My health wont regenerate (easy mode)

I have been playing on my mincraft world for a while now. It has been set up on easy mode the whole time. When I take fall damage or get hit by a mob, I try to eat so my health will regenerate. It doesn't regenerate each time. I genuinely find this frustrating. I have to kill myself in order to get a full health bar. I don't understand what is happening. What should I do to fix this?