It’s been known for some time that ingesting saturated fats, especially from non-plant sources, can adversely impact one’s health. Researchers at Wageningen University in the Netherlands studied the impact of trans fatty acids (TFAs) on blood vessel health. They wanted to investigate whether different diets affect the blood vessels' ability to dilate or expand; namely a comparison of a diet high in TFAs (9.2 percent of fats ingested were TFAs) versus one in which saturated fats replaced the TFAs. (Takeaway? TFAs are even more lethal than animal-derived saturated fats.) According to Nicole M. de Roos, M.Sc., a Ph.D. fellow and lead author of the study, although trans fats typically make up a relatively small portion of total fat ingested, it can have a huge impact on disease risk. They found that the ability of the blood vessels to dilate was 29 percent lower in people who ate the high-TFA diet compared those on the saturated fat diet. Blood levels of HDL cholesterol were 21 percent lower in the TFA group compared to the saturated fat group. Bottom line? Avoid TFAs. Lower your intake of animal-derived saturated fats. Use healthier fats in moderation (e.g., cold-pressed olive oil, coconut oil, avocados).