20 Million Tons of Food Thrown Away in UK

I have been writing on the issue of the so called food shortage facing the world, but I still find it very difficult to comprehend why this is so?
I find it difficult in understanding the scarcity of food when we read that the UK thrown away all this unwanted food, that mounted up is enough to feed Africa.
A staggering 4.4 million tons of food is thrown away by people in the UK.

So I don't know where these rumours are coming from that the world faces a food shortage. Perhaps the poor countries do as they always have, but I cannot see evidence in the UK or the US