(loop3index = 0; loop3index<255; loop3index++)
 {
  analogWrite(LED3,loop3index);
 }
 loop3state = loop3index < 256;
 }
 delay(10);
 }