It is well known that eating too many high-fat meals will clog arteries and increase heart attack risk.
But now comes the news that even a single high-fat meal can quickly send your blood pressure soaring.
And this immediate pumping up of blood pressure levels could provide a key mechanism through which high fat meals produce heart disease over time.
Researchers at the University of Calgary, Canada looked at the stress responses of 30 students broken into two groups and found that the group eating high-fat were more reactive to stress, recording greater reactivity in several cardiovascular measures, a report by Canadian Television said Monday.
Both groups fasted the night before and one group consumed a fast-food breakfast from McDonald's, the other ate dry cereal with skim milk, cereal bars and non-fat yogurt. Both meals contained the same number of calories. The low-fat breakfast included supplements to balance it for sodium and potassium.
Two hours after eating the breakfasts, the two groups were subjected to standard physical and mental stress tests, including a mathematical test designed to be stressful, a public speaking exercise and others, while having their cardiovascular responses measured.
The researchers then measured the subjects' blood pressure, heart rate and the resistance of blood vessels. "Regardless of the task, we recorded greater reactivity among those who consumed the high-fat meal in several cardiovascular measures we recorded," says Fabijana Jakulj, a University of Calgary student who used the study as the basis for her honors thesis.
Exaggerated or prolonged responses to stress are thought to predict the development of high blood pressure.
Dr. Tavis Campbell, a specialist in behavioral medicine and the study's senior author, says the study suggests a new and damaging way that a high-fat diet affects cardiovascular function. "What's really shocking is that this is just one meal," he says.
He also points out that the vast majority of high blood pressure cases have no known cause. And he speculates that prolonged and frequent exposure to fast food meals could provide an explanation for many of these.
He said further tests showed that the noted pressure jumps in his subjects were due to the constriction of veins and arteries in the body, which forces the heart to beat harder to circulate blood through.
Over time, Campbell says, the problem might become cumulative, with such vessel constriction becoming permanent after a steady influx of high fat foods.
The study is published this month in the Journal of Nutrition.