Over the last decade, milk has become a bit controversial.
Some people say it's a necessary and nutritious food, vital for healthy bones, but others say it can cause cancer and lead to an early death.
So, who's right?
And why are we drinking it anyway?
Milk is the basis of every mammal's diet after birth, when our digestive systems are immature and small.
Basically, it's power food to kick-start our bodies and help us grow.
Milk is rich in fat, vitamins, minerals, and milk-sugar: lactose.
On top of that, for a while after birth, it also contains antibodies and proteins that protect us from infections and regulate our immune system.
But it's a lot of effort for mothers to produce.
Eventually, humans stop drinking mother's milk and transition to the diet of their parents.
