Warning: Contains a dangerously high number of Game of Thrones spoilers.

It may not be as glamorous as White Walkers or dragons, but there's one Game of Thrones threat we badly need to discuss: food.

Or rather, the lack of it.

With some minor ship-based exceptions, Game of Thrones — despite its fantasy elements — has always been a fairly realistic show.

The battle tactics, the politics, the psychologies of various characters — for the most part, it all rings true.

The need to build up food stocks ahead of winter hasn't been a main theme in recent episodes — there's too much other stuff going on — but it is a recurring one. And with winter now upon us, it's going to be crucial in the coming episodes.

Food and siege warfare

Image: hbo/mashable composite

Bronn said it best back in Season 2.

In a scene where he explains to Tyrion and Varys his reasons for rounding up the thieves in King's Landing, everyone's favourite mercenary touches on something that's soon going to be a huge problem throughout Westeros.

"Have you ever been in a city under siege?" asks Bronn. "Maybe this part's not in your books. See, it's not the fighting that kills most people — it's the starving.

"Food's worth more than gold."

Obviously he's not talking about winter there, but the rule still applies: in any situation where it's difficult (or impossible) to leave the castle walls, food becomes a crucial resource.

And it's one thing nobody in the Seven Kingdoms has enough of.

Food in the North

Image: hbo/mashable composite

Sansa is perhaps the only person at the moment who seems to realise just how damn important an adequate food stock will be when the snow rolls in.

Here's a snatch of dialogue she exchanges with Winterfell's Maester Wolkan back in Episode 3:

Sansa: How much do we have?

Maester: 4000 bushels, m'lady.

S: What does that mean?

M: For the current occupants of the castle, it's enough food for a year. Perhaps more.

S: And what's the longest winter in the past 100 years?

M: I'm not entirely certain, I'll check Maester Lewin's records. He kept a copy of every raven scroll.

S: You're telling me we don't have enough food. Especially not if the armies of the North come back to defend Winterfell.

M: No, my lady. Most likely not.

S: Well we must prepare for that eventuality. Whatever direction the threat comes from, this is the best place to be. We need to start building up our grain stores with regular shipments from every keep in the North. If we don't use it by Winter's end we'll give it back to them, but if the entire North has to flee to Winterfell they won't have time to bring wagon loads of grain with them.

It's no exaggeration to say that Sansa may have saved hundreds (or even thousands) of lives in that scene.

The thing is — if you believe the legends Old Nan used to tell Bran — the longest Winter (cheerfully called the "Long Night") lasted a full generation.

"Kings froze to death in their castles, same as the shepherds in their huts," says Old Nan back in Season 1. "And women smothered their babies rather than see them starve."

Doesn't sound great, does it?

Obviously the Long Night is the stuff of legends. We don't know how true it is. But we do know that the White Walkers exist, and the Long Night was meant to be the last time they paid a visit.

Maybe the fact that they're about to visit again could be a sign of another long winter.

One thing's for sure: Winterfell is going to need a hell of a lot more food if winter lasts a whole generation this time around.

And the Northerners aren't even the ones in the biggest trouble...

Cersei now has no food

Image: hbo/mashable composite

Cersei was pretty much screwed the minute Daenerys set sail for Dragonstone, but now she's really screwed.

Forget the fact she's allied with Euron and they've managed to get a couple of minor victories over Daenerys. It won't make a difference.

Now that Daenerys has torched the bulk of the food supplies the Lannisters were bringing into King's Landing, Cersei is in real trouble.

On the one hand, she's got a potential siege situation — as outlined earlier by Bronn — to contend with. If Dany takes Tyrion's advice to blockade King's Landing, Cersei doesn't even have the basic supplies needed to help her people survive.

And on the other hand, Winter is coming. If the cold reaches far enough South (which it almost certainly will), there's going to be no more food left to harvest. Even if Cersei somehow manages to fend off Daenerys, the people of King's Landing simply won't have enough to eat.

Ultimately, this is Daenerys' problem too: if Cersei surrenders and she takes over the Iron Throne, she's going to have to find a way to replace the supplies she just burned down.

Rival armies, White Walkers, dragons — none of it matters that much at the end of the day.

The greatest threat is starvation.