Eating a meal with “good” fat provides health benefits, but going through a stressful event during the day can eradicate all that, a team of scientists discovered.

Researchers from Ohio State University investigated the relationship between diet, stress and inflammatory markers. As an offshoot of a parent study that looks into the link between high-fat diet and depression in cancer survivors, the new study sought to determine how daily stressors affect inflammatory responses to meals with “bad” fat.

Fat is an essential component of a healthy diet. However, there are two kinds of fat.

According to the American Heart Association, “good” fats, or monounsaturated and polyunsaturated fats, are generally those that come from fish, vegetable oils and nuts. They stay liquid at room temperature. On the other hand, “bad” fats, or saturated and trans fats, tend to stay solid at room temperature. They increase the amount of cholesterol in the body.

To determine how stress and diet affect inflammatory markers, the researchers recruited 58 women for the study, 38 of whom were cancer survivors. The women’s average age was 53.

The women went to Ohio State University on two separate occasions and were given either of two meals, which they consumed within 20 minutes.

The first meal, composed of biscuits and gravy and served along with eggs and turkey sausage, was prepared mostly with saturated fat. The second meal was identical to the first, except that it was prepared with monounsaturated sunflower oil.

The meals were made to mimic a high-fat, high-calorie fast food meal that typically has more than 900 calories and 60 grams of fat.

To see if the women experienced stress, they were made to answer the Daily Inventory of Stressful Events questionnaire. Minor irritants were ruled out as stressors, but bigger ones, like cleaning up paint spilled by a child, counted as a stressor.

As lead study author Jan Kiecolt-Glaser described, the stressors were “not life-shattering events, but they're not of the hangnail variety either.”

Blood samples were also collected from the study participants.

The researchers found that those who ate the food prepared with “bad” fat showed high levels of inflammatory markers, while those who ate food with “good” fat had lower levels of the markers.

However, this difference disappeared in women who reported having a stressful day; the results were the same for those who ate the meal with saturated fat and those who ate the meal with sunflower oil.

On the other hand, stress did not raise the level of inflammatory markers further for those who ate food with saturated fat.

"It's more evidence that stress matters," Kiecolt-Glaser said.

The study authors emphasized that their results do not mean people can eat whatever they want when they are stressed. The study should serve as a reminder to opt for healthier food every day so that one’s health is in a better condition should stress hit.

“These data show how recent stressors and an MDD history can reverberate through metabolic alterations, promoting inflammatory and atherogenic responses,” the study authors concluded.

The study was published in the journal Molecular Psychiatry.