There are two types of fiber in the diet, soluble fiber (water-soluble) and insoluble fiber (not water-soluble). Whole foods such as fruits, vegetables, legumes, nuts, seeds and whole grains usually contain at least some of both soluble and insoluble fiber.
Soluble fiber is highest in foods such as oats, legumes, barley, pears, and apples. Higher amounts of insoluble fiber are found in wheat bran, whole grain breads and cereals, and most vegetables such as broccoli and carrots. There are many benefits to incorporating both kinds of fiber into your diet and helping with weight loss is one of them:
- Soluble fiber will decrease your appetite. It will form a gel inside your digestive tract making you feel full longer, and reducing the desire to consume extra calories between meals. Think of a sponge that has absorbed water filling up your digestive tract.
- Soluble fiber will slow absorption of carbohydrates, helping to keep your blood sugar more stable and preventing dips that may lead you to look for your next snack.
- Insoluble fiber is not digested so it cleans your digestive tract as it moves through it. Think of a scouring pad, which is coarser than the soluble fiber sponge, facilitating movement and keeping your digestive tract clean and healthy.
- Foods high in fiber are lower in calories (less energy dense) compared to more processed, refined foods.
Eating a diet high in both soluble and insoluble fiber contributes to weight loss by keeping you full longer, stabilizing your blood sugars, keeping your digestive tract clean, and reducing your calorie intake. For more information on fiber and weight loss, schedule an appointment with a nutritionist.
Wendy Caamano, MS, CN, dietetic intern, and Debra A. Boutin, MS, RD
chair and dietetic internship director, Department of Nutrition and Exercise Science at Bastyr University