Australian researchers have identified strong evidence linking ultra-processed foods to a range of serious health conditions, including weight gain, obesity, type 2 diabetes, heart disease, certain cancers, chronic inflammation, and depression. A major study published in The Lancet in 2025 analyzed the impact of these factory-made products on human health, with findings suggesting negative effects on the gut, heart, and brain.
Dr. Phillip Baker, an Associate Professor at The University of Sydney and co-lead author of the study, explained that ultra-processed foods, which became prevalent in supermarkets during the 1980s and 1990s, contain industrial ingredients not typically found in home kitchens. These include emulsifiers, gums, flavorings, colorings, modified starches, and protein isolates. These components, often in a "cocktail of additives," are engineered to make products more palatable and irresistible, leading to increased consumption.
"When you ultra-process a product, you're doing a lot of things to it. First of all, you're dehydrating the product, they tend to be lower in water content," Dr. Baker stated. "You're putting in more sugar, fat and modified starches but we also know that these products are designed to make them irresistible."
Emulsifiers, in particular, are a focus of concern, with emerging science suggesting they could potentially damage the gut lining, disrupt the microflora, contribute to a "leaky gut," and promote inflammation. Dr. Baker emphasized that the human body is not evolutionarily adapted to consume these highly processed foods and their ingredients in large quantities.
Australians are among the highest consumers of ultra-processed foods globally, with 40 to 50 percent of their daily calories derived from these products. Teenage boys and girls are particularly high consumers, with 70 to 80 percent of their diets potentially coming from ultra-processed sources. This trend is concerning due to the widespread availability of these foods, which now extend beyond obvious snacks and sugary drinks to items like bread, yogurt, and tofu that have undergone extreme processing.
One individual's experience highlights the potential personal impact. Danni Duncan, a fitness and nutrition coach described as "super fit and healthy," was diagnosed with bowel cancer at age 39. Despite having no family history of the disease, she experienced extreme fatigue and struggled with workouts shortly after the birth of her fourth child. Her surgeon suggested that childhood exposure to ultra-processed foods and chemicals may have contributed to her diagnosis.
"The doctor was talking about things like all the ultra-processed foods and chemicals that we were exposed to through the 90s and the early 2000s," Duncan said. "We were active kids who grew up on fruits and vegetables but we also had processed ham and cheese with white sandwich bread. In the '90s, there was this big influx of ultra-processed food because convenience was a thing."
Bowel cancer is a significant concern among young Australians, with cases surging in individuals under 50. In 2025, more than 14,780 Australians were diagnosed with colorectal cancer, and the disease claimed over 5,235 lives.
Further research into food additives, such as emulsifiers found in products like "Greek-style" yogurts, indicates they can also impact gut health. Professor Clare Collins, a dietitian and Professor of Nutrition and Dietetics at the University of Newcastle, explained that these additives can reach the large intestine and interact with gut bacteria, potentially disrupting the gut wall and leading to issues like leaky gut, allergies, and inflammatory bowel conditions. She advises consumers to consult official food additive lists if they wish to identify these ingredients, cautioning against unnecessary panic.