Currently, the total world population of the world is 7.6 billion and increasing .
More than 50% of these people currently live in cities.
Total World Population is expected to rise to 9.6 billion by 2050. And at the same time, 66% of this number will reside in cities.  During then, the global food demand will increase by 59% to 98%. 
To put it into perspective, the total population residing in urban cities currently is 3.8 billion. And the total population who will reside in urban cities in 2050 will be 6.336 billion.
At the current rate of urbanization, over 2 million hectares of land are used every year; ¾ of them are agricultural land. 
Current methods of food production include urban agriculture. With this method, about 200 million urban farmers around the world supply food to over 700 million people. 
However, urban agriculture is associated with a high risk of contamination .
It is observed that in most developing countries, complex interrelations of activities in food supply and distribution are not understood in their urban planning consideration, resulting in poorly maintained markets and under-utilized new markets. 
Current methods of food production are severely polluting, inequitable, and unjustifiably wasteful . According to the three-year study commissioned by the UN and the world bank, the answer to the food sustainability is agroecology. However, there is little or no aid for the programme. Aid for agroecology is less than 5% of the total aid given to industrial agriculture .
The threat of climate change will also endanger the global food supply by suppressing growth in crop yields and affect food distribution chains .
In fact, the current food systems do not currently provide nutritious food in an environmentally sustainable way to the world’s population. To mitigate the problem, world leaders are meeting to ensure “food security, environmental sustainability, and economic opportunity” .
Then I heard what sounded like a voice among the four living creatures, saying, “Two pounds of wheat for a day’s wages, and six pounds of barley for a day’s wages, and do not damage the oil and the wine!”
(Revelations 6:6, NIV).
 – Current World Population. Retrieved from http://www.worldometers.info/world-population/
 – Future of Urban Development and Services. Retrieved from https://www.weforum.org/projects/future-of-urban-development-services
 – Feeding Urban Asia: New Approaches for Providing Safe, Nutritious and Affordable Food. Retrieved from https://www.ecosperity.sg/en/ideas/feeding-urban-asia-new-approaches-for-providing-safe-nutritious-and-affordable-food.html
 – Feeding an increasingly urban world. Retrieved from http://www.fao.org/worldfoodsummit/english/newsroom/focus/focus2.htm
 – Moeller, N., Pimbert, M. (2018). Why Food Production Needs to Change to Avoid a Crisis. Retrieved from https://www.independent.co.uk/life-style/food-and-drink/food-production-farming-agriculture-needs-change-avoid-crisis-population-nine-billion-2050-a8275646.html
 Johnston, I. (2017). World food supplies at risk as climate change threatens international trade, warn experts. Retrieved from https://www.independent.co.uk/news/world/world-food-supplies-climate-change-international-trade-global-warming-chatham-house-chokepoints-a7808221.html
 – New Vision for Agriculture. Retrieved from https://www.weforum.org/projects/new-vision-for-agriculture