So, if you've ever snapped at a co-worker during an afternoon slump, or even forgotten to say your please and thank yous to the everyday heroes that make your morning coffee – there's a high possibility you were feeling hangry.
A dangerous combination of hungry and angry for anyone who doesn't know.
And while it's an emotion most of us will experience at some point (or you know, on a daily basis, whatever), there has never been any scientific evidence to back up this old wive's tale.
That is, until now.
According to New Scientist, there is actually a link between blood sugar levels and hormones that trigger aggression and anger.
Simply put – when your blood sugar is low, your rage is high.
As scientist and columnist Simon Oxenham discovered, low levels of blood sugar prompt the body to release cortisol and adrenaline, two chemicals associated with higher levels of stress.
Combine that with a spike in neuropeptide Y levels, a hormone that has been linked to aggression, and what have you got?
A recipe for disaster, that's what.
And this isn't the first time Simon has tested his theory.
In a 2014 study, the scientist asked a number of married couples to “stick pins into voodoo dolls that represented their loved ones, to reflect how angry they felt towards them.”
Results showed that participants inserted more pins into the voodoo dolls when their blood sugar levels were low.
So, even though the method of testing was albeit, a little creepy – at least there's an actual reason for those pre-lunch blues.