Why the world needs a new diet

What we eat determines our health. It also decides the health of our planet. In the newly proposed Dietary Guidelines, the US is finally moving towards acknowledging the fundamental connections between human and planetary health. The improved diets suggested in the guidelines, offers the US a major opportunity to position itself as a global frontrunner in tackling both the public health and environmental challenges of today.

Every five years the federal government issues advice on what constitutes a healthy diet, through by the Dietary Guidelines Advisory Committee (DGAC). The newly proposed Dietary Guidelines for the first time recognizes the unequivocal connections between the health of humans and the planet. The US government is yet to decide whether to adopt the recommendations – a process which has been rendered all the more tenuous by the outcry of the meat industry.

The controversy surrounds the DGAC’s assessment that a diet higher in plant-based foods and lower in animal-based foods could significantly reduce the environmental impacts of the US food and agriculture sector, and thereby ensuring access to sufficient, nutritious and safe food for both the current population and future generations. We find this controversy very regrettable, as the DGAC conclusion is backed by the mandated panel of experts’ broad range of consultations and robust body of scientific literature.

Food systems, both in the US and globally, currently operate in ways that are unsustainable both for human and planetary health. While food is one of the most vital human needs, food production is also one of the most resource demanding human activities. Agriculture is responsible for up to 30% of global greenhouse gas emissions, with 14.5% of global emissions caused by livestock production alone. In general, one calorie of animal protein requires more than 11 times as much fossil energy input as producing one calorie of plant protein.

This has, for instance, led the European Union to adjust its dietary recommendations – through its Roadmap to a Resource Efficient Europe – to less animal-based and more plant-based foods. The time has come for the US to do the same. Today, there is enough scientific evidence in support of benefits for human health of adopting a sustainable low-animal protein, plant-based diet for such an integration to be part of modern dietary guidelines. Not acknowledging this would be to deny the most recent science.

With current trends in population growth and changing dietary preferences following economic development, an estimated 50-70% more food must be produced by 2050 to meet the demands of a larger and wealthier world population estimated to reach 9-10 billion. With unsustainable diets kept unabated, this would likely result in the emissions from food systems alone pushing the world across the critical threshold of 2°C globalwarming.

Further, agriculture is responsible for 70% of total freshwater withdrawals, which mainly goes to irrigating fields. Agriculture is the prime cause of loss of species and main source of nutrient overload in aquatic and marine systems and a large chemical polluter. It has expanded like no other human land use at the expense of biodiverse and carbon storing forests, today covering a quarter of ice-free land on Earth and accounting for 80% of all deforestation.

Primary food production is thus an essential sector to address in order to achieve overall environmental sustainability. Equally, environmental sustainability is a fundamental determinant of the outcome of food production: a deteriorated resource base will inevitably undermine landscape productivity, and consequently have severe repercussions on human health and food security.

The current diets of Americans have a huge potential for improvement, with a high consumption of highly processed and animal-based foods at the expense of plant-based foods. The average American consumes 45% more meat per week than is recommended by the US Department of Agriculture. Together with an average decrease in physical activity, diets play a major role in the current national public health crisis. Today, about two-thirds of all adults and one third of children and adolescents in the US are overweight or obese. Roughly half of the adult population is suffering from at least one preventable disease, including cardiovascular disease, type 2 diabetes and various forms of cancer. For example, it has been shown that 12% colorectal cancers would be preventable by avoiding the consumption of processed meat alone. In addition, recent research has suggested that plant-based diets have the potential of halving the climate footprint of the typical US or UK diets.This clearly demonstrates a need to shift towards less and better-quality meat.

As noted by the DGAC, the situation is forcing the US health care system to focus on treatment rather than prevention. Incentivizing healthy and sustainable diets can yield major savings in currently rocketing public health expenditure. Further, no country has so far managed to curb the obesity epidemic – the US is in a strong position to be the first country to achieve this reversal. The DGAC also stresses that meeting future food needs will hinge on changing the way people eat and on developing food production practices that reduce environmental impacts and conserve resources.

The global food system of today does not deliver healthy, equitable and affordable nutrition for all. The double burden of malnutrition remains persistent: while almost 850 million people go hungry, more than 2 billion are overweight or obese. Combining the burdens of hunger, micronutrient deficiencies and obesity, as much as half the global population can be classified as malnourished. It is widely accepted that this will demand major dietary shifts, with a special emphasis on less meat in high-income countries like the US. In a world of 9-10 billion people in 2050, it is also important to provide the ‘ecological space’ allowing populations in low and middle income countries to increase their per capita consumption of animal proteins for micronutrient adequacy.

The American meat industry has opposed the proposed Dietary Guidelines. The industry says the panel has strayed too far from its mission. The North American Meat Institute has called the recommendations “flawed” and “nonsensical”, and pinpointed that the DGAC has failed to note the importance of “nutrient-dense” lean meats in a healthy diet. However, the social and economic risks associated with unsustainable meat production cannot be overlooked. The meat industry, on the other end, is being accused of neglecting its environmental impacts, in part because of the perceived threat to its production volumes and economic viability. However, a stronger focus on meat quality and sustainable livestock systems might bring about new business opportunities. Therefore, the enactment of the dietary guidelines as currently proposed, is not threatening the survival of the meat industry; rather, the meat industry needs to reinvent itself by focusing on selling quality rather than volume.

A public hearing process is currently underway, ending on May 8, before the final US Dietary Guidelines will be adopted and issued later in the year. We call for strong political decisiveness and a final decision that is rooted in strong, evidence-based science. The new Dietary Guidelines provide a historic moment to set a combined agenda linking food, health and sustainability, with potential global repercussions.

In an interview with The Wall Street Journal March 4, Agriculture Secretary Tom Vilsack suggested that sustainability issues fall outside the scope of the dietary guidelines the way the system is set up today. And the same time he pointed out that sustainable diets are “an appropriate debate to have” and could not rule out the possibility that sustainability will play a role in the dietary guidelines.

Let’s not miss out on the opportunity to have such a debate. And let us make sure that the political arguments are explored and the scientific knowledge behind the committee’s proposal is examined. Our opinion is clear, the time to make the link between human and planetary health is now.

Although a few countries such as Sweden, Brazil, the Netherlands and Qatar have already made steps in developing such integrated guidelines, there is a huge opportunity for the US to take lead internationally in being one of the first nations to have a clear integration of environmental sustainability in its nutritional guidelines.

As the global population grows and human pressures on Earth’s resource rise, we are rapidly shifting from a ‘small world, big planet’ towards a ‘big world, small planet’ paradigm. This means we need to safeguard the very life supporting systems that are paramount for our food production by reducing the environmental footprint of our diets.

The US has long been a guiding star for international social development. As a global trendsetter and the largest economy in the world, the US not only possesses a major opportunity, but also a major responsibility, in paving the way towards better diets. In the future, the American dream of big cars and burgers will need to be adjusted to more active transport and sustainable, healthy eating. Better is the new bigger. The world needs a new diet. And it is waiting for the US to take the lead.

This article is published in collaboration with The Huffington Post. Publication does not imply endorsement of views by the World Economic Forum.

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Author: Johan Rockström is Director of the Stockholm Resilience Centre at Stockholm University. Walter Willett, M.D., DrPH, MPH is Chairman, Professor of Epidemiology and Nutrition, Department of Nutrition — Harvard School of Public Health. Gunhild A. Stordalen Headshot is MD/PhD, Chair of Stordalen Foundation, GreeNudge and EAT Initiative/EAT Stockholm.

Image: Cows look on during feeding at the livestock breeding complex and collective farm. REUTERS/Eduard Korniyenko