thanks

I didn't know it was "hold" not "click"

thanks

You may be thinking that whenever you eat the food, you don't regain health. that isn't the case. now in 1.8 there is a hunger bar, and when you're eating the food, it's probably not high enough to have you gain health. and if you know about the hunger bar, then it's probably what grizzly said,

Hold down the right-mouse key.
End of starvation.