April 25, 2007 -- Just one trip through the drive-through for a fatty, fast-food meal could put your heart at risk.
A new study shows eating a fatty meal heightens the unhealthy effects of stress on the heart, like raising blood pressure.
"What's really shocking is that this is just one meal," says researcher Tavis Campbell, PhD, assistant professor of psychology at the University of Calgary, in a news release. "It's been well documented that a high-fat diet leads to atherosclerosis [hardening of the arteries] and high blood pressure, and that exaggerated and prolonged cardiovascular responses to stress are associated with high blood pressure in the future."
"So when we learn that even a single, high-fat meal can make you more reactive to stress, it's cause for concern because it suggests a new and damaging way that a high-fat diet affects cardiovascular function."
Single Meal May Do Harm
In the study, 30 healthy adults fasted the night before and then ate either a high-fat breakfast from McDonald's consisting of a sausage McMuffin, an egg McMuffin, and two hash brown patties or a low-fat breakfast of dry cereal with skim milk, a cereal fruit bar, fat-free yogurt, and a glass of orange juice.
Both meals contained about 800 calories, but the high-fat meal had 42 grams of fat, and the low-fat meal had 1 gram of fat. A sodium supplement was added to the low-fat meal to even out the difference between the two meals.
Two hours later, the participants completed several stress-inducing tasks while researchers measured their cardiovascular response, including blood pressure, heart rate, and resistance within blood vessels. The tasks were designed to provoke mental and/or physical stress, such as completing a public speaking exercise about something emotionally provocative or holding a hand in ice water.
The results showed that regardless of the task, the blood pressure response was greater among those who ate the high-fat meal than those who ate the low-fat one.
Researchers say it's unclear how a single high-fat meal can sensitize the body to stress, but the results suggest a new way in which high-fat diets may contribute to heart disease.