A new meta-analysis conducted by the University of Washington indicates that no amount of processed food is considered safe for consumption.
The research team reviewed 77 studies to examine the relationship between processed food intake and the development of common chronic illnesses.
“Regularly consuming even small amounts of processed meats, sugary beverages, and trans fats is associated with a heightened risk of type 2 diabetes, ischemic heart disease, and colorectal cancer,” said lead author Demewoz Haile, a research scientist at the Institute for Health Metrics and Evaluation, in an interview with Fox News Digital.
“There is no safe threshold for routinely consuming these food groups, and they should be excluded from our daily diets,” he added.
Specifically, the researchers found that consuming just 0.6 to 57 grams of processed meat per day was linked to an 11% increase in the risk of developing type 2 diabetes.
Similarly, eating between 0.78 and 55 grams daily was associated with a 7% higher risk of colorectal cancer.
For reference, a single hot dog—composed almost entirely of processed meat—contains roughly 50 grams.
The researchers also examined the effects of sugar-sweetened beverages, finding that consuming between 1.5 and 390 grams per day was linked to an 8% higher risk of developing type 2 diabetes.
Drinking up to 365 grams daily was associated with a 2% increase in the risk of ischemic heart disease—the most common form of heart disease and a leading cause of death.
The study also assessed the impact of trans fatty acids. When these unsaturated fats made up 0.25% to 2.56% of daily caloric intake, they were associated with a 3% greater risk of ischemic heart disease.
Examples of foods that may contain trans fats include crackers, cookies, baked goods, frozen pizza, coffee creamers, refrigerated dough products, vegetable shortenings, and certain stick margarines, according to WebMD. Some fast foods are also sources of trans fats.
The study’s findings were published in the journal Nature Medicine on June 30.
While earlier research has already linked processed foods to chronic illnesses, lead author Demewoz Haile noted that this new analysis takes a more advanced approach.
“Our study examined the shape of the relationship using the latest data and more sophisticated analytical methods, providing an objective assessment of the strength of the evidence,” Haile explained.
He added, “We found that the strongest associations appeared even at low levels of consumption—equivalent to a single serving or less—suggesting that any regular intake of these foods may raise the risk of negative health outcomes.”
Although the researchers acknowledged that diet is a personal decision and that food choices may be limited for some individuals, they recommend reducing or eliminating processed food consumption whenever possible.
“Our findings align with existing recommendations from organizations like the WHO and CDC: minimize or avoid the consumption of processed meats, sugary drinks, and artificial trans fats,” Haile told Fox News Digital.
He added, “People who regularly eat these foods, even in small amounts, should be aware of their heightened risk for chronic diseases.”
Potential limitations
Haile noted that a key limitation of the study relates to how dietary intake was measured.
“Nearly all the studies included relied on food frequency questionnaires, which can introduce measurement errors because participants may have difficulty accurately recalling their long-term eating habits,” he explained to Fox News Digital.
Regarding processed meats, the researchers found that consuming as little as 0.6 to 57 grams daily was linked to an 11% increased risk of developing type 2 diabetes.
Several studies included in the analysis only assessed participants’ consumption at the beginning of the study, Haile noted, “which might not accurately reflect their dietary habits over time.”
Additionally, the study focused on a limited number of health outcomes for each dietary risk factor.
“As a result, our findings may underestimate the total health impact of these foods,” Haile said.
“We also found considerable variation across existing research, highlighting the need for more high-quality studies to strengthen the evidence and reduce uncertainty.”
Experts highlight caveats
Dr. Nick Norwitz, M.D., PhD, a Harvard-trained clinical researcher and metabolic health educator, acknowledged that the study demonstrates a “relatively consistent association” between higher processed meat intake and negative health outcomes but pointed out some important caveats.
“These are associations, not definitive causal relationships,” Norwitz, who was not involved in the study, told Fox News Digital.
He also noted that the researchers themselves graded the quality of the evidence as “weak.”
The study found that consuming between 0.78 and 55 grams of processed meat per day was linked to a 7% increase in colorectal cancer risk.
“While these large studies have strengths, one significant limitation is that they group many different foods into broad categories,” Norwitz explained. “There are multiple methods of processing meat, and not all have the same biological effects.”
Though it is “certainly plausible” that processed meat contributes to poor health outcomes, Norwitz emphasized that further research is needed to confirm the findings of this meta-analysis.
“At the end of the day, something like the office donut or a bottle of soda is likely causing more metabolic harm than a slice of deli turkey,” he added.
A spokesperson for the American Association of Meat Processors (AAMP) issued the following statement to Fox News Digital regarding the study:
“We have not reviewed the full report, but the paper’s abstract notes that the findings reflect ‘weak relationships or inconsistent input evidence,’ and that further research is needed. We would also like clarification on how the study defined ‘processed meat’ and whether the researchers considered the proven nutritional benefits and protein content of meat alongside any potential risks.”
In the study, processed meat was defined as “any meat preserved by smoking, curing, salting, or the addition of chemical preservatives.”
Fox News Digital also contacted the Academy of Nutrition and Dietetics and the U.S. Department of Agriculture (USDA) for their comments.
