New research provides additional evidence that consumption of ultra-processed foods is driving the obesity epidemic, causing people to overeat in response to their bodies’ strong cravings for protein.
Study Confirms Processed Food Is Key To Rising Obesity
Large population studies have shown that “protein starvation” promotes overeating.
A year-long study of the diets of 9,341 Australians adds to the evidence that highly processed and refined foods are a major contributor to rising obesity rates in Western countries.
The new study, based on a national nutrition and physical activity survey conducted by the Australian Bureau of Statistics (ABS), further supports the “protein utilization hypothesis.” It was conducted by the Charles Perkins Center (CPC) at the University of Sydney and was published in the latest issue of the journal. obesity.
Protein Leverage Hypothesis, first proposed by Prof. Raubenheimer and Prof. Stephen Simpson in 2005, states that people overeat fats and carbohydrates because of a strong craving for protein, which the body actively prefers over everything else. Because much of the modern diet consists of highly processed and refined foods (low in protein), people tend to eat more energy-dense foods until they meet their protein needs. are driven to consume
David Raubenheimer (right) at work at the Annapurna Conservation Reserve in Nepal. Credit: David Raubenheimer
Processed foods lack protein and whet your appetite
“As people consume more junk food and highly processed and refined foods, the protein in their diet becomes scarcer, increasing their risk of being overweight and obese, which increases their risk of chronic disease. Research Fellow, CPC and the University’s School of Life and Environmental Sciences.
“It’s becoming increasingly clear that our bodies eat to meet their protein goals,” added Professor David Laubenheimer, Leonard Ullmann Professor of Nutritional Ecology at the School of Life and Environmental Sciences. “The problem, however, is that Western diets are getting less and less protein. Effectively increases intake.
“Humans, like many other species, have a stronger need for protein than for fat and carbohydrate, the main nutrients that provide energy. If it’s diluted, you’ll be eating more energy to get the protein your body craves.
Researcher at the Charles Perkins Centre, University of Sydney.Credit: University of Sydney
protein essential for health
Proteins are the building blocks of life. All cells in the body contain proteins that are used to repair cells and create new cells. And it’s estimated that over one million forms of protein are required for the human body to function. Protein sources include meat, milk, fish, eggs, soybeans, legumes, beans, and grains such as wheat germ and quinoa.
Scientists at the University of Sydney used data from a cross-sectional survey on nutrition and physical activity of 9,341 adults, known as the National Nutrition and Physical Activity Survey, conducted between May 2011 and June 2012, with an average age of 46.3 years. was analyzed. People’s average energy intake is 8,671 kilojoules (kJ), and the average percentage of energy from protein is only 18.4%, compared to 43.5% from carbohydrates, 30.9% from fat, and only 2.2 from fiber. % and 4.3% from textiles. alcohol.
We then plotted the relationship between energy intake and time spent and found that the pattern matched that predicted by the protein utilization hypothesis. Those who ate less protein at the first meal of the day increased their overall food intake at subsequent meals, whereas those who ate the recommended amount of protein did not, and actually Reduced food intake through
Professor Stephen Simpson, Academic Director, Charles Perkins Centre, University of Sydney, said:Credit: University of Sydney
It turns out that ‘protein starvation’ promotes overeating
They also found statistically significant differences between groups by the third meal of the day. The group that started the day with a higher percentage of energy from protein had a much lower total energy intake for the day. On the other hand, those who ate less protein foods at the beginning of the day increased their consumption, indicating that they were trying to compensate by increasing their overall energy expenditure. This is despite the fact that they were the smallest in the group, had the lowest energy and food consumption, and had the largest last meal.
Participants with a lower percentage of protein than recommended in their first meal consumed more of any food (energy-dense food high in saturated fat, sugar, salt, or alcohol) throughout the day and Eat less of the five recommended food groups (cereals, vegetables). / legumes; fruit; dairy and meat). The result was an overall worsening of the diet with each meal and a decrease in the protein-energy fraction even as ad libitum food intake increased. Scientists call this “protein dilution.”
David Raubenheimer with hunter-gatherers in the Congo Basin. Credit: David Raubenheimer
Effects seen in other studies
Professor Raubenheimer and colleagues confirmed this effect over a decade ago in other studies, including randomized controlled trials.
“The problem with randomized controlled trials is that diet is treated as a disease when it is not,” says Dr. Grech. “Laboratory studies may not show what people are actually eating or doing on a population level. And at the population level, it has been confirmed that as the percentage of energy from protein in the diet increases, people eat less fat and carbohydrates.
Many factors contribute to excessive weight gain, including dietary patterns, physical activity levels, and sleep habits, but scientists at the University of Sydney found that the body’s strong demand for protein and highly processed and refined foods lack of is an important driver of energy. Overconsumption and Obesity in the Western World.
Obesity explained
“This result supports the integrated ecology of obesity that low-protein, highly processed foods lead to higher energy intake in response to a nutritional imbalance caused by a predominant appetite for protein.” and support the explanation of the mechanism,” said Professor Raubenheimer. “This supports the central role of protein in the obesity epidemic and has important implications for global health.”
In an attempt to understand how protein enhances human nutrition, I brought in Professor Laubenheimer to study the diets of people in the furthest places from the Congo to the Himalayas. The protein mechanism is a revolutionary insight,” he said. “Obesity, diabetes, cardiovascular disease – these are all caused by diet, and we need to use what we have learned to control them.”
The CPC team’s research obesity Research leader Professor Raubenheimer was invited to speak at the annual Obesity Journal Symposium in San Diego on November 4th.
References: “Macronutrients (Imbalance) Promote Energy Intake in Obesity-Inducing Food Environments: An Ecological Analysis”, Amanda Greck, Zixian Sui, Anna Langan, Steven J. Simpson, Sean CP Coogan, David Laubenheimer, 2 November 2022, obesity.
DOI: 10.1002/oby.23578
