import duties making the product less profitable?

We will not impose import duties on EU food.

A 44% increase in the price of very basic foodstuffs will push a few million people into malnutrition

That assumes we will levy EU Tariffs on it. We will not.

A 44% increase in food costs would be pretty disastrous for most people. And it isn't clear that we will be able to get the supplies.

It isn't clear where this extra cost will come from, and we will get the supplies from the current suppliers. Why would they stop?