Understanding human water turnover in times of water scarcity

This writing was originally published in Cell Metabolism in their February issue.

Water covers 70% of the planet; however, only 3% is freshwater, which the global population depends on to drink, irrigate crops, and for our sanitation and hygiene. Water is central to almost all human activity and endeavors and, most importantly, the homeostasis of our bodily functions and health. We know that access to both adequate quantity and quality of water drives optimal health. Still, when in shortage or contaminated, it can cause deleterious effects on various health outcomes, some more known than others (1).

While there is substantial research understanding the health effects of insufficient water intake, there are measurement uncertainties in how much water people consume, retain, and excrete as well as a paucity of evidence on the influence of physical, metabolic, and environmental factors on water homeostasis in the human body. A recent study by Yamada et al. published in Science provides further insight into the determinants of water turnover (WT) or the water processed and used by the body (2). The largest study of its kind, they sampled 5,604 people living across 23 countries across diverse regions of the world ranging from 8 days to 96 years old. They examined whether age, body composition, physical activity, socioeconomic status, and geographical attributes of various regions impacted WT. They did this by having subjects consume 100 ml of water, of which 5% was deuterated. This isotope tracking allowed the investigators to measure WT in a highly accurate and precise way.

Predictably, WT was highest in neonates and decreased with age, positively correlated with free mass, total energy expenditure, and physical activity, and negatively correlated with percent body fat. Interestingly, where people live, and their livelihoods matter for WT as well. WT was higher in those living in hotter and more humid places and higher altitude areas. People with traditional livelihoods, such as hunter-gatherers and subsistence farmers, had higher WT than those working outside agriculture. Furthermore, people living in countries characterized as having a low human development index (HDI)—a comprehensive composite index that measures the different dimensions of human development, including standards of living, life expectancy, and education—had higher WT than those living in countries with middle- and high HDI, even after adjusting for physiological and environmental factors.

While some of these results may not be surprising regarding age and biology, they present clear warning signs of vulnerability when considering looming global scenarios, trends, and shocks to water security, with poor populations disproportionately suffering the most severe consequences (3). The world is already grappling with water scarcity—the availability of water depends on an intimate dance between a region's water demand and water supply. As it stands, 4 billion people live with severe water scarcity at least one month a year, with nearly half of those people living in China and India. Half a billion live with severe water scarcity all year round (4). Distressing still, 784 million people worldwide lack access to safe drinking water (5). The figure below shows how these numbers break down by the four major country income groups, and climate change will likely worsen this situation.

Figure 1: Number of people (millions) without access to safe drinking water, 2020

Legend: Each bar represents the surface (drinking water directly from a river, dam, lake, pond, stream, canal, or irrigation canal), limited (drinking water from an improved source for which collection time exceeds 30 minutes for a roundtrip including queuing) and unimproved (drinking water from an unprotected dug well or unprotected spring) sources of drinking water by country income classification. Source: World Health Organization and UNICEF Joint Monitoring Programme, 2021

Climate change will have significant impacts on how much water is available as well as its quality. Already, water systems that provide freshwater to human populations are drying up and polluted from overuse and runoff, much of this coming from agriculture and other anthropogenic forces (6). Water ecosystems around the world will also continue to be strained and stressed. For example, since 1900, approximately 68% of wetlands have been lost, which are essential ecosystems that purify drinking water systems, among many other functions (7). In addition, extreme weather events related to climate change, such as changes to precipitation and severe drought, as well as the melting of glacier ice, is and will continue to impact water resources. There will also be a decline in the quality of water sources due to anthropogenic and natural factors, along with an increased demand for water due to higher temperatures and evaporation rates. As a result, water insecurity under "business as usual" climate scenarios will worsen (8).

Human demand for water worldwide has increased six-fold over the past century and continues to rise at around 1% per year due to the growing population and global economy (9). At the current consumption rate, by 2025, two-thirds of the world's population may face water shortages (10). What will be the consequences for those vulnerable populations living in countries of low HDI given their increased demand for water? Even a slight imbalance in the delicate homeostasis of WT could put these populations at disproportionate risk for various health disparities, along with constraints on access to improved water safety and quality.

We are just beginning to understand the importance of how water is cycled through the body and how to measure it. Yamada and colleagues shed further light on the factors influencing how water is used and excreted in the body. One gap they highlight is the inability to measure the influence of water coming from food on WT. For those who work in food security, it will be necessary to understand how the quality and diversity of diets contribute to and potentially further protect water homeostasis in distinct biological, sociodemographic, and geographical contexts. Understanding this relationship could spur joint policy action among communities concerned with food and water security. With climate disruption continuing to threaten the quantity and quality of food and water sources, scientific and geopolitical collaboration has never been more urgent.  

References

1.     Popkin, B.M., D’Anci, K.E., and Rosenberg, I.H. (2010). Water, hydration, and health. Nutr. Rev. 68, 439–458.

2.     Yamada, Y., Zhang, X., Henderson, M.E.T., Sagayama, H., Pontzer, H., Watanabe, D., Yoshida, T., Kimura, M., Ainslie, P.N., Andersen, L.F., et al. (2022). Variation in human water turnover associated with environmental and lifestyle factors. Science 378, 909–915.

3.     Dell’Angelo, J., Rulli, M.C., and D’Odorico, P. (2018). The global water grabbing syndrome. Ecol. Econ. 143, 276–285.

4.     Mekonnen, M.M., and Hoekstra, A.Y. (2016). Four billion people facing severe water scarcity. Sci. Adv. 2, e1500323.

5.     World Health Organization and UNICEF (2021). World Health Organization and UNICEF Joint Monitoring Programme. https://washdata.org/data/household#!/dashboard/new.

6.     van Vliet, M.T.H., Flörke, M., and Wada, Y. (2017). Quality matters for water scarcity. Nat. Geosci. 10, 800–802.

7.     Davidson, N.C. (2014). How much wetland has the world lost? Long-term and recent trends in global wetland area. Mar. Freshw. Res. 65, 934.

8.     IPCC (2022). Climate Change 2022: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change (Cambridge University Press).

9.     Water, U.A.U.N. (2020). United Nations World Water Development Report 2020: water and climate change (United Nations Educational, Scientific and Cultural Organization).

10.   World Wildlife Fund. (2023). Water Scarcity https://www.worldwildlife.org/threats/water-scarcity#:~:text=Billions%20of%20People%20Lack%20Water&text=By%202025%2C%20two%2Dthirds%20of%20the%20world's%20population%20may%20be,and%20economic%20decline%20may%20occur.


Food Bytes: January 2023 edition

Food Bytes is a monthly blog post of “nibbles” on all things climate, food, nutrition science, policy, and culture.

A little warm-up

Are you doing dry, damp, or wet January? Me, semi-dry…I have a good excuse, though. My lovely partner and I had to celebrate with a bottle of prosecco because I have accepted a full professorship at Columbia University’s new climate school, where I will lead their Food for Humanity initiative. I am sad to leave Johns Hopkins, but alas, change is good. I start in June, so get ready Gotham…

I also quit Twitter after 12 years. Felt good. I should have done it years ago…No toxicity! More time! Less self-promotion!

Let’s get the political stuff out of the way…

Is globalization over? The elite will again meet at the World Economic Forum in Davos, Switzerland, for some strained global discourse. When I say elite, gathering of the world’s 0.001 percent. Every year one asks if Davos has relevance or are these elitists more and more out of touch with what is truly happening in countries and communities. This NYT article on how Davos will confront the new world order says it all:

“The World Economic Forum in Davos, Switzerland, finds itself navigating troubled waters. Long the affluent symbol of a globalizing world where the assumption was that more trade would bring more freedom, it now confronts international fracture, ascendant nationalism and growing protectionism under the shadow of war in Europe and sharp tensions between the United States and China.”

I am sure climate change and food security will be on the agenda, but again much of it will be talking, among the elite few, with little action. As it stands, with the global food security crisis, rich countries have fallen short in providing much-needed assistance with increasing risk of hunger and, for some countries, such as Somalia, starvation. Sci Dev wrote an important piece on global starvation looming and rising food prices (see graph below. It deserves attention.

As the world tenses, doing nothing is not good enough, and flying to Davos in your private jet pontificating about poverty is getting tiresome.

If Davos doesn’t get you depressed enough, take a gander at the World Economic Forum’s global risk report. One word: polycrises.

Let’s confront the scary stuff…

California’s “atmospheric rivers”—these doom terms, I tell ya — yield all kinds of chaos for the Californians. The damage due to these intense storms and flooding is estimated to cost the state 30 billion. It is ironic, though, that droughts are a major issue and all roads point to these torrential storms as not helping, but perhaps they will contribute to the necessary snowpack in the long term. What hasn’t been discussed much in relation to storms is the potential damage to crops. California is a massive horticulture producer in this country, growing nearly half of the fruits, nuts, and vegetables in the United States. California’s agriculture also matters to the world because its products are exported to approximately 200 countries. Why is this such as issue? This is why:

“The rains are critical in breaking the worst drought in the US southwest in 1,200 years. The dryness has hurt crops across California’s Central Valley, one of the world’s largest agriculture economies, put large cities under stress, threatened water supplies for many smaller communities, and contributed to some of the largest and deadliest wildfires in state history. Dwindling flow in the Colorado River bordering California has also put hydroelectric supplies in danger.”

There is some hope, though. According to Civil Eats, farms that practice regenerative agriculture seem to weather the storms through innovation.

Let’s give a shout-out to great science…

The AI DALL-E’s rendering of when I asked for “her?” to draw an abstract painting of the Mediterranean diet.

  • Some colleagues at GAIN and Cornell just published this fantastic review on how animal-source foods—meat, fish, eggs, and dairy—can play an important role globally in ensuring healthy and sustainable diets.

  • Another paper by Amanda Woods and colleagues makes the case for resilience in food systems management and governance.

  • Remember that pesky EAT-Lancet Commission report that came out with a planetary diet (very similar to a Mediterranean diet, in my opinion…so what’s the big deal)? Yah, I am guilty of having been a commissioner. Since its publication in 2019, it has been cited about 6,000 times (no joke), and much science has followed. Take this article showing that 86 nations representing 51% of the global population can secure a nationally sourced EAT-Lancet diet from a land-availability perspective. That leaves 3.7 billion living in countries without enough land to source a planetary health diet. I guess trade is important after all!

  • Loved this Nature piece on the importance of indigenous knowledge for food security. This line. YES. “I am under no illusion about what it will take to achieve true collaboration at scale — both at the individual and systemic level. Yet in my interactions with Indigenous people and local communities, people’s generosity and willingness to work collaboratively has impressed me again and again.”

  • A modeling study published in the Global Food Security Journal from a multi-country collaboration examined the impact of the Ukraine-Russia war on food security. Their model show that food trade would decrease by 60%, wheat prices will increase 50%, and severe food insecurity would increase 30% in 2023. Dire.

  • A study in the Lancet Planetary Health examined 83 Food-based dietary guidelines (FBDGs) for their inclusion of environmental sustainability. Of the 83 they examined, only 37 mention ES and of those, none really emphasize why it is important, and how diets can be made to be more sustainable. My question is, who cares about FBDG? Does anyone follow them?? Yes, I get it, they inform public procurement, but they don’t really help individuals with dietary guidance. If you want a snarky take on the United States guideline, listen to this Maintenance Phase podcast (hands down the best podcast on poking holes in nutrition and dietary science).

Still baking, after all these years…

I am still baking, and it has become a relaxing ritual. This weekend? A castelvetrano olive, rosemary, whole wheat sourdough. My prettiest loaf yet! I followed this recipe more or less.

A new year's resolution for the planet

I woke just as the sun rose on the second day of 2023, reflecting, as one does, on what I accomplished over the last year, why it matters, and how I should strive to do things differently in the new year. January always brings about a time for reflection, renewal, and rebirth. For me, the promises I make to myself in the hopeful light of the turning of the clock last only a few weeks, and then I end up reverting toward the same comfortable, survival-mode routine. Maybe a few things change here and there. I tinker around the edges. But nothing spectacularly transformative. And maybe, just maybe, that is okay. This is who I am. These are my habits. My flaws. My warts. My joys. My life. Call it my age, but I guess I am a little less willing to set myself up for failure. Or maybe, I am just letting go.

I say all this to you not as a person who is defeated and cynical but as a person who is hoping for the best but expecting the worst in 2023. I am not an optimist nor a pessimist. I am a realist. I am a “who is going to wash the glass?” This morning, I re-read the Intergovernmental Panel on Climate Change, also known as the IPCC, report on the physical science basis of climate change. This report lays down the hard science of climate change, the repercussions of that change, and future projections under different scenarios of zero to significant action toward mitigation. It is, frankly, incredibly stark. Many of us who work on climate change issues are told to be more positive and report on and present the good news, the silver linings. Of course, not all is doom and gloom, but it comes close. Unlike me, who tinkers on the edges each year trying to meet my new year's resolutions and goals, policymakers and industry players involved in fossil fuels, agriculture, and infrastructure, need to make massive resolutions that are transformative, and they need to stick to them.

This graph below really says it all. It shows the different shared socioeconomic pathways (SSPs), from sustainable to fossil fuel-dependent. Clearly, the world is not moving towards the optimal SSP 1.9. We are more likely hovering toward the SSP 2-4.5 pathway - the middle of the road. The graph shows that if we commit to this SSP, the world will continue to generate greenhouse gases by 2050, with a final tapering off after 2070. By then, the damage will be done - wreaking havoc on human, animal, and plant populations that depend on a more stable planet. Extreme weather events will come with more frequency and devastation. We will see much upheaval, migration, and inequities.

We are running out of time regarding climate change, and the chance to “reset” year in and year out is shrinking. So let’s raise a glass to bold and sticky resolutions that mitigate climate change and ensure that the most vulnerable and disadvantaged have the support to adapt. Let’s make 2023 about the planet.

Source: IPCC, 2021: Summary for Policymakers. In: Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change. doi:10.1017/9781009157896.001. 

Global food system transitions in the last 50 years: what have we learned so far?

We recently published a paper on food system transitions in Nature Food.

Food systems across the world have undergone tremendous changes in the last 50 years, shifting from more rural-based to industrialized and consolidated systems, resulting in both positive and negative impacts across various outcomes, including diets, nutrition and health, environmental sustainability, and livelihoods. In this paper, a food systems typology was used to examine how food systems transitioned historically. Food systems have enabled enough food to be grown to keep pace with the rapidly increasing population while reducing devastating famines that caused hundreds of millions of deaths, but with that great acceleration has come trade-offs and new challenges, particularly with climate change, ecosystem resilience, and deepening issues of inequity, which hamper progress to ensure all people are well-nourished.

This typology has five categories: (1) Rural and traditional, (2) Informal and expanding, (3) Emerging and diversifying, (4) Modernizing and formalizing, and (5) Industrial and consolidated. Categorization is based on the agricultural value-added per worker, dietary change as reflected by the share of dietary energy from staples grains and cereals, urbanization, and supermarket density, which are all closely related to economic growth.  The food system typology covers 155 countries and 97% of the world’s population, with 30-32 countries in each category, as illustrated in the figure below.

Source: Marshall, Q., Fanzo, J., Barrett, C.B., Jones, A.D., Herforth, A. and McLaren, R., 2021. Building a global food systems typology: a new tool for reducing complexity in food systems analysis. Frontiers in Sustainable Food Systems, p.432.

Our analysis reveals that although the affordability of a recommended diet has improved over time, current food systems of all types are falling short of delivering optimal nutrition and health outcomes, environmental sustainability, and inclusion and equity for all.  Six ‘outlier’ country case studies show broad trends, trade-offs, and deviations: Tajikistan, Egypt, Albania, Ecuador, Bolivia, and the United States of America.

Key Findings

Source: Ambikapathi et al. 2022 Nature Food

1.  Recommended diets have become more affordable as food systems have transitioned from rural to industrialized, although access depends on poverty levels which vary within food system types. The figure on the right shows how dramatic the difference is in who can afford a healthy diet.

2.  Increasing diet affordability is a function of multiple forces related to overall structural and rural transformation and food system transition. The process of transition determines who within countries can access an affordable diet.

3.  While food affordability is high, food system objectives to minimize environmental and climate change consequences and to improve nutrition and health outcomes are not being adequately met. Check out the figure to the right that shows the proportion of GHG emissions from each of the eight food system supply chain stages (land-use change, production, processing, packaging, transport, retail, consumption, end of life) across the five food system typologies. In general terms, land-use change and production practices constitute the primary sources of GHG emissions of all categories. However, as food systems transition from rural to industrialized, the share of these two main sources of emissions changes.

4. The reality of current food system transitions across the typology is far from a sustainable food system transformation. Such a transformation towards sustainable food systems will require addressing these challenges directly and setting a global agenda with equity, nutrition, and the environment at its core. In many cases, this agenda will challenge historical trends and processes that have led us to where we are today.  

5. The future will not look like the past and indeed cannot look like the past if we are to achieve sustainable food system transformation. Latecomers to the process of structural transformation face a very different world and a much more challenging economic context. The very process of food system transitions incurred by countries further along with structural transformation and the negative environmental and nutritional outcomes they engendered has changed the parameters of success for future transitions. This, coupled with variation in performance across countries within the five categories of the typology, suggests that we will see unique and heterogeneous patterns of food systems transition.

Implications

1.     Effective policies include reliable and well-targeted safety nets, school feeding programs, equitable distribution of land with appropriate environmental management and tenure policies and creating employment that provides increasing incomes relative to food prices to achieve affordable, nutritious diets.

2.     Food system transformation towards sustainable food systems will require setting a global agenda with equity, nutrition, and the environment at its core.

3. There are clear future research needs. More in-depth country-level case studies and high-quality sub-national data are needed to identify a range of effective solutions and the political economy tensions that hinder sustainable food system transformation.

Food Bytes: October 2022 Edition

Food Bytes is a monthly blog post of “nibbles” of information on all things climate, food, and nutrition science, policy, and culture.

It’s been a long while since I posted a Food Bytes edition, and so much has happened in the food space in the past year. First, a UN Food Systems Summit happened, but I remain quite unclear on what was achieved or what will come of the year-long work leading up to the event. Second, a devastating conflict between two breadbasket countries trudges on, putting food security concerns back on the geopolitical agenda. Third, extreme weather events, many related to climate change, unrelentingly warn us that our ability to feed a world of 8 billion (yikes) is precarious and precious. But science is there to nudge us, generating new knowledge on why we and every other species are here, what accelerates us, what destroys us, and where we are heading. Charles Mann wrote in The Wizard and the Prophet (a stellar book about William Vogt and Norman Borlaug’s discordant visions to feed the world):

Another thing this book is not: a blueprint for tomorrow. The Wizard and the Prophet presents no plan, argues for no specific course of action. Part of this aversion reflects the opinion of the author: in our Internet era, there are entirely too many pundits shouting out advice. I believe I stand on firmer ground when I try to describe what I see around me than when I try to tell people what to do.

I resonate with these sentiments. Even though science is plagued by warts, hiccups, and flaws, catalyzing evidence and data to help describe the world matters because it helps us understand nature, people, and the planet. With that background in mind, this month’s Food Bytes is all about highlighting the science community’s observations and uncertainties of a changing world and what it means for food systems and climate change. I purposely do not highlight the work of my team and collaborators, but if you are curious about when we do, you can look here.

Source: McKay et al. SCIENCE 9 Sep 2022 Vol 377, Issue 661 DOI: 10.1126/science.abn7950

Let’s get the dark stuff out of the way. A paper by David Armstrong McKay and colleagues updated data showing that holding at 1.5°C will trigger multiple climate tipping points. What are these tipping points? Things like ice sheet “collapses,” forest “diebacks,” and permafrost “abrupt thaws” (see the figure to the right). These terms are downright scary but very plausible under different modeling scenarios. Okay, onto more uplifting news — KIDDING! Another study has shown that over the last 40 years, the Arctic has warmed four times faster than the rest of the world, also known as Arctic amplification. These are massive global shifts that will further warm the planet, creating all kinds of chaos. What does it mean for us wee creatures living in our humble abodes? Well, the news is not totally uplifting on that front either. We are and will be deeply impacted by climate — and no one is immune. Research by Sylvia Blom and colleagues showed that repeated, extreme heat shocks impact early child nutrition — both chronic and acute malnutrition. They show that in 5 West African countries, a 2 °C rise in temperature will increase the prevalence of stunting by 7%. As the two latest 2022 Inter-Governmental Panel on Climate Change Reports on adaptation and mitigation, also known as the IPCC, argue, we still have time to act, although when you read it, you may want to have a nice glass of scotch in hand. While the window remains open, it is closing, and fast. We need to make massive changes to the way we live, much of that involving our use of resources. A recent Nature Sustainability paper showed that no country meets basic needs—such as nutrition, sanitation, and access to electricity—for its citizens at a globally sustainable level of resource use. To meet needs, we need to use resources somewhere between 2-6 times more to meet everyone’s needs. Gulp. Just take a look at the difference between the United States (a) and Sri Lanka (b) in the figure below. Blue wedges show social performance relative to the social threshold (blue circle), whereas green wedges show resource use relative to the biophysical boundary (green circle). The blue wedges start at the center of the plot (which represents the worst score achieved by any country), whereas the green wedges start at the outer edge of the blue circle (which represents zero resource use). Wedges with a dashed edge extend beyond the chart area. Ideally, a country would have blue wedges that reach the social threshold and green wedges within the biophysical boundary. Look at the inequities comparing the two countries!

Source: O’Neill, D.W., Fanning, A.L., Lamb, W.F. et al. A good life for all within planetary boundaries. Nat Sustain 1, 88–95 (2018). https://doi.org/10.1038/s41893-018-0021-4

The research and science in understanding the impacts of climate change on food systems and vice versa are growing exponentially. It is hard to keep up with the literature and weed out the noise. One area that deserves more attention is the impact of food trade on global greenhouse gas emissions and the environment—particularly land-use change—a significant source of emissions coming from food and agriculture. A study showed that 27% of land-use emissions and 22% of agricultural land are related to international trade (2004-2017)—food products consumed in a different place from where they were produced. The largest land-use emission transfers come from Indonesia and Brazil to China, the U.S., and Europe. A PLoS paper examining the future of trade shows that if we keep managing and governing global trade as is, food systems will be misaligned with dietary health and sustainability outcomes.

Perhaps one solution is through changing agriculture subsidy policies. The UN Food and Agriculture Organization (FAO) published their annual SOFI report and highlighted the need to transform agriculture subsidy programs around the world towards those that generate and produce healthier food products. Marco Springmann at Oxford modeled the impacts of subsidy policies that focused on nutritious foods and found multiple benefits across both environment and health. I am really uncertain about the political appetite to change subsidies. Talk about vested interests… Speaking of priorities, Ben Davies and colleagues argue that making big transformative policy changes across food systems is wonderful, but don’t do it “on the backs of the rural poor.” Although there are 2.7 billion people engaged in small-scale food production and 1.1 billion people concomitantly living in extreme poverty while working in agriculture, they are often ignored in the “transformation” story.

Affordability of a healthy diet grouped by five different food system typologies, showing transition of food systems. Source: Ambikapathi, et al Nat Food 3, 764–779 (2022). https://doi.org/10.1038/s43016-022-00588-7

Positive transformation of food systems is not easy as history suggests. As Ramya Ambikipathi shows in a recent Nature Food paper, food systems have shifted from predominantly rural to industrialized and consolidated systems. Historically, incomes have risen faster than food prices as countries have industrialized, enabling a simultaneous increase in the supply and affordability of many nutritious foods. Evolving rural economies, urbanization, and changes in food value chains have accompanied these transitions, leading to changes in land distribution, a smaller share of agri-food system workers in the economy, and changes in diets. While the affordability of a recommended healthy diet has improved over time, food systems overall are falling short of delivering optimal nutrition and health outcomes, environmental sustainability, and inclusion and equity for all. Another fantastic paper by Jeff Waage and colleagues in Lancet Planetary Health shows the complex and risky relationship between agriculture and infectious disease, particularly in low-income and middle-income countries that are undergoing rapid food system transitions. They remind us that lessons can be drawn from COVID-19 and the rise of zoonotic spillover events within food systems should be prioritized (and minimized) on the political agenda.

Ensuring that everybody gets access to and consumes a healthy diet will remain a global challenge. The metrics, indicators, and data in understanding what people eat and why are improving. Just check out the Global Diet Quality Project, which collects dietary quality data in the adult population across countries worldwide using the Gallup poll and provides tools to monitor diet quality within countries. Wow. I hear rumblings of a global report coming out soon, so stay tuned. There has been a whole range of papers coming out on diet quality. Victoria Miller at Tufts University is on a roll. In one recent Nature Food paper, she examines diets across 185 countries from 1990 to 2018 using the Global Dietary Database (estimates and modeled). Their assessment shows that diet quality is modest at best but varies significantly depending on where you live, how old you are, and how much education you have. No surprises, but good to see more data emerging from this database. Miller and colleagues also published a more specific paper examining the consumption of animal-sourced foods worldwide showing that meat consumption is lower or higher than optimal intakes depending on the population. Another Miller paper published in JAMA examines the association of specific dietary factors with coronary heart disease, stroke, and diabetes using a systematic review. The table below summarizes the relative risks of the associations of nutrients with heart disease and diabetes events. Bottomline? Eat your fiber.

Source: Miller et al JAMA Netw Open. 2022;5(2):e2146705. doi:10.1001/jamanetworkopen.2021.46705

Another emerging area gaining significant traction with scientific consensus is ultra-processed foods (UPFs), a term loathed by the food industry and a handful of nutritionists. The majority of those working in nutrition epidemiology and public health largely agree that UPFs—food-like substances extracted from foods, such as fats, starches, added sugars, and hydrogenated fats that also contain additives like artificial colors and flavors or stabilizers—are detrimental to human health across a bolus of outcomes. Many people argue that these foods should be regulated, avoided, and minimized in the global food system. If you want to hear more about this ongoing debate, check out this BBC podcast and this online debate with some heavy hitters in the space like NIH’s Kevin Hall, Marion Nestle, and Mike Gibney. The next frontier for these foods is their environmental impact. While a handful of papers argue that these foods have a significant environmental and climate footprint, the evidence is scant, and much more needs to be done in this space.

The question is, are alt-meats in this category? The pace of science in this space is hard to keep up with as there is a lot coming out in the grey literature (see the IPES report and the OECD report as examples) along with peer-reviewed publications, but some of what is available often bends towards ideology and less science. Same with plastics. There is deep concern about microplastics showing up all over the place, including food, but the evidence and impact of these plastics on health outcomes need much more exploration. So while Mr. McGuire told Ben in The Graduate, that the future lay with one word, plastics, we may need to re-examine that advice in light of the fragility of our world.

We may not have a choice but to consume alternative proteins

Climate change is having profound impacts on the ability to grow both foods for humans and feed for livestock. Growing food and feeding livestock, in turn, exacerbates climate change. Livestock raised for beef is responsible for 6 percent of total greenhouse gas emissions largely in the form of methane. Livestock is also the number one driver of deforestation around the world, reducing the chances for large forest biomes to serve as carbon sinks.

While these stresses continue to rise if no significant action is taken to mitigate climate change, demand for meat is rising all over the world. According to the UN Food and Agriculture Organization, beef consumption has been steadily rising over the last few decades, and as people become wealthier, the more meat they consume. And people, well, like meat!

Some tech companies have come up with a solution—alternative proteins—which include lab-grown meat, plant-based meat, single-cell proteins from yeast or algae, and edible insects. The lab- and plant-based alternative innovations mimic the taste, smell, and texture of meat and could be significant disruptors, eliminating the need for people to raise or consume animals.

As of now, the products available for consumers are mainly plant-based proteins like Impossible Burger and Beyond Beef. Data suggests that these foods are tasty to most consumers and have lower environmental footprints and greenhouse gas emissions than beef. They also have benefits for those who care about animal welfare.

They are however under scrutiny about their health properties and cost. Some argue these foods are overly processed, with a lot of artificial ingredients to get them to a state of palatability. Beyond Burger has approximately 25 ingredients whereas beef has just one ingredient – muscle tissue. They are also costly. One Impossible burger in Washington DC’s Founding Farmer restaurant costs $17.50 as compared to the all-beef cheeseburger at $14.50.

The products in the R&D pipeline – such as lab-grown meats – will have to undergo significant regulation by governments and there is the issue of scale. In the film, Meat the Future, the company Upside Foods (formerly known as Memphis Meats), which is using cells taken from an animal to grow meat, is challenged in making enough products at scale to feed the world’s growing population. While these are hurdles, there are some glimpses of promise. Those that have tried these products are pleasantly surprised at how similar they taste to the real thing and issues of scale are just temporary roadblocks.

Yet, will consumers accept and embrace these foods? The backlash against genetically modified foods shows early signs of what may come as companies begin to get lab-grown meats to market. Many consumers may argue these foods are fake and may be hesitant about their food being “grown” in Petri dishes. 

The big issue is, that we may not have a choice but to eat lab-grown meats. It will be very difficult to raise livestock in a hotter world. Not only will feed and water be scarce, but hotter climates wreak havoc on the health of the animals. These projected adverse effects will put premiums on the price of meat in the grocery store.

So while the world can be picky for the time being, these new foods may become our mainstay survival foods because they may be the only option. To ensure these foods are affordable, accessible, and acceptable to consumers all over the world, and not just curious rich people, several things need to happen.

First, companies producing these foods need to ensure transparency in how these foods are produced, and their impacts across a broad range of outcomes, particularly health and nutrition. There is a need for transparency regarding their nutritional content that is easy for consumers to understand and find. Companies should take lessons from how genetically modified foods were communicated and the fears and doubts they have raised among consumers.

Second, for those products that have unhealthy ingredients with losing palatability, the companies should work hard to reformulate the products to decrease the content of sodium and unhealthy fats. They should also work to fortify these foods with adequate micronutrients.

Third, these foods should be low cost, or real meat should be more expensive, keeping with the true costs to produce beef. As the demand for these alternatives increases and more companies come on board with new products, as with any economies of scale, the price will come down.

Last, while the innovation for these new foods is tempting, there are many traditional foods such as legumes, insects, and algae that have important nutritional value, particularly protein, have low environmental footprints, and do not require raising animals. These traditional foods, while traditional, may offer low-cost, low-resources alternatives to shiny and new future foods.

The World’s Food System Is Too Dependent on Wheat

This opinion piece was originally posted on the Bloomberg Opinion.

The Ukraine war highlights how reliance on a few big staple crops threatens food security and global nutrition.

Stunned by Russia’s assault on Ukraine, Europe is scrambling to diversify its energy supply — from piped Russian gas to liquified natural gas, more renewable power and nuclear power. In the same way, and for much the same reason, the ongoing war should push countries to shift and diversify their food supply — to make it more secure and, at the same time, improve nutrition worldwide.

Russia and Ukraine together supply 30% of the world’s wheat. This is why the war has caused wheat prices to skyrocket, along with the prices of many other food commodities. From February to March, the U.N. Food and Agriculture Association’s Food Price Index leapt 12.6% to an all-time high. This threatens people around the world with unprecedented food insecurity.

It also highlights the need to reform the global food system, which now leaves too many people dependent for nourishment on just a handful of mass-produced grains, including wheat, rice and corn.

To deal with the immediate shortages, farmers in the U.S., India, Canada and elsewhere will have to plant more wheat. And people worldwide will have to replace wheat with rice and other available grains. In the long term, though, this crisis provides an opportunity to change the face of agriculture and reduce the world’s dependency on wheat and other big staple crops.

Accomplishing this shift will be politically challenging. Many countries have entrenched agriculture subsidies that support big commodities including corn, rice, wheat, oils, sugar and soy, and ensure that they are grown at massive scale using uniform farm production practices. In the countries that grow two-thirds of the world’s crops, governments provide $540 billion a year in agricultural support. The U.S. alone spends $16 billion annually on farm subsidies, 80% of which goes to the largest 10% of farms.

This paradigm has many flaws. After all, there will always be risks in relying too heavily on one grain or just a few. It makes it difficult to address disruptions in supply caused by conflicts, protracted crises and fragile states — as the conflict in Ukraine makes clear. And in addition to geopolitical problems, there is the age-old but now growing threat of bad weather.

Heat waves, droughts, floods and cold spells can devastate wheat, corn, soy and rice crops. Because of climate change, extreme weather has already reduced harvests enough to push food prices up to their highest levels in 40 years. Climate change also increases the risk that such extreme weather events might occur at various locations in the same season. This phenomenon of “multiple breadbasket failures” stands to compromise billions of people’s access to food.

Subsidies for the big crops also neglect the need to promote healthy diets. Take wheat, for example. Whole unrefined wheat is a major source of starch and energy, as well as protein, vitamins (notably B vitamins), dietary fiber and phytochemicals. But demand for wheat has been rising globally because of its unique gluten properties, which make it also an ideal component of bread, noodles, pasta, cookies, crackers and many other baked foods and snacks. These highly processed foods, which now constitute a significant share of the world’s diet, are depleted of healthy nutrients and contribute to poor health.

Over the past 50 years, farm subsidies, supported by complementary research and development efforts in agriculture-dependent countries, have made rice, corn and wheat the world’s most dominant crops, accounting for two-thirds of global food-energy intake. Alternative staples such as sorghum, millet, rye, cassavas, sweet potatoes and yams haven’t disappeared — at least not yet — but they have become steadily less important.

To encourage a more diverse and resilient food supply, countries should begin reorienting agriculture subsidies toward fruits, vegetables, nuts and legumes and other nutritious foods. A recent study suggests that if half of all agriculture subsidies worldwide were repurposed to support the growing of foods that benefit human health as well as the environment, it could increase the cultivation of fruits and vegetables by as much as 20% and reduce greenhouse-gas emissions from agriculture by 2%.

Shifting agriculture subsidies is no easy lift. Many farmers depend on them to support their livelihoods, and many would consider it incredibly risky to make major changes in what they grow. But with climate change increasing and geopolitics unstable, change is becoming more and more necessary. And if people are to avoid chronic health problems such as diabetes and heart disease, they need assistance from the food system to adopt more nutritious diets. The global disruption caused by the war in Ukraine should prompt governments to reconsider their efforts to influence the crops farmers grow and move toward encouraging a more diverse food supply.

The Future of Food

Growing, producing, and shipping food are big contributors to climate change. According to the UN Food and Agriculture Organization, about one-third of the global greenhouse gas emissions come from the world's food systems. Food is "an instigator of climate change and it's a victim of climate change," said Jessica Fanzo, director of the Johns Hopkins Global Food Ethics and Policy Program and author of Can Fixing Dinner Fix the Planet?, in an interview with Mike Walter of CGTN.

One of the solutions is changing individuals' diets, what Fanzo and fellow food researchers from the EAT-Lancet Commission call a "planetary health diet." The diet is high in fruits and vegetables, as well as beans, legumes, nuts, and seeds, while food from animal sources, including meat, fish, and dairy, are low. Not only is this sustainable for the planet, "it's a very plant-based diet that meets nutritional needs, decreases your risk for non-communicable diseases like cardiovascular disease and diabetes and stroke, all these long-term, chronic, quite costly diseases," Fanzo said.

Bringing back community agriculture services

With food insecurity rising worldwide and nutrition-related illnesses proliferating, countries want to encourage healthier eating. But how can they ensure people are able to buy and prepare diverse, nutritious foods when farmers produce so little of them? National agricultural policies are generally designed to support the cultivation of staple grains such as corn and rice, some oils, and sugar. A recent paper shows that 1/3 of global farms cultivated maize and 1/5 cultivated wheat alone! These foods feed the world amply, and cheaply, but some in the form of highly processed foods.

@FAO

@FAO

Another issue is the significant loss and waste of perishable fruits and vegetables, meat and dairy products because of inadequate food storage, poor roads, and people’s lack of access to modes of preserving food for long-term storage. Such inefficiencies along the food supply chain drive up the cost and limit the supply of nutritious, fresh foods in rural and urban areas alike.  In Ethiopia for example, perishable foods such as eggs, dairy, and fish are 8-10 times more expensive than starchy staple calories due to supply constraints.

Turning around such entrenched food systems may seem daunting. But it can be done, beginning at the grass-roots level by improving community-based agriculture extension programs. Extension workers are “door-to-door” or farm-to-farm advisers who translate agriculture science into practical applications for farmers. They help solve problems and provide the training and technology farmers need to improve their operations profitably. Extensionists, as they are called, can also be critical mediators in times of natural disasters or outbreaks of disease among livestock.

A study done in 2014 by the Global Forum for Rural Advisory Services estimated there are 1,059,528 extension agents worldwide, but that could be an underestimate. The range of extension agents in each country varies, with some countries having very few—Barbados has 6—whereas other countries have more—China has 615,000. But, of course, that depends on the number of farmers in the country and how many people each extension agent serves.

Ideally, extensionists can steer farmers toward cultivating more nutritious foods and help them do so profitably. They can guide farmers to save heirloom seeds and improve agronomic practices to produce nutritious crops such as horticulture and raising poultry and goats. They can provide training to farmer families on food preparation and nutrition. They can help farmers adopt cultivation and fertilization practices that protect the environment, limit greenhouse-gas emissions, and help store carbon in the soil. And last, they can advise on post-harvest and storage technologies to minimize food loss on farms.

However, in many countries, they lack the training, tools, transportation, and communication tools to reach farmers. Nutrition training provided to extension agents at agricultural technical schools and universities is ineffective and inadequate, which impedes the ability of agents to identify nutritional needs and provide advice or solutions. They also do not have tools to share with communities nor the training to raise awareness of nutrition as a priority.

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In many countries, extensionists also lack the tools that would help them work efficiently with more farmers. For example, in some parts of rural Africa, extension agents do not have mobile phones (or top-ups) to contact farmers about real-time issues like food prices in regional markets or motorbikes to reach far-flung communities. With COVID-19, many extensionists cannot get out to the field, so in places like China and Iran, extensionists are using smartphones and the radio to communicate market information and technical support along with public health safety. Farm Radio International is working with 1,000 stations in Africa to help get out information through extension agents.

It starts at the university level—improving extension curricula in universities or after high-school technical training schools. Investments in refresher certification programs for extension agents are needed in most places globally as technologies change and the latest science and technological know-how on agronomy, nutrition, and climate science tools become available. Continual updates to training modules of extension agents such as the New Extensionist Nutrition Learning Kit developed in Rwanda can strengthen training in nutrition within agriculture. Many local non-governmental organizations can provide this training along with the Food and Agriculture Organization in partnership with Ministries of Agriculture.

Techniques employed by extension agents such as peer-to-peer engagement through model farmers, community champions using a “train-the-trainer” approach, or the “walk-and-talk” methodology, wherein agents interact with client farmers through hands-on demonstrations. One example could be forest walks with farmers. Extension agents could teach farmers how to harvest wild, nutrient-dense foods, followed by demonstrations in preparing and incorporating the food into conventional dishes. The International Fund for Agriculture Development (IFAD) has a program, The Last Mile, which is expected to engage 15,000 extension agents in 18 countries to provide business and market-oriented skills to over 1.5 million smallholder farmers over the next five years. 

Last, women extension agents should be promoted and empowered. Only 15% of extension agents are women, and only 5% of women farmers reap the benefits from extension services. Most extension services have traditionally targeted their resources and interventions towards male farmers. Women extensionists understand the needs and challenges of women farmers, particularly in low- and middle-income countries where 45% of the agriculture workforce is made up of women. They should be invested not only to jumpstart careers but also to support the many women working in food systems that ultimately feed us.

Investing in the people who best understand their communities' needs, be it health or agriculture community workers, is critical to address the challenges that farmers face. However, it won’t be enough to transform global agriculture. Governments, international organizations and the private sector must invest in infrastructure along the entire food supply chain to help farmers grow, store and deliver perishable, nutritious foods. In addition, there is a need to provide farmers the latest climate-smart technologies and tools that would allow them to be resilient when facing natural disasters and other shocks. Insurance and credit are also crucial as safety nets in these uncertain times. That said, face-to-face contact with people exchanging ideas, advice, and knowledge isn’t a bad place to start. So let’s reinvigorate and invest in extensionists.

Can Fixing Dinner Fix the Planet?

Two years ago, I embarked on the writing of my very first book. Coming from a field of expertise that values peer-reviewed scientific publications more than books, I did not think it was in the cards to consider authoring a book about my discipline and my experience working in that discipline. But here we are, and tomorrow, my JHU Press Wavelength series trade book, Can Fixing Dinner Fix the Planet? will be released. The pandemic helped, unfortunately. It nudged me to sit still and put pen to paper.

The book investigates the interactions among food systems, diets, human health, and the climate crisis. It draws on my experiences (along with my team and many colleagues) working and living in Africa, Asia, Europe, and the Americas. It describes how food systems must change to slow and reverse the stark trends we see with increased hunger and obesity, catastrophic climate change, and inequities. The book draws attention to the idea that the very nature of food and food systems can play a significant role in fixing these vexing challenges and bring communities together.

Food books abound—cookbooks by celebrity chefs (thanks Anthony Bourdain!), history of food and cuisines, and self-help diet books. My book does not delve into these areas much. Instead, it delves deep into politics and shows that if we take a “business as usual” path of how food systems have, are, and will operate, there will be significant negative consequences on human and planetary health. It provides examples of what can be done by the various actors like government and food and agriculture industries to promote healthy, sustainable, and equitable diets, sustain the earth’s biodiversity, and protect the environment and all species living on the planet. And last, it raises readers’ food and environmental literacy and empowers readers to take immediate and long-term changes by helping them make informed decisions when they walk into restaurants, grocery stores, farmers' markets, and their kitchens.

The book changed the way I communicate my work. It is not easy to write about a complex topic like food systems and ensure that it inspires eaters, global experts in governments, and those working in and shaping food systems to make better decisions. I tried my best to bring to life some of my experiences working in different countries—from very poor to prosperous—and the experiences of those I have worked with and shared time with in deeply rural and urban pockets of the planet. It provides a nuanced story that takes you away from computer and desk research to farmer’s fields, families’ kitchens, and United Nations’ working forums.

I hope the book shows readers how our everyday diets are the products of massive, interconnected, and highly complex food systems that extend from the seedlings in a farmer’s field to the global distribution and marketing networks that deliver food to our plates. These systems have direct and substantial impacts on poverty, the planet’s natural resources, the nutrition of individuals and populations, the composition of the atmosphere, and social equity. They also are incredibly vulnerable to the climatic changes that we have already seen and that will accelerate in the future.