Over 4 billion people may be overweight by 2050 globally, while 500 million will be underweight, study says
Dietary patterns are shifting worldwide and yet, not synchronous – from scarce, plant-based diets with fresh and unprocessed foods to diets high in sugar, fat and animal-source foods, featuring highly-processed food products – global diet trends are constantly evolving. Analyzing the consequence of this “nutrition transition”, researchers have made a startling projection: By 2050, more than 4 billion people could be overweight, 1.5 billion of them obese, while 500 million people continue to be underweight if the current trends continue.
The analysis by Potsdam Institute for Climate Impact Research (PIK) forecasts that overweight and obesity could increase from 1,993 million (29%) in 2010 to 4,135 million (45%) in 2050 and 5,018 million (56%) in 2100. Similarly, the number of obese people could spike from 636 million (9%) in 2010 to 1,493 million (16%) in 2050, and 2,052 million (23%) in 2100. It also projects that if current trends continue, global food demand will increase by about 50% between 2010 and 2050, the demand for animal products like meat and milk will approximately double, a development that requires more and more land.
According to experts, undernutrition, overnutrition, and food-related environmental pollution co-exist in all world regions. They are affected by common drivers and require common solutions, but have too long been analyzed in academic silos. Consumer behavior, including poor dietary choice and food wasting behavior, is central to all three problems, and any policy designed to bring about behavioral change in these areas has to be carefully evaluated against trade-offs and synergies, suggests the team.
“While today, many countries are still struggling with undernourishment, we see even in lower-middle-income countries a strong rise in overweight and obesity within the same population. Given the trends that we observe from all around the world, we can expect that the same countries that currently face underweight will be faced with overweight and obesity at an epidemic scale in a few decades. Policymakers should plan ahead and find solutions that address both undernutrition and overnutrition at the same time, for example, by expanding horticultural production and increasing the consumption of healthy vegetables and fruits,” lead author Benjamin Bodirsky from PIK told MEA WorldWide (MEAWW).
Bodirsky warns that if the observed nutrition transition continues, countries will not achieve the United Nations goal of eradicating hunger worldwide. “At the same time, our future will be characterized by overweight and obesity of mind-blowing magnitude. By 2050, 45% of the world’s population could be overweight and 16% obese compared to about 29% and 9% in 2010 respectively. This development is due to the insufficient global distribution of food as well as due to the shift from scarcely processed plant-based diets towards unbalanced, affluent diets, where animal protein, sugar, and fat displace whole grains and pulses,” he explains.
The expert further cautions that the increasing waste of food and the rising consumption of animal protein imply that the environmental impact of the agricultural system will “spiral out of control. “Whether greenhouse gases, nitrogen pollution, or deforestation, we are pushing the limits of our planet -- and exceed them,” adds Bodirsky.
The modeling study, published in Scientific Reports, provides a consistent and long-term overview of a continued global nutrition transition from 1965 to 2100. It uses an open-source model that forecasts how much of food demand can be attributed to factors like population growth, aging, increasing height, growing body mass index, declining physical activity, and increasing food waste. The results show that the nutrition transition is an ongoing and unchecked global process.
“There is enough food in the world, (but) the problem is that the poorest people on our planet have simply not the income to purchase it. And in rich countries, people don’t feel the economic and environmental consequences of wasting food. But redistribution alone would not be sufficient, as actually both the poor and the rich eat poorly; there is a lack of knowledge about a healthy way of life and nutrition,” explains co-author Prajal Pradhan from PIK.
What can be done?
The team says that going beyond the global database, national assessments are urgently needed, and could include more detailed statistics and scenarios, or explore policy interventions that are tailored to the local context. Policy action focused on consumption behavior should “holistically target” all forms of malnutrition as well as environmental impacts, as there are synergies and trade-offs, most importantly in respect to animal-source foods and food waste, they emphasize.
“Our empirical analysis substantiates that current food policy has not managed to achieve a paradigm change of the nutrition transition. So far, no country can serve as an example of a successful policy-induced reduction of obesity, animal-source foods, or food waste. There is no evidence that individual decisions or private sector action will suffice. Instead, policy leadership is required, implementing a combination of multiple integrated policy instruments,” the authors recommend.
Discussed policy measures in the report include marketing restrictions for unhealthy and polluting food items, nutrition education such as cooking classes or school gardens, public provision of healthy and sustainable food in canteens, raising public awareness, obligatory food labeling, and regulatory policies such as the ban of trans-fatty acids.
“Unhealthy diets are the world’s largest health risks. We urgently need political measures to create an environment that promotes healthy eating habits. This could include binding regulations that limit the marketing of unhealthy snacks and promote sustainable and healthy meals in schools, hospitals, and canteens. A stronger focus on nutrition education is also key, from early education in kindergarten to counseling by medical doctors and nurses. What we eat is of vital importance, both for our own health and that of our planet,” concludes co-author Sabine Gabrysch, head of PIK’s research department on climate resilience.