The words “trans fat” often make people think of unhealthy fast food and packaged snacks. For years, health experts have warned that trans fats raise the risk of heart disease, and those warnings remain true for the industrial form found in partially hydrogenated oils.
However, a new scientific review shows that naturally occurring trans fats in dairy products tell a very different story.
Milk, yogurt, cheese, butter, and other dairy foods naturally contain small amounts of trans fats because they come from cows, sheep, and goats. These fats are produced naturally during digestion in the animals and are not created by food factories.
Researchers wanted to know whether these natural trans fats carry the same health risks as industrial ones. To investigate, they combined results from 22 previous studies involving thousands of participants from Europe, Canada, and the United States. Their findings were published in the journal Nutrition Research.
The scientists first examined 10 controlled clinical studies. In these experiments, volunteers consumed dairy products with naturally higher trans fat levels while researchers monitored changes in blood cholesterol and other markers linked to heart disease.
Even when people consumed relatively high amounts of natural dairy trans fats, the studies found no important changes in blood lipid levels compared with ordinary dairy products.
Next, the researchers reviewed 12 long-term population studies that followed participants for many years. These studies measured natural dairy trans fats in blood samples and tracked whether participants later developed heart disease, stroke, cardiovascular death, or type 2 diabetes.
Again, the researchers found no evidence that higher natural dairy trans fat levels increased the risk of any of these conditions.
According to Professor Ian Givens from the University of Reading, consumers often hear the term “trans fat” and assume every type is dangerous. This review shows that the source of the trans fat matters. Industrial trans fats remain harmful and should still be avoided whenever possible, but naturally occurring dairy trans fats do not appear to carry the same risks.
The findings may also help improve food labeling policies and public understanding. Many people have reduced dairy consumption because they believed all trans fats were equally unhealthy. This study suggests that such concerns may not be supported by current scientific evidence.
Even so, experts continue to recommend eating dairy products in reasonable amounts as part of an overall healthy eating pattern. No single food determines heart health. Regular exercise, avoiding smoking, controlling blood pressure, and eating a balanced diet remain the most important ways to lower cardiovascular risk.
By combining controlled dietary trials with large prospective cohort studies, the researchers examined both short-term biological effects and long-term disease outcomes. This combination strengthens confidence in the conclusions.
However, most of the evidence is observational, so further research could explore whether different dairy products or eating patterns influence results. Overall, the study provides reassuring evidence that natural dairy trans fats should not be confused with harmful industrial trans fats.
If you care about nutrition, please read studies that vitamin D can help reduce inflammation, and vitamin K may lower your heart disease risk by a third.
For more health information, please see recent studies about foods that could sharp your brain, and results showing cooking food in this way may raise your risk of blindness.
Source: University of Reading.
