Updated: Jul 19
By: Betsy Stenard, Winthrop University Student
Fiber is a nutrient commonly discussed, and known to have an important role in the body. But what is it, and why is it necessary in our diet?
Dietary fiber is a major contributor to what helps keep us “regular” and avoid discomfort like constipation, bloating, and more. It is a type of carbohydrate with two forms: soluble and insoluble.
Insoluble Fiber cannot be broken down by our digestive system thus adds bulk to our stool and keeps us full for longer. It is often what people are actually referring to when a food “sticks to your ribs.” It is made up of plant cellulose, so whole fruits and vegetables, with the skins when applicable, are popular sources of insoluble fiber.
Soluble Fiber is broken down in water. It dissolves into a gel-like consistency that helps move food smoothly through our system and helps to avoid discomfort. Whole grains, like oats, are great sources of soluble fiber and also help to keep us fuller for longer.
The less processed the food source is, often the more fiber it will contain. For example, steel cut oats have more than twice the fiber than quick oats (5g per¼ cup vs 1g per ¼ cup) because they are less processed. Because of this, they also take longer to cook and more prep may be needed. With this said, quick oats still have their place! Often a large amount of fiber in one meal can lead to digestive discomfort, especially if our systems are not used to receiving very much very often.
Fiber can be a major contributor to helping to reduce inflammation, high cholesterol, IBS and IBD symptoms, and maintain a healthy gut. It can also help you maintain a healthy weight by helping you control your level of fullness. A healthy fiber intake also positively contributes to reduced gastrointestinal cancer and diverticulitis risk.
Some popular, high fiber foods to regularly include in your diet are:
Grains like oats, quinoa, popcorn,
Beans, legumes, lentils, peas, etc.
Fruits like apples and pears that contain high amounts of pectin (soluble fiber)
Vegetables like carrots, beets, and sweet potatoes
Cruciferous vegetables like cauliflower, broccoli, brussels sprouts, etc.
Nuts and seeds, especially almonds
So, how much fiber do we really need? It depends on the person on their own digestive tract, however the general guidelines are:
Adult women under 50: 25g/day
Adult men under 50: 38g/day
Adult women over 50: 21g/day
Adults men over 50: 30g/day
As always, natural sources of fiber are preferred over supplemental ones. Consuming enough fiber through the food we eat rather than supplemental sources is often better for our digestion and overall gut health. If you’re not sure if you’re getting enough fiber, it's always good to check with your registered dietitian or your general practitioner.
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