Protein’s PR team has been working overtime lately, and it’s paying off. It feels like everyone has a protein goal, cottage cheese is getting added to even the most random of recipes, and shelves are lined with brand new products engineered to have more of the macro (courtesy of the Kardashians). But, where protein is the hero and carbs are unfairly demonized, there’s another nutrient that people are sleeping on altogether: fiber.
“In America, unless you’re food-compromised, you are probably getting enough protein,” says Vanessa Rissetto, RD, the co-founder and CEO of Culina Health. “You need to get more fiber.”
Fiber, admittedly, isn’t the sexiest macro—it’s best known for helping you go to the bathroom—but it is super important. Over 90 percent of women aren’t meeting their daily fiber goals, according to the Dietary Guidelines for Americans. That’s 25 to 30 grams per day, to be exact.
But, they can. And they should. Eating fiber has a bunch of benefits, ranging from, yes, helping you go to the bathroom to lowering your risk of cancer. Here are all the reasons you might want to get more fiber (and how to do it).
Meet the experts: Vanessa Rissetto, RD, is the co-founder and CEO of Culina Health. Dana White, RD, is a sports nutritionist and trainer.
Fiber helps keep you regular.
This is probably one thing you do know about fiber: that it helps you go to the bathroom. There are two types—soluble and insoluble. Soluble fiber dissolves in water, forming almost a gel and softening your stool, says Rissetto. Think: chia seeds, oats, broccoli, and berries. If you’re having trouble getting things moving, try increasing your soluble fiber intake. (Psyllium, a common soluble fiber supplement, was found to increase bowel movements by three times per week compared to laxatives, which increased them by 2.5 times in a 2022 review in the American Journal of Clinical Nutrition.)
Meanwhile, insoluble fiber adds bulk to your stool. Examples of insoluble fiber are whole wheat flour, beans, nuts, and potatoes. If you’re having trouble going to the bathroom regularly, a balance of soluble and insoluble fiber should help.
Related StoriesIt might lower your cholesterol.
You know how Cheerios claim to help with cholesterol? That’s because they’re a source of soluble fiber, says Dana White, RD, a sports nutritionist and trainer. Fiber is non-digestable, meaning it travels throughout your GI tract without getting broken down—and that’s where a lot of its benefits come from. Soluble fiber sticks around and ferments in the gut, which alters the microbiome and contributes to lowering your cholesterol. It also absorbs cholesterol and helps it exit the body, says Rissetto.
In a randomized controlled trial, the group that added 3 grams of fiber to their diet saw an 11 percent decrease in blood cholesterol compared to the control, who saw a decrease of 4.1 percent, according to a 2019 study in Nutrients.
It keeps you full.
Like protein, fiber can help keep you full. There are a few reasons for this. First, it slows the absorption of nutrients, according to a 2018 review in Nature. Second, it has an effect on gastric emptying, blood sugar spikes, and the secretion of an often-talked about hormone called glucagon-like peptide-1 (GLP-1), per a 2022 review in Critical Reviews in Food Science and Nutrition. (GLP-1 is the hormone that weight loss drugs like Ozempic mimic that help signal to your body that you’re full.)
For this reason, it’s sometimes used to help with weight management, says Rissetto. And, while it can help keep you full, fibermaxxing—the trend where people are trying to overload on fiber to help with weight loss—is not necessarily the way to go, she says. Contrary to what the internet says, fiber is not the “poor man’s Ozempic.”
Related StoriesIt supports gut health.
Eating diverse sources of fiber helps fuel a healthier gut microbiome. Your microbiome proliferates every 60 days, and a lot of factors—from stress to your environment to your diet—can affect it. Fiber is one of those factors. “The more fiber you have, the healthier your GI tract will be,” says Rissetto.
Fiber is a prebiotic, meaning it serves as food so that the probiotics (the good bacteria in your gut) can do their thing. “When you’re eating enough fiber, you are healthier, your immunity is higher when it’s coupled with vitamin D, and so your body can do better work,” Rissetto says. But, fiber isn’t the end-all-be-all of a healthy gut. You’re going to want to make sure you eat probiotic foods like yogurt and kimchi too.
It reduces your cancer risk.
Another good reason to take your fiber intake seriously is that it is associated with a lower risk of many types of cancer, including esophageal, gastric, colon, rectal, breast, endometrial, ovarian, and pancreatic, according to a 2023 review in Nutrients.
As for why, exactly, there’s still more research to be done. But, at its simplest, since fiber helps increase the bulk of your stool and decrease transit time, it can dilute the amount of carcinogens in your colon and reduce your exposure to them, the review explains.
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It also might indicate other healthy habits that reduce cancer risk. “It’s about the behavior,” says Rissetto. “People who are eating adequate amounts of fiber are eating vegetables and fruits, they’re getting the benefits of the vitamins, the minerals, the antioxidants, and the diversification of the gut microbiome.”
But, make sure you eat it right.
If you’re one of the many people who don’t eat enough fiber right now, don’t go from zero to 30 grams right off the bat. You’re going to want to gradually increase your fiber intake, basically just to prevent any gastrointestinal side effects.
Then, it’s about identifying the fiber-full foods you already eat and seeing if you can either increase the number of servings you have throughout the week up the portion size when you do have them, says White. (Of course, you can always add new foods to your diet too.)
Pro tip: If you’re increasing your fiber intake, you also need to increase your water intake, says Rissetto. Shoot for 90 ounces of water per day, she says.
You’re also going to want to make sure you have multiple sources of fiber. “You really need to have a plentiful amount of fiber-rich foods spread out throughout the entire day,” says White. “It’s very rare that you’re going to have one meal with 25 grams of fiber, so it’s really more about a consistent intake.” One time you probably don’t want to eat fiber, though? Right before a workout. Since it’s non-digestable, it might not sit well in your stomach before physical activity.
Overall, if you’re part of the majority of people who don’t get enough fiber, consider this your sign to eat more—but don’t stress. “What I don’t want to see as a nutrition professional is what we’ve been seeing with protein, which is that people are overdoing it,” says White. “The message is that most people don’t get enough fiber and we should probably get more.”
Olivia Luppino is an editorial assistant at Women’s Health. She spends most of her time interviewing expert sources about the latest fitness trends, nutrition tips, and practical advice for living a healthier life. Olivia previously wrote for New York Magazine’s The Cut, PS (formerly POPSUGAR), and Salon, where she also did on-camera interviews with celebrity guests. She’s currently training for the New York City marathon.