Are You Getting Enough Fiber?
Many of us recognize the importance of counting calories, and watching our intake of sugar, carbohydrates, protein and fats when we are monitoring our diets. But many of us overlook the importance of one key nutrient: Fiber. Also known as “roughage” or “bulk,” fiber refers to the parts of plant foods that our body cannot digest and absorb. According to experts, the recommended daily intake of fiber is 25 grams for women and 38 grams for men, yet the vast majority of Americans – 1 in 20 - fall short of those numbers, consuming an average of around 16 grams of fiber per day. Hitting those numbers, however, can contribute to weight loss and reduce the risk of disease by optimizing how the gut functions.
Benefits of Fiber
“Fiber is beneficial for many things,” says Kroger culinary dietitian Ashley Martinez, MFN, RDN, LD, NASM-CPT. “It is super valuable for supporting health of the microbiome in the gut, and there is a correlation with gut health and longevity, and also with immune health.” A high-fiber diet can also help to regulate bowel movements, maintain bowel health, regulate blood sugar, blood pressure and cholesterol levels, reduce the risk of cardiovascular disease and aid in weight loss. A recent study showed that just two weeks of a high-fiber diet can significantly alter the gut microbiome; dietary fiber resists digestion, but is metabolized by bacteria in our guts into byproducts that are critical for our health. Eating a variety of high-fiber foods, such as fruits, vegetables and whole grains, fuels the health of the gut microbiome, while eating low-fiber foods, only a few types of fiber, or even the same fiber supplement each day, can harm your gut microbiome.
What is Soluble Fiber?
Soluble fiber dissolves in water, which means it dissolves in the gastrointestinal fluids once it enters the stomach. It transforms into a gel-like substance that serves as food for bacteria in the intestines. Foods like oats, barley, beans and peas, and some fruits and vegetables, like brussels sprouts, avocado and citrus fruits, are high in soluble fiber. “Research suggests soluble fiber is linked to reducing overall blood cholesterol,” explains Martinez. “If you are eating enough soluble fiber, it binds to cholesterol in the blood and allows it to be excreted rather than allowing the cholesterol to stay in the blood.”
What is Insoluble Fiber?
Insoluble fiber does not dissolve in water and is therefore not broken down as it moves through the digestive track. It acts like a broom, sloughing out the intestines. Foods like whole wheat flour, wheat bran, nuts, beans, and vegetables like green beans, cauliflower, celery, cucumbers and potatoes are high in insoluble fiber. “Insoluble fiber is the bulk,” says Martinez. “It’s more stiff and can clean out the digestive tract.” Martinez also notes that many fruits and vegetables, like broccoli, apples and carrots, contain both insoluble and soluble fiber.
How Do You Know if You Are Getting Enough Fiber?
According to Martinez, if you are not getting at least two to four cups of fruits and vegetables each day, or if at least half of each meal does not consist of fruits and vegetables, you are likely not getting enough fiber. Additionally, if you are hungry very often, there is a good chance you need more fiber. “If you have frequent hunger pain, it’s likely you’re not getting enough satiety from foods high in fiber,” Martinez says. “You are probably eating things that are not digesting slowly. When you eat foods that digest quickly, like soda or candy, you can be hungrier more often.” Lastly, if you’re constipated, a lack of sufficient fiber could be the culprit, though Martinez points out that getting enough fluids and exercise can also contribute to constipation.
Can You Eat Too Much Fiber?
In a word, yes, but it’s very difficult to do, given the fact that most people do not consume enough. Slowly increasing your fiber intake can ward off some of the potential problems caused by eating too much fiber, such as digestive distress, gas, bloating, or, in extreme cases, intestinal blockages.
Fiber and Processed Foods
Refined foods, like white bread and pasta, are low in fiber. Even ultra-healthy green juices can be considered processed in this sense, because all the insoluble fiber is removed from the green vegetables before they are consumed. However, fiber can also be added to processed foods. Many dairy products, like yogurt, milk and ice cream, contain added fiber. Be sure to read nutrition labels to track your fiber intake, and eat lots of fruits, vegetables and grains as close to their natural form as possible.
Should You Take a Fiber Supplement?
“Supplements are exactly that: supplemental,” says Martinez. “I believe in looking to food first, but if you simply do not and cannot consume enough fiber per day to reach the recommended daily intake, a fiber supplement is the next best thing.” Martinez notes that many fiber supplements come with added sugar and flavor enhancers, and while supplements with fewer ingredients and less sugar are always better, if added flavoring or sweetener helps you to consume more fiber, it is in your best interest to have it in that form.