Now here's what I think is an interesting question. I don't believe neither Elder Scrolls nor D&D tell us, but what do Dragons eat?

Adventurers, cows, dragonborns?

So, they're carnivorous? Fully carnivorous, or do they also eat vegetation?

Do vegetarians count?

I think they dont need to eat, they do it for sport. so anything they think tastes good

1. They don't need to eat (ex: Paarthurnax)

2. It's not sport, it's domination.

Dragons eat whatever they damn well want!

Also, horses. Horses seem to get eaten a lot in books with dragons.
When Skyrim came out and we learned about how there would be random dragon attacks, I was thinking they would show dragons randomly carrying off horses to eat sometimes. That would have been fun.

Depends on the type of dragon we're talking about. Skyrim's dragons? D&D's dragons?

On the whole, dragons are carnivores (as indicated by their teeth) so I would suspect they'd need to eat large animals to keep their metabolism going. Small people just aren't going to cut it (no pun intended), they need something the size of a horse to a mammoth.

D&D dragons are primarily carnivores.

Elder Scrolls dragons are Aedra, they don't need to eat.

Judging by what I find inside dead dragons in Skyrim, they eat a lot of armor, weapons, gemstones and gold. Even wolves eat gemstones and jewelry, apparently.

I once looted daedric armor from a dragon.

Dragons do not eat Children, due to the indigestion. Anything else is Fair Game. Dragons prefer Armored Opponents because They are crunchy on the outside and soft and chewy on the inside.

The wolves don't eat jewels, they're worn by the people the wolf eats.

I've found jewelry inside mud crabs too. Do they eat a whole person?