The "planetary health diet" is based on cutting red meat and sugar consumption in half and upping intake of fruits, vegetables and nuts.
And it can prevent up to 11.6 million premature deaths without harming the planet, says the report published Wednesday in medical journal The Lancet.
The authors warn that a global change in diet and food production is needed as 3 billion people across the world are malnourished – including those who are under and overnourished – and food production is overstepping environmental targets, driving climate change, biodiversity loss and pollution
The world's population is set to reach 1
"The stakes are very high," Dr. Richard Horton, editor-in-chief at The Lancet, said of the report's findings, noting that 1 billion people live in hunger, and 2 billion people eat too much of the wrong foods
Horton believes that " "
" Using the best available evidence "of controlled feeding studies, randomized trials and large cohort studies, the authors came up with a new recommendation , explained Dr. Walter Willett, lead author of the paper and professor of epidemiology and nutrition at Harvard T.H. Chan School of Public Health
The report suggests five strategies to ensure that people can change their diets and not harm the planet by doing so: stimulating people to eat healthier, shifting global production to varied crops, intensifying agriculture sustainably, stricter rules around
The 'planetary health diet'
To enable a healthy global population, the team of scientists created a global reference diet, which they call the "planetary health diet" "which is an ideal daily meal plan for people over the age of 2, that they will help reduce chronic diseases such as coronary heart disease, stroke and diabetes, as well as environmental degradation
The diet breaks down the optimal daily intake of whole grains, starchy vegetables, fruit, dairy, protein, fats and sugars, representing a daily total intake of 2500 calories.
They recognize the difficulty of the task, whic h will need "substantial" dietary shifts on a global level, requiring the consumption of foods such as red meat and sugar to decrease by more than 50% In turn, consumption of nuts, fruits, vegetables and legumes must increase more than two-fold, the report says.
The diet advises people to consume 2,500 calories per day, which is slightly more than what people are eating today, said Willett. People should eat a variety of plant-based foods, low amounts of animal-based foods, rather than saturated fats, and few refined grains, highly processed foods and added sugars, "he said.
Regional differences are also important to note. For example, countries in North America eat about 6.5 times the recommended amount of red meat, while countries in South Asia eat 1.5 times the required amount of starchy vegetables
"Almost all the regions in the world are over quite substantial" the recommended levels of red meat, Willett said.
The health and environmental benefits of dietary changes like these are known, "but until now the challenge of achieving healthy diets from a sustainable food system has been hampered by a lack of science-based guidelines," said Howard Frumkin, Head of the UK biomedical research charity The Wellcome Trust has funded research
"It provides governments, producers and individuals with an evidence-based starting point to work together to transform our food systems and cultures, "
If the new diet were adopted globally, 10.9 to 11.6 million premature deaths could be avoided every year – equating to 19% to 23.6% of adult deaths.
Making it happen
Some scientists are skeptical of whether shifting the world's population
The recommended diet is "quite a shock," in terms of how feasible it is and how it should be implemented, said Alan Dangour, Professor of Food and Nutrition for Global Health at London School of Hygiene and Tropical Medicine. "What makes the implementation quite difficult is the fact that cross-government departments need to work together," he said.
At the current level of food production, the reference diet is not achievable, said Modi Mwatsama, senior science leader (food systems, nutrition and health) at the Wellcome Trust. Some countries are not able to grow enough food because they could be, for example, lacking resilient crops, while in other countries, unhealthy foods are heavily promoted, she said.
Mwatsama added that unless there are structural changes, such as subsidies that move away from meat production, and environmental changes, such as limits on how much fertilizer can be used, "we will not see people meeting this target."
strategies, of which subsidies are one option. These include a recommendation to ensure good governance of land and ocean systems, for example by prohibiting land clearing and removing subsidies to world fisheries, as they lead to overcapacity of the global fishing fleet.
Secondly, the report further outlines strategies such as incentives for farmers to shift food production away from large quantities of a few crops to various production of nutritious crops.
Healthy food must also be made more accessible, for example low-income groups should be helped with social protection to avoid continued poor nutrition, the authors suggest, and people encouraged to eat healthily through information campaigns.
A fourth strategy suggests that when agriculture is intensified, it should take local conditions into account to ensure the best agricultural practices for a region, in turn producing the best crops.
Louise Manning, professor of agro-food and supply chain resilience at the Royal Agricultural University, said meeting food waste reduction target is a "very difficult thing to achieve" because it would require governments, communities and individual households to come together. However, "it can be done," said Manning, who was not involved in the report, noting the rollback in plastic use in countries such as the UK
The planet's health
The 2015 Paris Climate Agreement aimed at limiting global warming to 2 degrees Celsius above pre-industrial levels. Meeting this goal is not just about carbonizing energy systems by reducing fossil fuels, it's also about a food transition, said Johan Rockström, professor of environmental science at Stockholm Resilience Center, Stockholm University, Sweden, who co-led the study.
"This is urgent," he said. Without a global adaptation of the reference diet, the world will not succeed with the Paris Climate Agreement. "
A sustainable food production system requires non-greenhouse gas emissions such as methane and nitrous oxide to be limited, but methane is produced during digestion of livestock while nitrous oxides are released from cropland and pastures But the authors believe these emissions are unavoidable to provide healthy food for 10 billion people. They emphasize that the decarbonisation of the world's energy system must progress faster than anticipated, to accommodate this.
Overall, ensuring a healthy population and planet requires combining all strategies, the report concludes – major dietary changes, improved food production and technology changes , as well as reduced food waste
"Designing and operationalizing sustainable food systems that can deliver healthy diets for a growing and wealthier world population," said Rockström, "the solutions do exist."
"It's about behavioral change. It's about technologies. It's about policies. It's about regulations. But we know how to do this. "
CNN's Meera Senthilingam contributed to this report