Are you getting enough fiber? It's one of the most overlooked nutrients, doctor says—when to consider a supplement

There are so many nutrients that our bodies need, so it's easy to miss out on getting enough of each one. And fiber is one nutrient that is really important, but often overlooked.

Less than 10% of U.S. adults are getting the recommended daily intake of fiber, according to a study that was presented at Nutrition 2021 Live Online.

For adults aged 50 and under, the U.S. Department of Agriculture recommends that women get 25 grams of fiber a day, and men get 38 grams daily. For those over the age of 50, women should aim for 21 grams and men should aim for 30 grams a day, according to Harvard Health Publishing.

Typically, American adults are only eating about 10 to 15 grams of total fiber a day, Harvard Health Publishing states.

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This "may be, in part, because [people] don't realize the importance. Fiber is something that we can easily take in every day," according to Dr. Kellyann Petrucci, a celebrity nutrition expert and New York Times best-selling author.

Does that mean everyone should take fiber supplements? Or are there better, simpler ways to get the nutrient?

And why do we even need fiber to begin with?

Here's what Petrucci says.

Why is fiber so important for overall health?

We're learning more and more just how much gut health can affect other areas of our lives including brain health, immunity and skin health, Petrucci says.

"The gut has a favorite food, and that favorite food is fiber," she notes.

"What happens is, if you don't get enough fiber, then the bugs, or the microbes that are very important [and] that line your entire gastrointestinal system, they don't get what they need. So they don't have that good material to chomp on [and] they start chomping on the gut lining."

This process leads to what is commonly known as "leaky gut," Petrucci says. Leaky gut is essentially large cracks in your gut lining that can invite harmful things into your gut like toxins and partially digested food, which can cause inflammation, according to Harvard Health Publishing.

"So it's just something that we need to keep in check," Petrucci says. "Fiber happens to be an easy way that we can do that."

Having a diet that is high in fiber can also help to maintain hormone levels in women, she adds. Fiber has been found to reduce blood sugar and estrogen levels, which may be why it was linked to an 8% lower chance of developing breast cancer in women who ate fiber-rich diets in comparison to those who didn't.

How should you get your daily fiber intake?

Petrucci strongly recommends trying a food-first approach to get fiber on a daily basis. "I always prefer food because you're getting so many of the other nutrients along with the fiber," she says.

Some fiber-rich foods that you can reach for are:

• Avocados
• Leafy greens
• Cruciferous greens like broccoli, cauliflower, bok choy and Brussel sprouts
• Raw almonds
• Berries
• Apples
• Seeds like chia seeds, flax seeds and sunflower seeds

However, Petrucci understands that for certain reasons, like time, that it can be hard to track how much fiber you're getting through your diet.

"I try to meet people where they are," she says, while considering, "how can they make this work for them? So if you have to take a supplement, I would take a supplement."

When it comes to supplements, Petrucci encourages you to get a supplement that has these three things:

• A superfood
• Some kind of fish oil for Omega-3s
• Insoluble and soluble fiber

Petrucci says most people should aim for a fiber supplement that is around 10 grams of fiber. She also notes that some people may want to avoid taking a fiber supplement with psyllium because it has caused constipation and bloating for certain people.

"You want to make sure you get fiber-rich foods every day [and] drink liquids to get everything moving through your colon," Petrucci says.

"Start looking at the [food] label. You want some kind of fiber in there. Particularly, if you're getting sugars or more carbohydrate-laden foods, you don't want carbohydrates that don't have any fiber in them; it's not going to make you feel well in the end."

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