What’s the difference between soluble and insoluble fibers?

If you've been hanging around the blog for awhile now, you know that fiber is one of the most important nutrients for health and disease prevention. It can get confusing when we begin to talk about the different forms of fiber and their distinctive effects within our bodies, so we're going to clear a few things up. Let’s start with the basics…

What is fiber and how much do we need?
Fiber is an indigestible carbohydrate found in plants.  While most carbohydrates are broken down into sugar molecules, fiber passes through the body intact. Dietary guidelines recommend a daily intake of 25 grams of dietary fiber for women and about 35 grams for men. But unfortunately, on average, Americans consume less than half of that.

Soluble vs. Insoluble Fiber
Fiber is typically classified by solubility. Soluble fiber attracts water and turns into a gel-like substance in your intestine, slowing digestion.  It keeps you feeling fuller longer and can help lower cholesterol and blood glucose levels. Good sources include beans, oats, apples, pears and lentils. 

Insoluble fiber does not dissolve in water and it works to "scrub"the intestines. It helps with feeling full and is good for maintaining healthy and regular bowl movements. Good sources include whole grains, flax seeds, cabbage, onions, lentils and all veggies really! 

Most plant-based foods contain a bit of both types of fiber.  However, the amount of each may vary depending on the source.  It is important to consume a variety of high-fiber foods to maximize the benefits of both types of fiber.

More Fiber, Less Problems
Moral of the story: you should aim to increase your fiber intake from a wide variety of different plant sources including fruits, vegetables, whole grains and legumes. Processed carbohydrates are essentially stripped of all of their natural fiber, which is just another reason to ditch the crap in favor of real, whole, fiber-full foods.

PSA: Make sure to increase the amount of H2O you are drinking when you begin increasing fiber intake! Fiber needs water to pass through your GI tract so drinking more water will keep things moving along and prevent some uncomfortable side effects.