For many years, people have been warned to stay away from processed foods, especially those that contain industrially made fats. These fats are often blamed for heart disease, weight gain, and other health problems.
As a result, many people believe that any fat created or changed by food factories must be harmful. However, new research suggests that this belief may be too simple and that not all processed fats are equally bad for heart health.
A new study led by scientists from King’s College London and Maastricht University looked closely at two common types of hard fats used in everyday foods.
These fats are often found in baked goods, margarines, spreads, pastries, and many packaged products people eat regularly. The researchers wanted to understand whether these fats actually harm the heart when eaten in realistic amounts.
The fats studied are called interesterified fats. These fats are created through a food processing method that changes the structure of oils to make them solid at room temperature.
This process is widely used by the food industry because it allows manufacturers to replace trans fats, which are known to increase the risk of heart disease. Interesterified fats also help improve the texture, taste, and shelf life of foods.
In this study, researchers focused on two kinds of interesterified fats. One was rich in palmitic acid, which mainly comes from palm oil. The other was rich in stearic acid, which comes from other plant-based oils. Both types are commonly used in food products sold in supermarkets.
To test their effects, the researchers ran a carefully designed clinical trial involving forty-seven healthy adults. The study used a double-blind crossover design, which means that neither the participants nor the researchers knew which fat was being consumed at any given time. This helps prevent bias and makes the results more reliable.
Each participant followed two different diets, each lasting six weeks. During one phase, they ate foods made with palmitic acid-rich fats. During the other phase, they consumed foods made with stearic acid-rich fats.
The diets included muffins and spreads designed to provide about ten percent of daily energy intake from these fats. This amount reflects what people could realistically consume in their normal diets.
Throughout the study, researchers carefully measured many signs of heart and metabolic health. These included cholesterol levels, triglycerides, insulin sensitivity, inflammation in the body, liver fat, and how well blood vessels functioned. These markers are commonly used to assess the risk of heart disease and related conditions.
The results were reassuring. The researchers found no meaningful differences between the two types of fats in terms of cholesterol levels or triglycerides. Importantly, the balance between total cholesterol and “good” HDL cholesterol did not worsen. This ratio is considered an important indicator of heart disease risk.
The study also found no negative effects on inflammation, blood sugar control, liver fat levels, or blood vessel health. In other words, consuming these interesterified fats for six weeks did not increase short-term risk factors linked to heart disease.
Professor Sarah Berry, one of the senior researchers, explained that this study challenges the idea that all food processing is harmful.
She pointed out that interesterification allows food companies to create solid fats without using trans fats, which are clearly linked to heart problems. This process can also help reduce the total amount of saturated fat in some foods.
The lead author, Professor Wendy Hall, added that these findings are important because these fats are already widely used in everyday foods. The study suggests that when eaten in realistic amounts, both palmitic acid-rich and stearic acid-rich interesterified fats are unlikely to damage heart health in the short term.
While the study lasted six weeks, this length of time is considered enough to detect meaningful changes in cholesterol and other heart-related markers. Still, the researchers noted that longer studies are needed to understand the effects of consuming these fats over many years.
When reviewing and analyzing these findings, it becomes clear that the results offer a more balanced view of processed fats. The study does not suggest that people should eat more processed foods, but it does show that some industrially processed fats may be safer than previously believed.
It also highlights the importance of judging foods based on scientific evidence rather than fear. Overall, the research supports the idea that replacing harmful trans fats with carefully designed alternatives can be a positive step for public health, especially when consumption stays within realistic limits.
If you care about heart health, please read studies that apple juice could benefit your heart health, and Yogurt may help lower the death risks in heart disease.
For more information about health, please see recent studies that Vitamin D deficiency can increase heart disease risk, and results showing Zinc and vitamin B6 linked to lower death risk in heart disease.
The study is published in The American Journal of Clinical Nutrition.
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