Once you lose a heart, you can't eat anything but cake.

I lost a heart in survival and when I tried to eat bread, all it did was move, but I couldn't eat it. Next, I tried watermelon, and it did the exact same thing I was not able to eat it. Then I tried this again to see if this bug was just a coincidence, but it wasn't. When I tried to eat bread and watermelon again it did the same thing as the first time, I couldn't eat it.