What happens to cuisines when cultures change, or when culture becomes globalized? Naturally, so do our diets—and our health. Food research by the U.S. military, particularly during and after World War II, led to the creation of consumer products that could also be used as wartime rations, which meant heavy processing. And one consequence of the Allied victory is that the world has largely adopted America's processed-food diet, which is a key factor for the obesity crisis the world now faces, with around 13 percent of the world's adult population considered to be obese in 2016. According to the 2020 Global Nutrition Report, while malnutrition is the leading cause of death worldwide, this crisis is worsened by obesity, which remains three times more common than hunger.
The worst diet in the world
The American diet, according to the World Resources Institute (WRI), a global nonprofit research organization, is the worst in the world in terms of overconsumption and waste. This conclusion was drawn from an ongoing study conducted by the Institute, which found that the average American diet contained almost 500 more calories than the global average. This information is backed up by the fact that over one-third of American adults and one in every five children in the country are obese, according to government data from 2015-2016. And it's going to get worse: A December 2019 Harvard study predicts that half of American adults will be obese, with a quarter suffering from severe obesity, by the end of the decade. For the most part, this health crisis is due to eating meat and sugar.
The United States is one of the highest meat-consuming countries in the world per capita. A 2015 study found that Americans' source of protein mainly comes from animal sources, primarily chicken and beef. In order to sustain this, between 80 and 90 percent of all agricultural land use in America is reserved for the production of animal protein, according to WRI findings.
In 2015, the Mayo Clinic Proceedings, a peer-reviewed medical journal, found that the high consumption of added sugar was fueling the diabetes and obesity epidemic in America. In particular, the study found that fructose, the type of sugar primarily found in processed foods, "metabolized very rapidly and leads to harmful fat storage, worsening insulin levels, inflammation, and high blood pressure." According to the National Cancer Institute, the U.S. federal government's main agency for cancer research, "there is consistent evidence that higher amounts of body fat are associated with increased risks of a number of cancers," including those affecting the breast, gallbladder, colon/rectum, pancreas, kidney, and liver, as well as multiple myeloma and meningioma. The Centers for Disease Control and Prevention warn that obese people have an increased risk of many serious diseases and health conditions, including coronary heart disease, stroke, osteoarthritis, sleep apnea, and mental illness such as clinical depression and anxiety.
In January 2019, the Lancet Commission on Obesity, a joint venture between World Obesity Federation, Auckland University, George Washington University, and the Lancet, released its first report on the state of global diets. Reviewing hundreds of studies conducted over the past two decades, the report concluded that "malnutrition in all its forms, including obesity, undernutrition, and other dietary risks, is the leading cause of poor health globally." This translates to around 2 billion overweight people around the world, with excess body weight contributing to 4 million deaths annually and a further 815 million individuals who are undernourished.
In another report released in August 2019, an international team of researchers from Spain, Germany and Chile conducted a meta-analysis of 103 studies looking into obesity among children in 28 European countries. The authors concluded that the number of overweight and obese children had steadily increased from 1999 to 2006, and then once again from 2011 to 2016.
Both reports concluded that the high presence of unhealthy diets reflects a global failure to address this major health concern. The Lancet Commission attributed a portion of the blame to food-industry lobbies, which have thwarted efforts to improve dietary guidelines, as well as food producers' influence on policy, urging governments to redirect subsidies for beef, milk, sugar, corn, and rice toward healthier foods. The severity of these findings is underpinned by the growing climate crisis and its impact on agriculture and our ability to address obesity and malnutrition.
The Commission criticized world leaders, saying, "The policy responses from national governments to obesity, undernutrition and climate change as separate problems have been slow and inadequate." The authors concluded their report with an urgent call to radically rethink the business models, food systems, civil society involvement, and national and international governance contributing to this prevailing situation. "[A] transformative social movement, building through the local, national, and global levels, is needed to overcome the policy inertia," they wrote in their policy brief. But before we rethink the problem, it's useful to diagnose it more fully.
The findings echo those of an earlier paper arguing that the common view that obesity is driven by either personal choice or the environment of a false dichotomy. "While we need to acknowledge that individuals bear some responsibility for their health, we also need to recognize that today's food environments exploit people's vulnerabilities and make it easier to eat unhealthy foods," said Christina Roberto, the lead author of the paper, one of a six-part series on obesity in the Lancet published in 2015. Roberto, an assistant professor of social and behavioral sciences and nutrition at Harvard T.H. Chan School of Public Health, calls for "smart food policies" to combat the failure of governments to reverse the global obesity epidemic, contending that the current food regime "reinforces preferences and demands for foods of poor nutritional quality, leading to environmental changes that further encourage consumption of unhealthy foods."
Obesity: America's number one export?
The typical Western-style diet of refined carbohydrates, added sugars and fats (collectively known as highly processed food), and large amounts of animal protein has steadily caught on around the world. In India, for example, diabetes tripled between 1995 and 2014, with 66.8 million people suffering from the disease. "The influence of globalisation and urbanisation are the single biggest factors for India's diabetes epidemic," V. Mohan of Dr. Mohan's Diabetes Specialities Center, Chennai, and founder of Madras Diabetes Research Foundation explained in an interview with India's national television network NDTV. "Our eating habits now resemble the west and we've adopted sedentary lifestyles."
China too has witnessed a drastic change in eating habits over the past two decades. According to the World Resources Institute study, this trend has seen China's obesity rate triple between 1991 and 2006. A study published in March 2019 by the journal Lancet Diabetes & Endocrinology found that 20 percent of children in China are obese—up from 5 percent in 1995.
Due to these changes in the way the world eats, "Poor diet is the number one risk factor driving the world's disease burden," according to a report published by the Global Panel on Agriculture and Food Systems Nutrition, an independent group of experts on nutrition and health.
"If you look at all the diet-related risk factors for health, they outweigh the burden of all of the other risk factors combined," Lawrence Haddad, one of the report's authors and a former senior fellow with the International Food Policy Research Institute, told NPR.
The report outlines this problem in greater detail, linking the health effects to a shift in lifestyle. Although many countries have seen a growth in income and general living standards, this has been met with a concomitant rise in the consumption of processed foods and sugary drinks, with the sale of processed foods growing at the fastest rate in developing countries.
The report attributes this trend to "changing food environments in most countries." As healthy food becomes more expensive, populations are turning to cheaper alternatives. "The price of fruits and vegetables is going up and up," Haddad said. "The price of processed foods is going down and down."
According to Haddad's report, if we project the current trends, by 2030, "we may have as many as 3.28 billion overweight and obese people … the vast majority of them in low- and middle-income countries."
Why the Western-Style diet is so bad
It's easy enough to identify the problem of obesity, but understanding why this occurs is not as straightforward.
A 2018 article published by the Conversation explored this very question. The article, titled "Immigration to the US Westernizes Asian Guts," looks at how changing diets affect our digestive systems, specifically "the trillions of microscopic creatures that live inside us all—the human microbiome." The authors, Dan Knights and Pajau Vangay, are scientists from the University of Minnesota whose research is focused on how changes to the gut microbiome affects our health—a fact science now widely recognizes is "associated with nearly every major chronic human disease," including obesity.
So how do changes in diet affect the gut microbiomes? This was the subject of a recent study conducted by the article's authors. Entitled the Immigrant Microbiome Project, the research looked at what happens to people's gut microbiomes and their health when they move from a developing country to the U.S., and whether this contributes to obesity. What they discovered is that the "diversity of the gut microbes declined across generations" of immigrant populations in their study, with an even "greater decline in diversity" among obese individuals.
From this research and previous studies, the scientists were able to conclude that "obese individuals have a lower microbe diversity in their guts than their lean counterparts." One of the main contributing factors identified in the study was a change in diet. The authors did acknowledge there are likely more complex causes associated with these changes to the gut microbiome but recognized a strong correlation between their results and previous studies that have shown that having the wrong microbes can cause obesity in mice.
This conclusion was recently reiterated in a study published in the Journal of Clinical Investigation. The research, conducted by a multi-institutional team led by researchers at Baylor College of Medicine, revealed a "previously unknown gut-brain connection" between high-fat diets and weight gain. And a study published in the journal Cell in July 2019 found links between obesity and eating "ultra-processed" foods that disrupt the gut-brain signals that would normally tell us we're full.
An October 2019 article by registered dietitian Jillian Kubala published on Healthline provides further statistical evidence that backs up this research. Referencing a slew of studies, Kubala illustrates how an increase in the consumption of processed foods high in refined sugar has contributed to a rise in obesity, type 2 diabetes and other chronic diseases. She also examines how vegetable oils high in trans fats, commonly found in processed foods, contribute to an increase in the risk of heart disease. How? Studies have shown that the high presence of fatty acid in this sort of diet "gets incorporated into our cell membranes and body fat stores," which through a process of oxidation can damage molecules such as DNA and "lead to actual harmful structural changes in our bodies," writes fellow Healthline author Kris Gunnars.
Another serious concern around this type of diet is the devastating impact it's wreaking on the environment. Palm oil, the highly sought-after product of fruit from the African oil palm tree used in the production of processed foods, has spawned a massive worldwide industry to meet demands. A consequence of this demand is that many acres of rainforests have been cleared in Asia, as well as North and South America, to make space for these trees, contributing to the significant loss of animal habitats. The Independent reported in August 2018, that the effect of this industry has led to "the death of an estimated 100,000 orangutans" and contributed to climate change due to the "high amounts of carbon emissions" produced in the process. A December 2019 analysis published by journal Obesity estimates that obesity contributes to an extra 700 megatons of carbon dioxide emissions per year globally—nearly the amount of Germany's man-made annual emissions.
So what is to be done? For one, we need to eat a lot less meat. As reported by WRI, beef is "the most environmentally consequential food we eat, accounting for nearly half of Americans' dietary footprint." To avoid having obese children, parents—especially those managing the diets of more than one child, which can be time-consuming—have to consider meals and mealtimes, which means less McDonald's. "With multiple children you're scheduling a little bit more of your meals. So we're going to have more at-home meals. We're probably going to have less fast food," said Chelsea Kracht, a researcher at Louisiana State University's Pennington Biomedical Research Center and lead author of a 2019 study looking at the eating habits and weights of only children, in a recent interview with the Journal of Nutrition Education and Behavior.
A report published in 2019 found a high correlation between the prevalence of processed foods and the obesity epidemic in the U.S. "Chronic disease in later years is not predestined, but heavily influenced by lifestyle and diet," said the paper's co-author Leigh Frame, assistant professor of clinical research at the George Washington School of Medicine and Health Sciences in Washington, D.C. "Decreasing obesity and chronic disease in the U.S. will require limiting processed foods and increasing intake of whole vegetables, legumes, nuts, fruits and water."
On a global level, if we don't address this overconsumption, we will find it extremely difficult to limit global temperature to well below 2° Celsius (3.6° Fahrenheit) above pre-industrial levels, which is required to avoid the worst impacts of climate change. Highly processed foods like processed meats, and sugary foods and drinks are a double-edged sword, as they are unhealthy for both people and the planet—not to mention the billions of animals suffering across the food system.
"If you think about it, highly processed foods are a waste," says Sharon Palmer, a registered dietitian and plant-based nutrition and sustainability expert. "If we have a limited amount of land and we have to keep producing more food to feed the planet, we shouldn't be wasting any land producing food that does nothing but hurt people's bodies."
The main hurdle, it seems, is time—and taste. "[M]ost people don't have the time or resources to prepare farm-to-table meals," notesBarbara Rolls, an obesity researcher at Pennsylvania State University. "If we had to live without processed foods, I don't think we would be able to feed the population—nor would people like it."
Fortunately, as WRI reports, we could be heading toward a "more sustainable American diet, with a greater share of plant-based foods." As consumers, we have the power to make this prediction a reality by demanding more ethical alternatives and ultimately changing the way we eat. It's already happening: As a November 2019 Newsweek article noted, "U.S. retail sales of plant-based foods have increased by 11 percent… [in 2019], making it [a] $4.5 billion industry," citing a report published in July 2019 by the Plant-Based Food Association working with the Good Food Institute. In addition, a December 2019 study by Brigham and Women's Hospital, a teaching hospital of Harvard Medical School, found that moving to healthy diets could save more than $50 billion in U.S. health care costs.
There are several simple ways we can start the journey together: Implementing Meat Free Mondays, cutting red meat from our diets and finally giving up on fast food and ultra-processed foods. The road to a better, healthier future for all of us, and the planet, really does start with what we eat.