The world is no stranger to the impact of climate change on food systems. A warmer world will see a smaller amount of land suitable for coffee-growing, while drought and extreme heat, exacerbated by climate change, have already slashed cereal production globally by 10 per cent over the last 50 years. The Philippines’ Department of Agriculture has estimated that recent superstorm Mangkhut may have damaged some 1.22 million hectares of rice and corn.
But higher levels of carbon dioxide in the atmosphere are bringing a quieter, invisible threat: an increasing number of studies show that food crops are less nutritious when they grow under conditions brought about by climate change.
Staple crops like rice, wheat and legumes have shown declines in nutrients essential to the body such as vitamin A, vitamin B, iron, zinc, and protein when grown in under 550 parts per million (ppm) of carbon dioxide, which is the level of CO2 emissions scientists expect the world to hit by as soon as 2050, based on current emissions rates.
The world crossed the 400ppm threshold in 2016.
A study by Harvard University published in August found that many food crops grown in simulated conditions for 2050 saw reductions in protein, iron and zinc levels by between 3 and 17 per cent compared to current levels. That means that people would receive fewer nutrients from the food they eat, which could lead to malnutrition, it said.
People don’t hunger for iron or zinc in the same way as calories, meaning this will be a hidden problem, but one with large public health consequences.
Dr Matt Smith, research fellow, T. H. Chan School of Public Health
More than two billion people are currently deficient in one or more nutrients in both developed and developing countries. Low income consumers may find it a struggle to put nutritious food on the table, while changing dietary habits means that more people are eating food that may be high in calories but low in nutrients, says Akmal Siddiq, director, environment, natural resources, and agricultural division, Asian Development Bank (ADB).
This could exacerabate the ongoing “double burden” of malnutrition in developing countries, like in the Philippines where obesity is rising in spite of a decline in food intake.
Without action, researchers expect another 175 million people to become zinc deficient, and 122 million more people to have a shortfall in protein intake by 2050.
This would be a blow for climate justice. The poorest regions of the world—South Asia, Southeast Asia, sub-Saharan Africa, North Africa and the Middle East—will bear the brunt of the impact. Countries in South and Southeast Asia are already some of the most vulnerable to changing weather patterns and intensified natural disasters, and have historically contributed the least to climate change.
The Harvard study found that, if things don’t change, India would be the most affected by the nutrition timebomb—50 million more people will be zinc deficient, 38 million will fail to meet their protein requirements, and 502 million women of childbearing age, and children under five years of age would be affected by iron deficiency. Zinc helps children fight off illness and is a determinant in child mortality, while iron is needed for the formation of red blood cells and tissue functions.
Malnutrition perpetuates the cycle of poverty, and can cost the global economy as much as US$3.5 trillion annually, says Anthony Hehir, global director of DSM Nutrition Improvement. This happens in three ways: malnutrition compromises work because the hungry individual is more likely to fall ill and suffer from poor physical development; it affects school performance for children and mental development, and a lack of good nutrition is correlated to the need for more health care, Hehir explains.
Although hunger is still a bigger problem numbers wise—800 million people go to bed hungry every night in the world—the danger of a ‘nutrient collapse’ is that it flies under the radar even by those suffering from it.
Dr Matt Smith, research fellow at Harvard T.H. Chan School of Public Health and a co-author of the Harvard study, tells Eco-Business that even if people continue to eat as they do now, the lower level of nutrition in food means millions could become newly deficient without knowing.
“People don’t hunger for iron or zinc in the same way as calories, meaning this will be a hidden problem, but one with large public health consequences,” says Smith.
Fighting the enemy we cannot see
Despite the potential scale of the problem, ADB’s Siddiq isn’t too concerned. “Vitamin and mineral deficiencies in food is nothing new,” remarks Siddiq.
A study in 2004 found that fruit and vegetables have lower protein, calcium, iron and Vitamin C levels compared to the 1950s, though its authors concluded this was a result of the food industry prioritising crop varieties with higher yields over better nutrition.
Secondly, these deficiencies can be effectively and affordably addressed through food fortification, a process through which vitamins and minerals can be added to food, he says. “Governments should make clear policy and laws to say that certain types of food should be fortified. The private sector should comply, and governments need to have labs and inspectors to ensure they comply.”
But despite countries such as Indonesia and India already mandating food fortification, malnutrition still persists—why?
Governments tend to act only when there is a crisis, Siddiq says. “It’s a quiet sort of crisis. And it’s human nature—unless there’s a huge hurricane or earthquake, governments don’t take action.”
But Smith says businesses can help in several ways. “Food companies could adopt voluntary guidelines on the fortification of grains to increase nutrient intake. Agricultural technology companies could begin breeding for crops that lose fewer nutrients under higher CO2 levels, or have higher nutritional content overall.”
And it is an attractive business case for food companies. Hehir points out that the business case for investing in nutrition and better food systems is substantial at US$18 for every dollar invested.
The Washington-based research centre International Food Policy Research Institute and its biofortification arm HarvestPlus have been working to develop crop varieties that are more immune to higher CO2 levels, says Smith.
Asked if supplements, found on pharmacy shelves, could reduce the impact of the nutrition collapse in food, Smith replies that supplements are not a long-term solution. “Not only are they logistically difficult to distribute to those most in need, they would need to be delivered in perpetuity, and do not address the underlying causes of dietary insufficiency.”
Supply chain issues are more dire than the crisis outlined in the Harvard study, says Siddiq. The lack of infrastructure for safe and efficient food transport in agricultural nations—which tend to be developing countries most at risk of nutrition deficiencies—means post-harvest food waste is high, with food thrown away because of spoilage and for cosmetic reasons, driving up food prices for consumers and eating into farmers’ revenues, he explains.
“Producers lose out, consumers lose out, and poor people spend 50 to 60 per cent of their incomes on food alone. If prices were 25 to 30 per cent lower, the poor would be able to eat good quality food,” he says.
Similarly, Smith adds: “Addressing supply chain inefficiencies could lower prices of many foods otherwise out of reach for at-risk groups, increasing dietary diversity and potentially insulating against the effects [of increased CO2 on plant nutrition].”
DSM’s Hehir believes collaboration is key to ensuring good nutrition for all, even in the face of climate challenges. “[The findings] are a call to action for companies to collaborate and develop innovative, sustainable and scaleable solutions to address climate change, resource scarcity and malnutrition.”
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