Billions more investment is needed in agriculture and food distribution systems around the world in the next few years, if widespread hunger is to be avoided, according to a group of leading scientists.

If that investment is directed towards sustainable forms of agriculture, then farming can also be made into a weapon in the fight against dangerous global warming, they said, as more environmentally friendly farming methods can result in soils absorbing carbon dioxide rather than releasing it.

Agriculture has been neglected in international climate change negotiations, but if governments persist in ignoring the problem then millions are likely to go hungry, according to a new report published on Wednesday morning, before the next round of negotiations in South Africa later this month.

"If you intensify agriculture to produce more food while producing less [greenhouse gas emissions] then you deliver benefits in terms of climate change as well – reducing emissions and increasing food security in vulnerable regions," said Sir John Beddington, the UK's chief scientist and one of the authors of the report, Achieving food security in the face of climate change, published by the Commission on Sustainable Agriculture and Climate Change, convened by the Consultative Group on International Agricultural Research.

Sir John added: "We need a socially equitable and global approach to produce the funding and policy initiatives that will deliver nutrition, income and climate benefits for all."

Investment should be targeted at the regions most vulnerable to climate change, as they are also the areas at greatest risk of food insecurity, the scientists said.

Another vital factor in improving food security is to reduce waste and improve food distribution systems. As much as half of the food produced is wasted before it reaches market in some developing countries, because of a lack of infrastructure such as refrigeration systems and reliable transport networks.

Waste is a problem not confined to the developing world, however – cheap food in the developed world has led to a culture of waste that means billions of tonnes of perfectly edible products are thrown away each year. The UK's Waste Resources Action Programme said this week there had been a sharp fall in household food waste, by 13% in the past year. But waste remains a serious problem – in the UK alone, at least £12bn worth of food is thrown away each year. Campaigners are preparing for an event in London on Friday to "feed the 5,000", using misshapen vegetables rejected by retailers to illustrate the enormous waste of edible food that takes place in the UK each day.

The scientists also called for a change in consumption patterns "to ensure that basic nutritional needs are met and to foster healthy and sustainable eating habits worldwide". An increasing amount of food production is geared towards feeding livestock, as people like to eat more meat as they grow more affluent.

The scientists also called for governments to create "comprehensive, shared, integrated information systems" on agriculture. But they said that the demands of an increasing global population for more food could be met without environmental harm, if farming methods were reformed and farmers educated in sustainable techniques.

Agriculture is likely to play only a minor role at Durban, where the next round of international climate change negotiations start at the end of November. Countries are hoping to sort out some of the details of a new agreement on climate change, such as how to ensure a flow of public and private sector finance from rich to poor countries, to help them cut greenhouse gas emissions and tackle the effects of climate change.