Researchers have said that an enhanced inflammatory response could be the key link between high saturated fat intake and the development of diseases like Type 2 diabetes and atherosclerosis.
"Obesity and an unhealthy diet can increase the risk of atherosclerosis, Type 2 diabetes and Alzheimer's disease but not in everyone," said lead author C Lawrence Kien from University of Vermont (UVM).
Inflammation, which involves the release of chemicals called cytokines from cells, is a normal part of the immune system's defense against infection.
Kien had a hunch that the pro-inflammatory effect of saturated fat might be facilitating how saturated fat impacts the risk of metabolic disease.
In their latest study, Kien and colleagues studied palmitic acid -- the most prevalent saturated fat in the diet.
They found that a high palmitic acid diet increased the concentration of several inflammatory biomarkers in both blood and muscle.
In a separate study, the team reported the same diet was associated with a reversible decrease in daily physical activity and increased anger, suggesting that a diet high in saturated fats may interfere with normal cognitive processes.
Relative to the low palmitic acid diet, the high palmitic acid diet stimulated the production of cytokines, thus creating more inflammation and associated risk for metabolic disease.
"It is important to acknowledge that other factors -- for example, physical activity -- and other features of complex diets will determine how persistent, high intake of saturated fat will impact health," Kien reported.
Eating Mediterranean-type diet -- with low-saturated fat -- appears to decrease the inflammatory response both in comparison to a high-saturated fat diet as well as in relation to a low-fat diet, the team reported.
The study appeared in the Journal of Nutritional Biochemistry