What is a major source of dietary fiber?

Whole grains are a major source of dietary fiber because they contain the entire grain kernel, which includes the bran, germ, and endosperm. The bran layer is particularly high in insoluble fiber, which adds bulk to the diet and aids in digestion by helping to prevent constipation and promote regularity. Whole grains, such as brown rice, barley, oats, and whole wheat products, are recognized for their health benefits, including supporting heart health, maintaining a healthy weight, and improving gut health.

In contrast, red meat typically contains no dietary fiber, while processed snacks often contain refined grains that lack fiber due to the removal of the bran and germ during processing. Dairy products also do not provide a significant amount of fiber, as they are primarily sources of protein and calcium. Therefore, whole grains stand out as the primary and beneficial source of dietary fiber in the diet.