Nutrition / Food

6 Signs That You’re Not Eating Enough Fiber

Look out for these tells—you may be fiber deficient.

Fiber might as well be known as the fourth major macronutrient. The carbohydrate off-shoot is responsible for keeping us full, keeping us regular, and even protecting us from some cancers. And yet, it’s easy to forget about.

Sometimes it’s clear when you’re diet’s lacking in fiber—think bloating, cramping, constipation, or diarrhea. Other times, it’s not so obvious.

We asked experts to break down signs that you’re not eating enough fiber.

Fiber 4-1-1

“Fiber is the zero calorie, indigestible portion of carbohydrates,” says Samantha Hass, registered dietitian at F-Factor, a private practice that puts an emphasis on high-fiber carbohydrates. “It is found in the tough cell walls of plants—fruits, vegetables, legumes, and grains. Fiber is not found in animal products,” she adds. According to the Academy of Nutrition and Dietetics, women should aim for 25 grams a day, while men should aim for 38 grams (with those over 50 targeting 21 grams and 30 grams, respectively). Sadly, most American adults consume less than half of that, likely because of our overall heavy intake of processed foods.

But, it’s not all bad news. “A high fiber diet promotes optimal digestive and gut health, bowel regularity, and may help reduce your risk for chronic conditions, such as obesity, heart disease, Type 2 diabetes, and even colon and breast cancer,” Hass details. To reap these benefits, you just have to hit those aforementioned targets.

Sounds simple enough, but it doesn’t stop there. There are actually two types of fiber—soluble and insoluble—that are needed in a well-rounded diet. “Soluble fiber swells in your stomach, provides bulk to foods, and keeps you feeling full. Insoluble fiber speeds up the passage of materials through the digestive tract,” says Hass.

Confused? No need to be. Eating enough total fiber is sure to provide you with enough of both types.

Along with a proper diet, your workouts are important to keep you healthy. Learn more about how Aaptiv can take your workouts to the next level.

Not sure if you’re getting enough total fiber? Keep scrolling to find signs that your diet is lacking.

You’re having trouble in the restroom.

The most obvious signs that you’re not eating enough fiber are stomach issues, most commonly, constipation, and diarrhea. When it comes to the former, Hass informs us that “Irregular bowel movements may be a sign [that] you aren’t getting enough fiber. [Fiber] helps normalize transit time by moving contents along the digestive tract. It also absorbs water, which leads to softer stools, making it easier to pass through your digestive tract.” In short, fiber helps keep things moving through and out of your body. If things are at a stand-still, chances are there’s not enough roughage helping it through.

On the other hand, you could experience diarrhea. While the two ailments may seem like total opposites, they’re both common results. The difference is that, while constipation is a result of food not moving out of your digestive tract, diarrhea happens when when undigested food moves through too quickly. Because fiber absorbs water, it aids in adding bulk to your stool and combats that too-soon release. “[Eating enough fiber] will slow down digestion and give time for your intestines to absorb additional water, leading to formed solid stools,” says Hass.

You’re hungry after meals.

Not only does fiber keep you regular, but it also keeps you satisfied. Eating enough fiber helps you feel fuller longer. This is why so many people turn to it to aid in losing and maintaining weight. Feeling hungry after meals could be a sign that you’re not including enough fiber in them.

High-fiber foods tend to take longer to chew, therefore slowing your eating. When this happens, you’re more in tune with when you feel full. “Fiber also takes longer to digest, which prevents any excessive snacking or cravings between meals,” Hass explains. “Therefore, when you follow a diet rich in fiber, you feel full after eating. You’ll generally eat less throughout the day, leading to sustainable weight loss and/or weight maintenance.”

Carrie Dennett, MPH, RDN, CD and creator of Nutrition by Carrie adds to this: “If you aren’t eating many fiber rich foods like whole grains, fruits, vegetables, beans, nuts and seeds, then you’re probably eating more processed foods, including carbohydrate-rich foods made from refined white flour.” These refined foods aren’t just unsatisfying, but can lead to further cravings. “These ‘fast carbs’ can lead to spikes and crashes in your blood sugar, leaving you tired, hungry, and craving more carbs,” Dennett explains.

Whether or not weight loss is your goal, including enough fiber in your meals will help keep you satisfied and happy with your snacks and meals.

Your cholesterol is high.

Yes, really. According to research, consuming enough fiber may help lower your risk of cardiovascular disease by improving cholesterol, lowering blood pressure, and reducing inflammation (we’ll touch on that in a bit). “Soluble fiber acts like a sponge and absorbs cholesterol in the small intestine and passes it through the digestive tract as waste,” explains Hass. Moreover, soluble fiber in the large intestine produces short chain fatty acids that help with preventing cholesterol synthesis (production) in the liver. If you suspect or know that you have high cholesterol, consider upping your fiber intake. And, of course, consult a professional.

You have inflammation.

If you’re experiencing inflammation, you might suspect that you’re not drinking enough water. One likely possibility, though, is that you’re not getting enough fiber. “A low-fiber diet means [that] you aren’t nourishing the “good” bacteria and other microbes in your large intestine, which can throw your gut microbiota out of whack. A healthy, diverse, balanced gut microbiota is important for good health, in part because it can help prevent chronic inflammation,” Dennett explains. “Most of our immune system cells live in our intestinal walls. So when our gut microbiota is unhealthy or unbalanced, there’s a better chance that our immune system will unnecessarily unleash inflammation on the body.”

To sum it up, not eating enough fiber could potentially lead to not feeding the good bacteria in your gut. When this happens your body may become inflamed. While this may not seem like a big deal, chronic inflammation is linked to heart disease, diabetes, and some types of cancer. So it’s ideal that we feed our good bacteria (by eating fiber, for example).

You’re low on energy and not sleeping well.

If you find it hard to get up and do your morning workout, you could be low on fiber. “Adding fiber to your meals keeps blood glucose levels stable, providing your body with sustainable energy throughout the day,” says Hass. Remember how eating refined carbs raises your blood sugar and makes you crave more carbs? Well, it can make your blood sugar levels crash repeatedly, disturbing your sleep cycle. Eating enough fiber can combat this, raising your energy levels and helping you sleep at night. Feeling an afternoon slump? Hass suggests snacking on high-fiber foods, like fruit or fiber crackers (specifically, mini cracker pizzas, because—despite popular opinion—fiber can be delicious).

You have stubborn acne.

Diet and acne are closely linked. Fiber, although not the most obvious contributor, can play a large factor in breaking out. “Fiber soaks up toxins in the blood and eliminates them through the digestive tract, instead of your pores,” Hass describes. Thus, eating enough fiber allows your body to release excess toxins and potentially clear up your skin. Pro tip: Fruits and vegetables that are rich in fiber are likely also full of antioxidants, which also promote bright, healthy skin.

It may sound counterproductive, but if you relate to any of these indicators, resist upping your fiber straight away! A sudden increase in fiber can throw off your gut, leading to indigestion and constipation. Instead, increase slowly and allow your body to take time to adjust. “Some species of gut microbes—the types that don’t really benefit us—thrive on low-fiber, high-fat diets. When you throw fiber at them, they can’t digest it, which can cause us digestive distress. Gradually, the good microbes who like fiber will start to take over, as they realize they will have enough food to support them,” says Dennett.

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