Human randomized trials · January 2026
Oats, microbes, and cholesterol
Two small trials assigned 68 adults with metabolic syndrome—a cluster of risk factors such as high blood pressure and abnormal blood fats—to oat diets or comparison diets. A two-day, high-oat diet lowered LDL cholesterol, while the six-week, moderate-oat diet did not show the same cholesterol benefit. Changes in compounds made from oats by gut microbes suggest a possible part of the explanation.
Why it's interesting: researchers are moving beyond asking which bacteria are present to asking what those bacteria make from our food.
What remains uncertain: these were small, specific groups, and the microbial mechanism isn't fully established. Cholesterol changes don't demonstrate better bowel habits. This isn't a reason to copy an intensive oat diet.
Read the open-access study · Nature Communications ↗