Make a shopping list and buy \"funny fruit\" to cut food waste and help the world \"shape a sustainable future,\" two UN agencies urged on Tuesday. The United Nations Environment Programme (UNEP), Food and Agriculture Organzation (FAO) and partners unveiled a campaign dubbed \"Think-Eat-Save Reduce Your Foodprint\" to change global practices that result in the loss of 1.3 billion tonnes of food each year. The programme is aimed primarily at consumers, food retailers and the hotel and restaurant industry, and is based on three recommended actions: think, eat, and save. \"In a world of seven billion people, set to grow to nine billion by 2050, wasting food makes no sense - economically, environmentally and ethically,\" a statement quoted UN Under-Secretary-General and UNEP Executive Director Achim Steiner as saying. \"We\'re doing something that is completely irrational,\" he lamented to reporters in Geneva, before adding that he hoped the campaign would \"literally mobilise tens of millions of people to become part of the solution.\" FAO Director General Jose Graziano da Silva pointed out that in industrialised nations, around 300 million tonnes of food are wasted each year, \"because producers, retailers and consumers discard food that is still fit for consumption.\" That is more food than is produced in sub-Saharan Africa, and is enough to feed the estimated 830 million people who now go hungry worldwide, he added. The programme estimates the overall cost of wasted food at about $1.0 trillion (751 billion euros) per year, with most losses occurring in production stages -- such as harvesting and distribution -- and blamed on problems from storing food in difficult climatic conditions to unreliable harvests. It is retailers and consumers, whoever, who are usually guilty of wasting food. Consumers can participate in a global effort by respecting a few simple recommendations, the UN agencies said. Planning meals, making shopping lists and avoiding impulse buying helps, as does staying alert \"to marketing tricks that lead you to buy more food than you need.\" Another good idea is to \"buy funny fruit\" or vegetables that would otherwise be thrown out because their size, shape or colour do not meet market standards. Tristram Stuart of the Feeding the 5,000 campaign told reporters in Geneva: \"Wonky fruit and vegetables are very often left on farms across Europe and North America simply because they don\'t meet the cosmetic standards of retailers, and they are left on fields to rot.\" People, he insisted, must \"adopt the value that food is simply too good to waste.\" Paying attention to expiry dates and \"zeroing down your fridge\" with recipes that use up food set to go bad helps, the UN agencies said, as does freezing food, asking restaurants for smaller portions, eating leftovers, composting food or donating it to food banks, soup kitchens and shelters. Retailers can offer discounts for food that is nearing its sell-by date, standardise labels and donate more food. Restaurants were urged to \"limit menu choices and introduce flexible portioning,\" to audit how much food they waste, and to set up \"staff engagement programmes.\" Finally, an Internet site, thinkeatsave.org is to serve as a global platform for sharing information on other initiatives that people come up with. For the campaign to work, everyone has to get involved -- families, supermarkets, hotel chains, schools, sports and social clubs, company CEOs, city mayors, and national and world leaders, the Rome-based FAO said. According to the Britain-based not-for-profit organisation WRAP (Waste & Resources Action Programme), which is offering its expertise to the FAO for the campaign, the average British family could save £680 ($1,090, 815 euros) per year by tackling food waste. Throwing away good food wastes the land, water, fertilizers and efforts used to grow it, Steiner said, while the transport involved generates excess greenhouse gases. European Commissioner for Environment Janez Potocnik told reporters via videolink that he was \"delighted\" with the campaign against food waste. Food production and consumption \"must be one of the most inefficient uses of global resources,\" Potocnik said, insisting: \"We must stop taking our resources for granted before it is simply too late.\"