A new study published last week in the journal Obesity pointed to a rising health concern fuelled by processed foods: protein hunger. This is when low-nutrient foods build up a “hunger” for protein, thereby prompting people to eat more. The study then identifies processed foods as the leading contributor to rising obesity in the Western world.

The researchers based their work around a concept known as the Protein Leverage Hypothesis. It was first theorized in 2005 by nutrition scientists David Raubenheimer and Stephen J Simpson, both of whom are also among the co-authors in the current study. The hypothesis argues that people often end up consuming more food in order to meet their bodies’ demand for protein. Since most processed foods are composed of sugars and other carbohydrates and contain very low protein, one has to consume them in higher numbers to satisfy their protein needs. “It’s increasingly clear that our bodies eat to satisfy a protein target. But the problem is that the food in Western diets contains increasingly less protein. So, you have to consume more of it to reach your protein target, which effectively elevates your daily energy intake.” Raubenheimer said in a press release.

This isn’t the first time scientists have cautioned against the increasing ubiquity of processed foods. Processed foods may be linked to dementia. Moreover, ultra-processed foods and drinks are today much sweeter — and more harmful — than they were a decade ago. The current study, then, reinforces the existing cautions against processed foods.

For their research, the Australia-based scientists analyzed data from the country’s National Nutrition and Physical Activity Survey, a year-long study of close to 10,000 individuals. The mean age of the sample size was 46.3 years. The scientists observed that protein only made up 18.4% of the population’s mean energy intake. On the other hand, carbohydrates contributed to almost half of the number, at 43.5%. Energy from fat made up 30.9%. Fibre made up only 2.2% of the total mean energy intake, while alcohol contributed to 4.3%. The scientists also observed that those who consumed less protein in their first meal of the day ended up increasing their overall food intake levels in their following meals. Those who received an adequate share of protein in the first meal, on the other hand, did not. In many cases, in fact, they reduced their intake in the rest of the meals.

Related on The Swaddle:

Social Stigma Plays a Role in How Obesity Meets Depression, Study Shows

Further, those in the survey with a lower proportion of protein in the first meal consumed more processed foods — energy-dense foods high in saturated fats, sugars, and salt — throughout the day, and less of grains, vegetables, legumes, fruit, dairy, and meats. This led to them having a protein-deficient diet in each meal, which in turn only boosted their intake of processed foods further. In other words, this caused a “protein dilution” in their diets. “Humans, like many other species, have a stronger appetite for protein than for the main energy-providing nutrients of fats and carbohydrates. That means that if the protein in our diet is diluted with fats and carbohydrates, we will eat more energy to get the protein that our bodies crave,” Raubenheimer explained in the press release.

The current study focuses on obesity in the developed, Western world. But nutrient-deficient processed foods may also be a big factor in rising obesity in the developing world of lower-and-middle income countries. The World Health Organization on its website describes how several countries in the lower-and-middle income group are suffering from a “double burden” of obesity as well as malnutrition. A prime example of this situation is perhaps the town of Chiapas in Mexico, which is reeling under a Coca-Cola epidemic. Chiapas is located in Mexico’s poorest state. “Protein hunger”, in such a scenario, may be able to explain the nutritional causes behind this “double burden.”

The protein hunger concept can thus provide an important framework for tackling the problem of obesity. Previous studies have also noted the role of protein in morning meals in controlling hunger and cravings. Identifying processed foods for being responsible, further, is an important step to urge people to move to healthier diets. A 2020 study predicts that by 2050, the rising demand for processed foods would worsen both global obesity and malnutrition.

There’s thus a social justice issue at play: overwhelmingly, low-income countries find that healthy food is more expensive to come by. This means that processed food — and its effects — are more accessible than healthy food, and disproportionately accrued to a vulnerable population.

Social conditions therefore lead to the overconsumption of foods and drinks. In Chiapas, for instance, Coca-Cola costs as much as water, which is increasingly becoming scarce (at least partly, of course, due to the manufacture of Coca-Cola itself). It is thus necessary to understand the conditions consumerist capitalism creates that present consumption of ultra-processed food as the easier, more preferred alternative to unprocessed, nutrient-diverse food.