|Steak and French fries, a meal that is generally high in fat;|
a public domain photo by Petr Kratochvil
The researchers measured the levels of oxygen and carbon dioxide in the women's breath, which were related to their metabolic rate. They also performed blood tests to measure the women's glucose, triglyceride, insulin and cortisol levels. Glucose is also known as blood sugar and triglycerides are a type of fat. Insulin and cortisol are hormones. Insulin is released as a response to glucose in the blood and triggers glucose absorption by cells. Cortisol is a hormone released during stress. The tests on the women were performed regularly over a seven hour period.
The results of the tests showed that women who experienced one or more stressful events on the day before the fatty meal burned an average of 104 calories less than people who experienced no stress. They also had a temporarily increased level of insulin and triglycerides in their blood. Interestingly, these results were true whether the fat was saturated or monounsaturated, even though monounsaturated fats are generally considered to be much healthier than saturated fats.
The researchers say that the observed body changes could potentially lead to a weight gain of almost eleven pounds in a year. We already know that on their own stress and fatty meals are unhealthy; when the two factors occur in quick succession, they seem to be even worse for us! More tests need to be done, including tests in men to see whether the results are the same in them as in women.