It’s estimated that 95 percent of us are deficient in one key nutrient, and it’s not protein. Or calcium. Or Vitamin D.
It’s fiber.
“It’s a real crisis,” Federica Amati, PhD, the head nutritionist at health-research institute ZOE, tells us. But why are things so urgent? Isn’t fiber’s primary function to keep us regular — and to keep things moving down there?
It turns out that’s only part of fiber’s job. In fact, the nutrient’s importance to our overall health can’t be understated, Dr. Amati tells us: Not eating enough of the stuff is associated with a higher risk of type 2 diabetes, heart disease, as well as certain cancers and chronic diseases.
“Its effects touch every part of the body,” says Dr. Amati, a self-proclaimed fiber fanatic.
What are the benefits of fiber?
Fiber is a carbohydrate that the body can’t break down, and there are two types: soluble and insoluble. Soluble fiber dissolves in water, forming a sludge-like substance in the gut. (If you’ve ever let a glass of Metamucil sit too long, you’ve got a sense of what it looks like.) While insoluble fiber passes through the intestines mostly intact, providing “roughage” and adding bulk to stools.
Fiber also famously plays an important role in regulating the digestive system. It slows the rate at which food moves through the gut and it makes you feel full, which can help with weight management. But scientists have also known for a long time that fiber has a profound impact on our cardiovascular health, too, because it helps the body excrete excess cholesterol, Dr. Amati says.
“If you’re eating enough fiber, that fiber surrounds the cholesterol in your intestines and keeps it from being reabsorbed,” she says. That’s why a high-fiber diet has the potential to lower cholesterol and can help prevent heart disease.
Beyond that, the nutrient supports the gut microbiome — the community of bacteria, fungi, and other microbes living in your digestive tract. There’s a growing (ahem) body of evidence that this ecosystem plays an important role in regulating our immune system, making sure our hormone levels remain in check, and much more.
Fiber provides fuel for the so-called “good” microbes in the microbiome — the ones that produce beneficial vitamins and other metabolites that decrease inflammation. That may be why eating enough fiber appears to have so many different benefits, from heart health to cancer prevention and even longevity. One large-scale analysis found that people who had the most fiber in their diets had a 15 percent to 30 percent reduced risk of death and chronic diseases, compared with those with the lowest intake.
How to incorporate more fiber into your diet
One easy way to get your fill is to start your day with a bowl of high-fiber cereal, like Fiber One or All-Bran, per Harvard Health. You can also try taking a supplement, like Metamucil or Benefiber, which contain a type of soluble fiber. As we mentioned earlier, these powdered products turn into a gel-like substance, which may help with managing food cravings and lowering cholesterol.
But to cultivate a healthy microbiome, you need to feed all the different types of microbes in your intestines with different types of fiber, Dr. Amati says. That means packing your diet with fiber-rich foods. Seeds are a great place to start, she tells us. Chia, flax, and pumpkin seeds are all very high in fiber, and you can sprinkle them into salads, soups, and even yogurt. Beans, nuts, and whole grains — like barley, quinoa, farro, and whole oats — are another excellent source.
How much fiber should you eat?
Currently, the average American eats about 14 grams of fiber a day. But it’s recommended that we consume up to twice that: Men 50 and under should be getting 38 grams daily, while women need 25 grams, according to the National Institutes of Health. (Doctors recommended that older men have 30 grams and older women have 21 grams per day.)
If we’ve convinced you to up your fiber game, Dr. Amati suggests changing your diet gradually — if you dive in with an extra-large lentil soup and bran muffin, you’re going to experience some bloating, she warns. But over time, consuming the proper amount of fiber can have “a transformative effect on your health,” she says. “You’ll be doing yourself a massive favor in the long term.”
