The beta-glucans found in cereals are the most thoroughly researched type, and their benefits appear similar to other kinds of soluble dietary fiber.
In people with dyslipidemia, beta-glucans from oats or barley may provide small reductions in LDL cholesterol and total cholesterol.[1][2][3] These beta-glucans also promote satiety and are linked to a small degree of weight loss.[4]
When included in a carbohydrate-containing meal, beta-glucans from oats and barley may lower the postmeal increase in blood glucose and insulin.[4] Although reductions in fasting blood glucose and hemoglobin A1c (HbA1c) have been reported in people with type 2 diabetes, these effects have tended to be small enough that their clinical relevance is questionable.[5]