One meal high in saturated fat can weaken concentration, according to a new study published in The American Journal of Clinical Nutrition.
Researchers revealed that eating a single meal high in saturated fat can lead to poor concentration. They examined how 51 women responded to a test of their attention after consuming either a meal high in saturated fat or the same meal cooked with sunflower oil, which is rich in unsaturated fat.
Results showed worse performance for women after eating a high-saturated-fat meal compared to when they ate the meal with a healthier fat. Hence, a link between that fatty food and the brain emerged.
The team, led by Annelise Madison, a graduate student in clinical psychology at The Ohio State University, studied the impact of leaky gut on concentration. Leaky gut happens when intestinal bacteria enter the bloodstream.
Findings revealed that participants with leakier guts had a worse performance in terms of the attention assessment regardless of the meal they had eaten.
The short attention span after a single meal was stunned the researchers.
"Most prior work looking at the causative effect of the diet has looked over a period of time. And this was just one meal -- it's pretty remarkable that we saw a difference," said Madison.
She also mentioned that the meal made with sunflower oil, while low in saturated fat, was rich in dietary fat.
"Because both meals were high-fat and potentially problematic, the high-saturated-fat meal's cognitive effect could be even greater if it were compared to a lower-fat meal," she said.
Continuous performance test
Madison, who works in the laboratory of Janice Kiecolt-Glaser, director of the Institute for Behavioral Medicine Research at Ohio State, ran a secondary analysis of data from Kiecolt-Glaser's study that examines whether high-fat meals led to fatigue and inflammation among former cancer patients.
The participants underwent a baseline assessment of their attention during a visit to the laboratory. The team applied a continuous performance test, which assesses sustained attention, concentration, and reaction time based on 10 minutes of computer-based activities.
The high-fat meal they ate had biscuits, turkey sausage, eggs, and gravy containing 60 grams of fat. This meal is either a palmitic acid-based oil high in saturated fat or the lower-saturated-fat sunflower oil.
Meanwhile, both meals had 930 calories and were served to imitate the contents of various fast-food meals like a Burger King double whopper with cheese or a McDonald's Big Mac and medium fries.
Endotoxemia
The fasting baseline blood samples of participants were also analyzed to see if they contained an inflammatory molecule that indicates the presence of endotoxemia.
Endotoxemia refers to the toxin that comes out of the intestines and goes into the bloodstream when something is wrong with the gut barrier.
"If the women had high levels of endotoxemia, it also wiped out the between-meal differences. They were performing poorly no matter what type of fat they ate," Madison said.
With this, Madison noted that previous research revealed the link between food high in saturated fat and inflammation throughout the body and possibly the brain.
"It could be that fatty acids are interacting with the brain directly. What it does show is the power of gut-related dysregulation," she said.
"What we know is that when people are more anxious, a good subset of us will find high-saturated-fat food more enticing than broccoli," she said. "We know from other research that depression and anxiety can interfere with concentration and attention as well. When we add that on top of the high-fat meal, we could expect the real-world effects to be even larger."
Madison's co-authors are Martha Belury, Rebecca Andridge, M. Rosie Shrout, Megan Renna, William Malarkey and Michael Bailey.
