Eating oatmeal for just two days can significantly lower cholesterol levels, a new clinical trial from the University of Bonn has found. The study, published in Nature Communications, focused on individuals with metabolic syndrome – a condition linked to increased risk of diabetes and heart disease – but without existing diabetes.
During the trial, 32 participants followed a strict 48-hour diet consisting solely of boiled oatmeal three times daily, with limited additions of fruits or vegetables. Each participant consumed approximately 300 grams of oatmeal daily, reducing their usual caloric intake by about 50 percent. A control group followed the same calorie restriction but without the inclusion of oats.
Results indicated that the oat-based diet led to a more substantial reduction in cholesterol levels than calorie restriction alone. After 48 hours, participants in the oat group experienced an average decrease of 8 percent in total cholesterol, and a 10 percent reduction in LDL, or “bad” cholesterol, according to the study. Participants also experienced modest weight loss and reductions in blood pressure.
Researchers analyzed stool and blood samples to understand the mechanisms behind these improvements. They discovered that oat consumption increased the presence of specific gut bacteria known to produce phenolic compounds, which are associated with improved cholesterol metabolism. “We were able to identify that the consumption of oatmeal increased the number of certain bacteria in the gut,” explained lead author Linda Klümpen. “For instance, we were able to show that intestinal bacteria produce phenolic compounds by breaking down the oats.”
The team further investigated dihydroferulic acid, a compound created when gut bacteria metabolize oats. Findings suggest this compound may contribute to reducing cholesterol storage within the body. Previous animal studies have indicated that ferulic acid, another compound produced during oat breakdown, also positively impacts cholesterol metabolism.
A secondary phase of the research involved 17 volunteers consuming 80 grams of oats daily for six weeks, without significant dietary changes. Another 17 participants served as a control group, avoiding oats. While this longer-term oat consumption showed some health benefits, it did not replicate the rapid cholesterol reduction observed in the strict two-day diet.
The study suggests that even a short-term, oat-focused diet, combined with reduced calorie intake, can improve cholesterol levels. Recent reporting from ScienceDaily and SciTechDaily confirms the findings, noting the potential for a 10% reduction in bad cholesterol with a two-day oatmeal diet. News-Medical also reported on the rapid cholesterol reduction potential of increased oat consumption.