Kristen Carli, Registered Dietitian Nutritionist | Camelback Nutrition & Wellness
I’m obsessed with fiber — my patients have heard my many rants on the subject. But my enthusiasm is for a good reason. Fiber is one of the most impactful, but most forgotten, nutrients that contributes to a healthy body, keeping your gut regular and your heart healthy.
Dietary fiber has been found to be influential in the maintenance and prevention of many health conditions and chronic diseases, including diverticulosis, colon cancer, obesity, diabetes, and atherosclerosis. The Dietary Guidelines for Americans recommends around 25-38 grams of fiber per day, but most Americans fall short of this averaging an intake closer to 16 grams per day.
What is Fiber?
Fiber is a catch-all term describing technically indigestible complex carbohydrates. Since they don’t break down and become absorbed into the bloodstream (like most other carbs do) these compounds add fecal bulk as they pass through your GI tract. This property makes them particularly beneficial for gastrointestinal disorders and constipation.
There are many types of fiber, but those with the most significant health benefits for people wanting to regulate their blood sugar or lower their cholesterol are soluble fiber. Soluble fibers are gel-forming and turn viscous when mixed with fluid inside the GI tract. If you’ve ever seen a chia seed transform to a gel-like substance, the effect is similar. Soluble fiber can increase fecal bulk and aid in excretion. Soluble fibers are found in foods such as legumes, whole grains, fruits, vegetables, and seeds.
How Fiber Balances Blood Sugar
After you eat food, your blood sugar will naturally rise, and with that, your pancreas secretes insulin to help transfer blood sugar to the cells of the body, where they can be used for energy. In those with type 2 diabetes, this process of transferring the glucose from your blood to your cells is impaired. Insulin is present in these individuals, but it is not very effective, a problem called insulin resistance. This is unlike in type 1 diabetes, where individuals are unable to make enough insulin, requiring insulin injections.
In individuals with type 2 diabetes, too many carbohydrate-rich foods could be very detrimental to their health because they can cause a large blood sugar spike that is unable to be lowered effectively by insulin. But not all carbs are alike. Simple carbs, or sugars, found in candy bars, sodas, juices, and even products made with white flour, are absorbed from the gut to the bloodstream very quickly. This contributes to a large spike in blood sugar. This spells trouble for people with diabetes. However, by increasing consumption of hard-to-digest carbohydrates, like dietary fiber, this effect is blunted. Because these sugars take time to breakdown in the gut, blood sugar isn’t spiked. Instead, it rises slowly and gradually, giving the body time to handle the modest increase in blood sugar.
How Fiber Lowers Blood Cholesterol
Soluble fiber, in particular, has the remarkable ability to decrease blood cholesterol. Considering fiber isn’t absorbed into our blood, where cholesterol causes damage to our vessels, how could this be? The answer is quite simple.. Because soluble fiber is gel-forming, your body is unable to reabsorb cholesterol-rich bile, which is secreted by the gallbladder anytime we eat. Typically, unused bile is reabsorbed to the body. However, with a high-fiber diet, this excess bile (and therefore cholesterol) becomes trapped in the undigested material. Thus, your body is left searching for ways to make more bile. So, it pulls out the cholesterol from your blood, turns it into bile, and thus your blood cholesterol is lowered. Pretty neat, huh?
Long story short, you likely need to eat more fiber! So how do you get started? While some foods have a higher fiber content than others, as a general rule of thumb, fiber is found in fruits, vegetables, nuts, seeds, legumes and whole grains. Use the tips below to jump-start your fiber consumption.
Ways to Increase Your Fiber Intake
- Add ground flaxseed to your baked goods.
- Sprinkle walnuts, almonds, sunflower seeds, chia seeds, or pistachios to your salads.
- Increase your intake of plant-based protein such as lentils, kidney beans or chickpeas.
- Aim to increase your intake of fruits and vegetables, such as pears, apples, dried apricots, dried figs, prunes, berries, turnips, Brussels sprouts, cabbage, broccoli, and carrots.
- Seek out sources of whole grains such as oats, quinoa or barley.
Remember fiber is not to be forgotten! I’d argue that it’s the most valuable nutrient we can consume. Add fiber-rich foods as often as possible, seeking out at least ½ of your plate as fruits and vegetables at each meal, and prepare to reap the health benefits!
About Kristen Carli, Registered Dietitian Nutritionist
Kristen is the owner of Camelback Nutrition & Wellness, a private nutrition practice in Scottsdale, Arizona specializing in chronic disease prevention and management as well as vegan/ vegetarian nutrition. She is a health & wellness contributor for Momsley, an outlet devoted to serving the modern mom. Having a passion for nutrition communication, she has been featured in InStyle, Bustle, Livestrong, The List, MyFitnessPal and many others. Kristen was selected to act as a Produce for Better Health Foundation Fruit and Vegetable Ambassador in Action, helping to promote the health benefits and importance of consuming fruits and vegetables. She also runs Mostly Green, a blog where she develops and shares simple plant-based recipes.