CHARLOTTE – Dietary fiber. You’ve read about it, wonder if you’re getting enough — maybe even taken a fiber supplement. But what, exactly, is fiber? How does it help us stay healthy?
“Sometimes called ‘roughage,’ dietary fiber is actually a kind of carbohydrate that doesn’t break down into sugar molecules the way other carbs do,” said Chandler Nunes, registered dietitian at Novant Health Bariatric Solutions, in Charlotte. “So, while your body absorbs proteins, fats and other carbs, fiber actually passes through your body without being completely digested.”
Found primarily in plant foods like produce, legumes and whole grains, dietary fiber offers many health benefits including:
- Maintaining steady blood sugar levels and improving insulin sensitivity.
- Reducing serum cholesterol levels.
- Lowering your risk for life-threatening conditions, including heart disease, obesity, stroke and Type 2 diabetes.
To reap these and other benefits, it’s necessary to cut through some of the myths and marketing hype surrounding fiber. So, we turned to Nunes to clear up five of the most common misconceptions. An added bonus: She also offered two delicious, fiber-rich recipes (below).
Myth No. 1: Fiber is fiber — it’s all the same.
Actually, there are two types of fiber: soluble and insoluble.
Soluble fiber mixes with water in the body and becomes gel-like. This gel slows digestion, which can keep you feeling full after eating. Soluble fiber is also helpful in controlling blood glucose and cholesterol levels. Foods higher in soluble fiber include:
- Oats, barley
- Peas, beans
- Apples, citrus fruits, carrots
- Psyllium (seed husks from the Plantago ovata plant)
Insoluble fiber, also called “roughage,” does not mix with water. When you consume it, this type of fiber can relieve constipation by adding bulk to your stool and helping it pass. Some examples of foods rich in insoluble fiber are:
- Whole-wheat flour, wheat bran
- Nuts, beans
- Cauliflower, green beans and the skins of fruits and veggies
All fiber rich foods contain both types, but the proportions of soluble vs. insoluble fiber vary.
Myth No. 2: Eating oatmeal for breakfast provides all the fiber you need.
A cup of oatmeal has a great nutrition profile, but at 4 grams of fiber it falls far short of recommended daily amounts. In fact, with an average fiber intake of only 16 grams per day, an estimated 95% of Americans fail to meet the U.S. Department of Agriculture’s fiber recommendations.
The amount of fiber we need depends on our age and gender, according to the USDA’s Dietary Guidelines for Americans:
- Women 20 to 50: 25-28 grams per day.
- Women 51 and over: 22 grams per day.
- Men 20 to 50: 31-34 grams per day.
- Men 51 and over: 28 grams per day.
- Children: Needs vary widely. Check with your health care provider.
Interestingly, the amount of fiber we need decreases as we age, because our digestion tends to slow down naturally over the years. So, to avoid gastrointestinal discomfort, people 51 and over should reduce their intake.
Also, a recent study revealed that some people with inflammatory bowel disease (IBD) may be unable to digest dietary fibers. If you have IBD or any other health concerns, always check with your health care provider before changing your diet.
Myth No. 3: If “enough” fiber is good, more must be better.
Even though fiber is beneficial, it is possible to consume too much. Eating more than the recommended daily amount of dietary fiber can cause bloating, constipation, abdominal discomfort and gas. Plus, if you get too much soluble fiber, it can bind to certain nutrients, like calcium and iron, as well as to some medications, interfering with your body’s ability to absorb them as needed.
If you do need to increase your fiber intake, do so gradually. And be sure to increase your fluid intake, too, so you don’t become constipated or have discomfort.
Myth No. 4: All I need for a healthy gut are probiotics.
Probiotics, the trillions of microbes and bacteria that live in our gut, can boost physical and mental health and strengthen your immune system. However, probiotic microorganisms need to be properly “fed” — much as you would give plant food to your garden — with certain types of fiber known as prebiotics to keep them strong and ensure you get their full benefits.
Some of the best prebiotic foods include:
- Apples (with the skin on), bananas and berries.
- Legumes (soybeans, peas, lentils).
- Barley, wheat bran and oats.
- Onions and garlic.
- Dark chocolate.
Researchers have found that people who eat fiber-rich whole foods obtain far more benefits from probiotics supplements than those who take supplements without increasing their fiber intake at all.
Myth No. 5: I should count “net carbs” because fiber is never digested.
Counting “net carbs” — subtracting the number of grams of fiber and sugar alcohols from the total carbohydrate count because they aren’t absorbed by the body and therefore don’t add calories — is popular right now.
But this equation is not backed up by science. And, in reality, our bodies actually may digest certain fibers and sugar alcohols. So it gets complicated.
A better approach to control your carb intake is to simply eat more nutritious, fiber-rich starches, like whole grains, legumes and vegetables. That way your “net carbs” will be lower, naturally.