You might have noticed that the cost of food has gone up. In fact the price of wheat, rice and maize has nearly doubled in the past year.
It's thought that right now, 850 million people - that's more than 10 times the population of the UK - are short of food because it's too expensive or there's not enough of it.
Why's this happening?
The price of basic food such as wheat, corn and soya has stayed the same for quite a long time, about 30 years.
But as the world's population is getting bigger there's more pressure to feed more people, plus there's less land and water to go round.
Another reason is climate change. Droughts and floods make it hard to grow crops like rice and grain.
The price of oil has shot up and that makes it more expensive for farmers to run their tractors and to transport the food they make.
And lots of fields are being used to grow crops to make other stuff that can't be eaten - which is bad news for hungry people.
Who is this affecting?
The main losers are poor people who live in cities in poor countries, who are facing higher prices for food on low wages.
Some people are doing well out of the food crisis though. Farmers in rich countries like the US, Brazil, Argentina, Canada and Australia - and some in poor countries - are getting record prices for their harvests.
What can be done about it?
World leaders are meeting in the Italian capital Rome to talk about the problem of rising food prices.
Some countries are helping out with the cost of foods and international aid agencies have called for more money for food production in poor countries.