High CPU Usage for my own consolepplication client

Question

I was building a console application which acts as a client. It connects to the given ip address of server. I am using Raknet in it. One of the problems i noticed is that the program Consoleapplicationxx.exe is taking high CPU usage (as shown by the Task Manager). 45% and more.

So i examined by code and found Raknet works in a while loop. Following is my code (not exact. from my memory)

int main(int argc, char** argv)
{
    while (1)
    {
        for (packet->Receive(); packet; packet->Deallocate(), packet->Receive()
        {
            switch (packet->data[0])
            {
            case xx:
                break;
            case yy:
                break;
                    ...
            }
        }
    }
    //some stuff and end
}

So i created another console application. Below is the code

#include <iostream>
#include <windows.h>
int main()
{
    while (1)
    {

    }
}

When i run this program, it also uses high cpu. Then i added a Sleep(1000) inside the while loop and cpu usage reduced to 0%. i gradually reduced to sleep to 1 ms

#include <iostream>
#include <windows.h>
int main()
{
    while (1)
    {
        Sleep(1);
    }
}

And it works perfect(0% cpu usage). (Note: I tried putting Sleep(0) and it again high CPU usage 50%) So is this the way to solve this issue? So that i will add Sleep(1) to my original program?

I am planning to distribute the program after it is finished. So it is important to solve the issue.