Which statement best describes the impact of dietary fiber on disease risk and weight management?

• A. Fiber has no impact beyond GI.
• B. Fiber reduces energy expenditure.
• C. Fiber lowers risk of cardiovascular disease, type 2 diabetes, and some cancers and aids weight management.
• D. Fiber causes dehydration.

Answer: (C)

Dietary fiber influences health beyond digestion by shaping how the body handles fats, sugars, and body weight. Fiber, especially the soluble kind, can help lower LDL cholesterol by binding bile acids in the gut, which nudges the body to use more cholesterol to make new bile. It also slows the rise in blood glucose after meals, improving insulin response and reducing the risk of type 2 diabetes. The bulk and slower gastric emptying from fiber increase feelings of fullness, which often leads to lower overall energy intake and supports weight management. In the gut, fermentation of fiber produces short-chain fatty acids that can positively affect metabolism and appetite regulation. These combined effects contribute to lower risk of cardiovascular disease, type 2 diabetes, and some cancers, making fiber a beneficial factor for both disease risk reduction and weight control. It’s not limited to gastrointestinal effects, and it doesn’t inherently cause dehydration—adequate fluids help fiber move through the digestive system, especially when fiber intake is higher.