Why are ultra-processed foods so bad? What health effects can they have?
In his book Ultra-Processed People, Chris van Tulleken explains the negative health effects of ultra-processed foods. He goes over the host of diseases and illnesses that are linked to eating UPFs too often.
Here’s a look at why you should think twice about the foods you eat.
The Negative Health Effects of Ultra-Processed Food
Why are ultra-processed foods bad for you? Van Tulleken says UPF is not only unhealthy, it’s also unsafe, capable of leading to serious illness and even death. In this section, we’ll first explore UPF’s links to a variety of diseases, including obesity. Then, we’ll examine van Tulleken’s contention that lack of willpower and inactivity aren’t responsible for obesity—which leaves UPF as the primary culprit.
UPF Is Linked to a Host of Diseases and Illnesses, Including Obesity
There is a large body of research demonstrating that UPF increases the rates of many forms of disease and illness, including cancer, heart attacks and strokes, type 2 diabetes, weight gain and obesity, mental illness, dementia, and early death. Studies have indicated that it’s the processing of UPF that causes these health problems, rather than simply the nutritional content. Van Tulleken focuses on weight gain and obesity because there are more studies of UPF’s effects on weight.
(Shortform note: Because van Tulleken focuses on obesity, he doesn’t devote much time to explaining how UPF leads to other diseases. While the science in this area is still developing, some studies do address these causal mechanisms. For example, studies show that excess UPF consumption contributes to type 2 diabetes by raising blood sugar levels, leading to insulin resistance. Processed meat and UPF-containing refined carbohydrates, in particular, lead to an increased risk of type 2 diabetes.)
Widespread obesity didn’t exist for much of human history, writes van Tulleken. Until the beginning of the 20th century, obesity was very rare, especially in children. Since the 1970s, however, obesity has skyrocketed, and it affects more children than ever. Not coincidentally, we also began eating increasing amounts of UPF in the 1950s.
(Shortform note: Scientists often refer to the precipitous rise in obesity throughout the Western world since the 1970s as an “obesity epidemic.” In 1976, the prevalence of obesity in American adults was 15%; by 2000, that number had doubled to 30.9%. As of 2020, it was 40.9%. Worldwide obesity more than doubled between 1990 and 2022. In American children, obesity rates have tripled over the last three decades; one out of every six kids is obese. Doctors generally screen for obesity using Body Mass Index (BMI), which is weight in kilograms divided by the square of height in meters. A BMI of 30 or higher is considered obese. However, BMI merely helps evaluate possible risks; it’s not a diagnosis of an individual’s actual health status.)
Experts had long thought that the reason obesity wasn’t a problem until recently was historical food scarcity, often resulting from famines and food shortages. However, more and more studies now demonstrate that UPF is probably the primary cause of the global increase in obesity. One study showed that people on a primarily UPF diet consumed an average of 500 calories more per day (and gained weight accordingly) than people on a non-UPF diet, even though both diets contained identical amounts of fat, salt, sugar, and fiber. The people on the non-UPF diet actually lost weight.
(Shortform note: While van Tulleken says that UPF leads to various serious diseases, including obesity, he doesn’t explain what makes obesity unhealthy on its own. Studies have consistently demonstrated that obesity increases the risk of diabetes, heart disease, arthritis, depression, and some cancers. But newer research also indicates that just because someone is overweight or obese, doesn’t necessarily mean they’re unhealthy. These studies show that people with too much visceral fat—fat located deep in the abdomen—have a higher risk of health problems. But excess subcutaneous fat—fat under the skin of the thighs, arms, and back—may promote good health. In short, some people are resistant to the negative effects of obesity. Scientists are still studying exactly why this is.)
Why Lack of Willpower and Inactivity Aren’t Responsible for Obesity
Many people believe that obesity is caused by a lack of willpower or a failure to exercise. According to van Tulleken, these beliefs are unfounded. Rather, obesity is caused by a genetic predisposition combined with an environment that triggers overeating. That environment, says van Tulleken, is the one created by UPF and UPF marketing, both of which are designed to get people to eat as much as possible.
Van Tulleken explains that everyone with obesity has a genetic predisposition to it, but not everyone with a genetic predisposition is obese. The difference is environment: specifically, the environment of UPF and poverty. Poor, urban areas are often characterized by an abundance of fast food restaurants, fast food advertising, and stores selling mostly UPF but very little fresh, minimally processed food. In addition, research shows that all stress, but especially the chronic stress caused by poverty, causes us to secrete a lot more of the hormone cortisol, which increases appetite and causes us to eat more.
People with a genetic predisposition to obesity who are surrounded by UPF and UPF marketing are therefore more likely to eat more UPF, regardless of their willpower.
Van Tulleken also claims that, despite the many studies reaching a contrary finding, obesity is not caused by inactivity. Studies show that people burn the same number of calories per day (about 2,500) whether they live in a rural hunter-gatherer society or an urban, more sedentary one. In other words, we can’t lose weight simply by being more active: Whether we exercise every day or sit at home reading a book, the amount of calories we burn is the same.
This is because when we burn calories through exercise, our body compensates by using less energy on routine bodily functions (for example, our immune, endocrine, or stress systems), so our total energy use stays the same. This allows some of our body’s systems to rest and recuperate. On the other hand, if we sit at a desk all day and are inactive, we use our excess energy on things like being stressed.
Why do so many people believe that exercise results in weight loss and inactivity results in weight gain? Van Tulleken suggests that it’s because the ultra-processed food industry has heavily funded many of the studies that supposedly demonstrate this. For example, Coca-Cola has provided millions in funding to hundreds of research projects finding that inactivity—not sugary sodas—causes obesity. Van Tulleken points out that industry-sponsored studies of sugar-sweetened beverages and weight gain are five times more likely than independent studies to reach conclusions favorable to the industry.
Van Tulleken argues that we’re eating more than we ever have (specifically, more UPF), and that’s what’s causing obesity—not failure to exercise or lack of willpower.
