Sep 5, 20236 min read

Fiber Health Benefits

Updated: Sep 10, 2023

From gut health to lowering cholesterol, increasing your fiber intake can benefit your health

Fiber is a carbohydrate that the body is unable to break down and digest. Instead, the body relies on the gut microbiome to accomplish this [1]. Fiber has many health benefits and is found in many plant foods, yet its importance seems to be overlooked and underemphasized by most people in the United States. There are two types of fiber -- soluble and insoluble. Despite the health benefits, around 95% of American children and adults do not meet the daily recommended allowance for fiber [2]!

Insoluble vs Soluble Fiber

Soluble fiber dissolves in water and forms a gel-like substance, which helps regulate blood sugar and lower cholesterol [3, 4]. Insoluble fiber doesn't dissolve in water and typically remains whole as it moves through your stomach. It increases the bulk of your stool and promotes movement in your digestive system [3, 4, 5]. Many fibrous foods contain both soluble and insoluble fibers [3].

Health Benefits of Fiber:

Decreased risk of diverticulitis [6, 7]
Lower cholesterol: More specifically, it lowers low-density lipoproteins (LDL's or "bad" cholesterol" [4, 5, 8, 9, 10, 11, 12].
Reduced risk of heart disease: Dietary fiber contributes to heart health in many ways, aside from reducing the risk of heart disease. For example, helping to lower triglyceride and cholesterol levels, blood pressure and inflammation [4, 5, 10, 13].
Reduced risk of heart attack [14]
Reduced risk of type 2 diabetes [13]
Reduced risk of breast cancer: High dietary fiber intake reduces the risk of developing breast cancer, in adolescence and early adulthood [15, 16, 17].
Control blood sugar levels: Fiber, specifically soluble fiber, helps slow the absorption of sugar into the body, controlling blood sugar spikes [5]. Additionally, foods high in soluble fibers cause smaller spikes in blood sugar [18].
Improved gut health: Humans cannot digest fiber, so it reaches the large intestine mostly in its original form. Once the bacteria reach the large intestine, their enzymes then digest these fibers [3]. The fiber feeds the good bacteria in the intestine, acting as prebiotics [19]. The bacteria also produce nutrients for the body. One of these nutrients is short-chain fatty acids (SCFAs) [20]. SCFAs can lower systemic inflammation, regulate your immune response, reduce gut inflammation and improved digestive disorders [21, 22].
Maintain a healthy weight: High fiber foods are often more filling and keep people full for longer, which can aid in weight loss or maintenance.
Bowel Health/Decreased Constipation: Fiber softens the stool while also increasing the bulk of the stool, decreasing constipation. A high fiber diet also lowers your risk of developing hemorrhoids [5].
- The catch: "In general, fiber that increases the water content of your stool has a laxative effect, while fiber that adds to the dry mass of stool without increasing its water content may have a constipating effect. [3]". It is important to drink enough water when increasing fiber intake so as not to cause constipation [23]. Additionally, one should try to consume a balance of soluble and insoluble fiber.

Daily Recommended Intake [24]:

	Women	Men
19-50	25g	38g
51+	21g	30g

Foods high in fiber:

Split Peas: 16.g per cup cooked/boiled split peas

Oats: 16.5g per cup raw oats, 4g cooked oats

Lentils: 15.6g per cup cooked/boiled lentils

Black Beans: 15g per cup cooked/boiled black beans

Avocados: 13.5g in one medium-sized avocado

Chickpeas: 12.5g per cup cooked/boiled chickpeas

Kidney Beans: 11g per cup cooked/boiled kidney beans

Chia seeds: 10g in 3 tablespoons chia seeds

Guava: 9g per cup

Collard Greens: 8g per cup cooked collard greens

Raspberries: 8g per cup

Blackberries: 8g per cup

Edamame: 8g per cup cooked edamame

Spelt: 7.5g per cup cooked spelt

Pears: 6g in one medium-sized pear

Quinoa: 5g per cup cooked quinoa

Artichoke: 4.5g in one cooked artichoke

Apples: 4.4g in one medium-sized apple

Brussels Sprouts: 4g per cup cooked Brussels Sprouts

Almonds: 4g per 1/4 cup

Sweet Potatoes: 3.8g in one medium-sized cooked sweet potato

Dark Chocolate: 3g in a one-ounce piece 70-85% cacao

Potatoes: 3.8g in one cooked potato

Sweet Potatoes: 3.7g in cooked sweet potato

Carrots: 3.5g per cup raw carrots

Beets: 3.4g per cup cooked beets

Beets: 3.4g in one cup cooked beets

Bananas: 3.1g in one medium-sized banana

Strawberries: 3g per cup

Flaxseeds: 3g in 2 tablespoons

Broccoli: 2.4g per cup cooked broccoli

Cauliflower: 2.3g per cup cooked Cauliflower

Tips to get more fiber:

Start your day with a high fiber breakfast like chia pudding or avocado toast. Explore some chia pudding recipes here.
Snack on guac, fruit or chia pudding.
Make a bean chili.
Leave the peel or skin on fruits and vegetables.
Read labels to help you understand how much fiber is in certain foods.
Switch from refined grains to whole grains.
Eat more whole fruits and vegetables, not juices. In the process of making fruit and vegetable juices, most of the fiber is stripped away.

When increasing fiber intake, your gut bacteria begins to change within a few days [25]. As you begin to eat more fiber, it is important to remember to drink plenty of water so as not to get constipated [23]. As someone who has struggled with digestive issues for years, I notice almost immediately when I don't eat enough fiber. I recommend that everyone, at least once, track how much fiber they eat in a day. I personally found the results shocking, as I wasn't consuming enough fiber. Now, I am just more conscious of making an effort to eat plenty of fiber.

Harvard t.h. chan school of public health. (2022, April). Fiber. https://www.hsph.harvard.edu/nutritionsource/carbohydrates/fiber/#:~:text=Fiber%20helps%20regulate%20the%20body%27s,vegetables%2C%20legumes%2C%20and%20nuts

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College of Agriculture, Consumer and Environmental Sciences. Kelly S. Swanson. University of illinois urbana-champaign. https://nutrsci.illinois.edu/directory/ksswanso