Are ultra-processed foods a public health hazard?

Yes, the scientific consensus increasingly says they are

A growing body of evidence—including major 2025 reviews—indicates that ultra-processed foods (UPFs) pose a genuine and significant public health risk.

The Evidence

Scale of the problem: In the U.S., UPF currently make up more than half of what U.S. adults eat on a daily basis, and two-thirds of what kids and teens eat. Similarly, they now account for approximately half of the caloric intake in many countries and notably by children.

Major scientific statements: A landmark three-paper series published in The Lancet in late 2025, authored by more than 40 global health experts, concluded that more than a hundred studies which have linked ultraprocessed foods to poor health outcomes, including an increased risk of Type 2 diabetes, obesity, chronic kidney and heart disease, even depression. As one of the lead authors, Barry Popkin of UNC, put it: "We can say now that truly ultraprocessed food represents a clear global threat to our health - not only our physical health but also mental health in terms of its impacts on depression."

Quantified risks: A comprehensive 2024 umbrella review of 45 meta-analyses covering nearly 10 million participants found "convincing" evidence that a diet high in ultra-processed foods increases the risk of death from cardiovascular disease by 50% and the risk of anxiety by 48%, and "highly suggestive" evidence that greater consumption of these foods increases the risk of death from heart disease by 66%, the risk of obesity by 55%, sleep disorders by 41%, Type 2 diabetes by 40%, early death from any cause by 21% and depression by 20%.

A separate large 2025 systematic review covering over 8 million people found that each additional 100 g/day of ultra-processed food consumption was associated with a 14.5% higher risk of hypertension, 5.9% increased risk of cardiovascular events, 1.2% increased risk of cancer, 19.5% higher risk of digestive diseases and 2.6% higher risk of all-cause mortality.

New colorectal cancer link: A 2025 Harvard study found that younger women eating more UPFs—including highly processed bread, breakfast food and soda, may be more likely to develop colorectal cancer.

Possible Mechanisms

Scientists are moving beyond pure association to identify causal pathways:

Important Caveats

The picture isn't entirely uniform. A 2024 umbrella review found weak to no evidence for many site-specific cancers, including breast, central nervous system, chronic lymphocytic leukemia, pancreatic and prostate cancer, as well as for conditions like hypertriglyceridemia, low HDL cholesterol levels, Crohn's disease, ulcerative colitis, hyperglycemia, metabolic syndrome and non-alcoholic fatty liver disease.

Additionally, not all UPFs are equal—some ultra-processed foods, such as whole-grain breads and yogurts, are associated with reduced risks of chronic diseases, including colorectal cancer. The NIH notes that studies show some UPFs may carry higher risks than others; knowledge gaps remain.

Policy Response

Despite the mounting evidence, regulatory action on their use has remained limited, with researchers pointing to increasing examples of inappropriate food industry influence on political decisions in several countries. The Lancet authors have explicitly called for governments to act, arguing that improving diets can't solely rely on consumer behavior change—it requires coordinated global policies to legislate reductions of ultraprocessed food production, marketing and consumption.

Bottom Line

While some scientific debate remains about specific mechanisms and which UPF subcategories carry the most risk, the overall weight of evidence—spanning large population studies, systematic reviews, and now some controlled trials—strongly supports treating heavy UPF consumption as a genuine public health hazard linked to chronic disease, mental health issues, and premature death. Major health bodies and researchers are increasingly calling for policy-level intervention rather than relying solely on individual choice.