Dietary fiber, also known as roughage or bulk, includes the parts of plant foods your body can't digest or absorb. Unlike other food components, such as fats, proteins or carbohydrates — which your body breaks down and absorbs — fiber isn't digested by your body. Instead, it passes relatively intact through your stomach, small intestine and colon and out of your body.
Fiber provides several health benefits:
- It normalizes bowel movements by increasing the weight and size of your stool and softening it.
- It helps maintain bowel health by lowering your risk of developing hemorrhoids and small pouches in your colon (diverticular disease).
- It lowers cholesterol levels by lowering low-density lipoprotein, or "bad," cholesterol levels.
- It helps control blood sugar levels by slowing the absorption of sugar, which for people with diabetes can mean improved blood sugar levels.
- It aids in achieving a healthy weight by making you feel fuller faster.
There are two types of dietary fiber: soluble and insoluble.
- Soluble fiber: This type of fiber dissolves in water to form a gel-like material. It can help lower blood cholesterol and glucose levels. Soluble fiber is found in oats, peas, beans, apples, citrus fruits, carrots, barley and psyllium.
- Insoluble fiber: This type of fiber promotes the movement of material through your digestive system and increases stool bulk, so it can be of benefit to those who struggle with constipation or irregular stools. Whole-wheat flour, wheat bran, nuts, beans and vegetables, such as cauliflower, green beans and potatoes, are good sources of insoluble fiber.
The daily recommended intake of fiber for men is 38 grams and for women, it's 25 grams. For management of cholesterol, having 5-10g of soluble fiber can be helpful (aim for 1-3g per meal).
Please note: This is a general recommendation, and may not be appropriate for certain medical conditions or personal tolerance, so it is important to discuss with your care team to find the amount of fiber that is right for you.
Soluble Fiber Foods and Their Fiber Content
- Oats: 1 cup contains about 4 grams of soluble fiber
- Peas: 1 cup contains about 2.6 grams of soluble fiber
- Beans: 1 cup contains about 4-7 grams of soluble fiber (depending on the type of bean)
- Apples: 1 medium apple contains about 1.2 grams of soluble fiber
- Citrus fruits: 1 orange contains about 1.8 grams of soluble fiber
- Carrots: 1 cup of chopped carrots contains about 2.3 grams of soluble fiber
- Barley: 1 cup contains about 2 grams of soluble fiber
- Psyllium: 1 tablespoon contains about 5 grams of soluble fiber
Insoluble Fiber Foods and Their Fiber Content
- Whole-wheat flour: 1 cup contains about 14.6 grams of insoluble fiber
- Wheat bran: 1 cup contains about 24.8 grams of insoluble fiber
- Nuts: 1 ounce of almonds contains about 3.5 grams of insoluble fiber
- Beans: 1 cup contains about 6.2-9.6 grams of insoluble fiber (depending on the type of bean)
- Vegetables: 1 cup of cauliflower contains about 2 grams of insoluble fiber, 1 cup of green beans contains about 2.7 grams of insoluble fiber, and 1 cup of potatoes contains about 2.2 grams of insoluble fiber
You can add more fiber to your diet by incorporating more fiber-rich foods into your meals and snacks. This can include eating more fruits, vegetables, beans, lentils, whole grains, and nuts.
Start slow and work up gradually! Sometimes, going from a lower fiber to a higher fiber diet can cause stomach discomfort/upset, so adding in a little bit at a time gradually can help with tolerance.
Here are some specific tips:
- Start your day with a high-fiber breakfast. Consider options like oatmeal, whole grain bread or cereal, or a smoothie with fruits and vegetables.
- Add more vegetables to your meals. This can include adding spinach to your morning omelette, having a salad with lunch, or filling half your plate with vegetables at dinner.
- Snack on fruits and nuts. These can be a great source of fiber, and they're easy to take with you on the go.
- Choose whole grains. This can include choosing whole grain bread for your sandwich, or brown rice instead of white rice.
- Include legumes in your diet. Beans, lentils, and peas are high in fiber and can be added to many meals. Remember to increase your fiber intake gradually to avoid digestive discomfort, and to drink plenty of water as you increase your fiber intake.