[colechristensen]

Honey contains glucose oxidase from bee guts, an enzyme that produces hydrogen peroxide in the presence of glucose and oxygen[1]. The accumulation of small amounts of H2O2 is what makes honey shelf stable.[2]

It's probably also what causes honey to have antibacterial properties when you put it on a wound.

That's not to say that it would have any effect on bacteria in your body if you eat it.

The enzyme is deactivated or denatured somewhere in the neighborhood of 50 C. [3]

Honey itself has antibacterial properties but there's no evidence I can find to show those properties translating to your body after you eat it. It makes sense that honey is effective to help treat wounds because it's still honey, not mixed up in your stomach and beyond. I'd bet stomach acid would do a fine job denaturing that enzyme as well, heat be damned. So maybe don't boil your honey if you're going to put it on a scrape, but drink your tea as you like. I personally really dislike honey in tea.

1. https://en.wikipedia.org/wiki/Honey

2. https://pdb101.rcsb.org/motm/77

3. http://www.jbc.org/content/278/27/24324.full "The midpoint for thermal inactivation of residual activity and the dissociation of FAD was 59 °C"

[adrianN]

If you put honey on a wound its osmotic properties alone have some antibacterial effect.