Fiber Bars: Nutrition, Benefits, Healthiest Bars

Many people report a love-or-hate relationship with fiber bars — though this may be more about their effects on digestion than on the taste buds.

Fiber bars can be an easy and convenient way to boost your fiber intake, which may help regulate your digestion and promote better overall health.

However, not all fiber bars are created equal.

This article explores what fiber bars are, their benefits and downsides, and how to select a healthy brand of fiber bars.

Fiber bars are one of the easiest ways to boost your fiber intake. They’re portable, fiber-packed, and shelf-stable.

Fiber bars often feature fiber-rich ingredients such as nuts, oats, seeds, and fruits.

Many of these bars also contain more processed fiber powders like psyllium husk powder and chicory root fiber.

They may also feature other ingredients — such as protein, vitamins and minerals, herbs, or probiotics — that offer potential health benefits.

Adding fiber bars to your routine

If you’re not used to eating fiber bars or eating large amounts of fiber, you’ll want to start slowly to avoid any unpleasant digestive side effects when adding fiber to your routine.

Some people report experiencing side effects like stomach pain, bloating, diarrhea, or constipation after trying a fiber bar for the first time (1).

To start, try eating one fiber bar (or just half of one) in a given day and be sure to drink plenty of water, which may help alleviate some of the digestive issues associated with increased fiber intake (2).

Drinking enough water also promotes bowel regularity, so it’s a good idea whether you’re eating fiber bars or not.

Over time, your body will adjust to this new level of fiber consumption.

Still, it’s best to get your fiber from real, whole foods when possible. Save the fiber bars for times when you’re unable to access these fresh and fibrous foods.


Fiber bars are a convenient, portable way to boost your fiber intake.

Fiber bars offer many potential health benefits, especially if you find it difficult to get enough fiber every day from food sources such as fruits, vegetables, whole grains, nuts, seeds, and legumes.


Fiber bars are a convenient way to increase your fiber intake. Many people reach for them as a quick breakfast on busy mornings or a snack at work or school. You can also turn to them as fuel for hikes, workouts, or camping trips.

Most fiber bars are shelf-stable and individually wrapped, so you can store them in your purse, backpack, car, or desk drawer. This makes them an ideal option when fiber-rich whole foods aren’t available.

Digestive health

Fiber offers several potential benefits for digestive health.

Soluble fiber, which is found in foods such as oats, beans, chia seeds, and apples, forms a gel in the presence of liquid. This gelling action can help soften your stool and make it easier to have a bowel movement if you’re experiencing constipation (3).

Common in foods like nuts, beans, and wheat bran, insoluble fiber adds bulk to stool, which may also help relieve constipation (4).

Fiber also helps promote digestive regularity by preventing digestion from occurring too rapidly.

Additionally, fiber is considered a prebiotic — a food source for the healthy bacteria that live in your large intestine (5).


Fiber fills you up. It slows down digestion, keeping food in your digestive tract longer, which makes you feel full (6).

Another filling component of food is protein, and these two nutrients are often combined in bars. Many fiber bars contain protein, and many protein bars contain fiber (6).

Other benefits of fiber

Fiber also provides some other potential benefits:

  • Weight management. Fiber may have a small effect on weight management and body fat, independent of calorie consumption (7).
  • Cholesterol reduction. Soluble fiber may bind to dietary cholesterol and prevent your body from absorbing it. This may help reduce your blood cholesterol level (4).
  • Blood sugar management. Fiber may help keep your blood sugar from rising quickly in response to eating high carbohydrate or sugary foods. This can help you manage appetite- and blood-sugar-regulating hormones such as insulin (4).


Fiber bars are convenient. Their fiber content may promote digestive health, satiety, weight control, cholesterol management, and blood sugar management.

On the other hand, fiber bars have their downsides.

Some people experience digestive issues after eating fiber bars.

In addition, many of these bars are processed, containing additives such as sugar, preservatives, or flavorings. Research shows that processed foods have been associated with weight gain, obesity, and chronic disease (8).

Some fiber bars are also high in added sugar. Excessive added sugar intake is associated with obesity, type 2 diabetes, heart disease, fatty liver disease, and other chronic conditions (9).

Additionally, some fiber bars contain fibers that you wouldn’t typically consume in large quantities. Even if they’re natural ingredients, fiber additives like psyllium husk and chicory root fiber may cause digestive discomfort in some people (10, 11).

These bars are not whole foods, so it’s important to consume them in moderation and strive to get most of your fiber from whole food ingredients such as fruits, nuts, seeds, whole grains, legumes, and vegetables.


Some fiber bars are highly processed and contain added sugars. Additionally, certain fibers used in these bars may contribute to digestive discomfort in some people.

I spoke with some fellow dietitians about some of best fiber bars and included one or two that I really like as well. If you’re interested in buying fiber bars, here’s what to look for when you shop:

  • At least 5 grams each of fiber and protein. Adults need at least 25 grams of fiber per day, so a bar with 5 grams provides a significant chunk of that. Additionally, protein helps promote fullness (12).
    • “The more fiber and protein,” explains Dana Gardner, MS, RD, LDN, owner of Jax Fresh Mobile Market, “the fuller you may feel, which may curb appetite.”
  • Minimal added sugars and sugar alcohols. Added sugars may contribute to chronic diseases such as type 2 diabetes and heart disease, while large amounts of zero-calorie sugar alcohols can contribute to digestive upset.
    • Try to choose bars sweetened with natural ingredients such as fruit rather than bars that contain large amounts of added sugar or sugar alcohols (9, 13).
  • Whole food ingredients. Look for fiber bars that are made simply, with whole food ingredients such as nuts, seeds, oats, and fruit.
    • “Whole foods sources of fiber contain much more than just fiber,” says Silvia Carli, MS, RD, of 1AND1 LIFE. “They contain vitamins, minerals, and antioxidants.”

Here are some great fiber bar options to check out.

Dietitian recommended: KIND Bar

Among the dietitians I spoke with, KIND was the most highly recommended fiber bar because of its low sugar content and included protein. In particular, the Dark Chocolate Nuts & Sea Salt flavor came highly recommended.

“It has a rich taste that satisfies a sweet tooth,” explains Cheryl Mussatto, MS, RD, LD, clinical dietitian at Cotton O’Neil Endocrinology and Diabetes Clinic in Topeka, Kansas, “but you know you’re eating a healthy combo of nutrient rich ingredients.”

One KIND Dark Chocolate Nuts & Sea Salt bar provides (14):

  • Calories: 180
  • Fat: 15 grams
  • Protein: 6 grams
  • Carbs: 16 grams
  • Fiber: 7 grams
  • Total sugar: 5 grams
  • Added sugar: 4 grams
  • Sugar alcohol: 0 grams

Keto-friendly: CORE Keto Bar

CORE Bars are a popular plant-based option, and their new keto line is tasty and packed with prebiotic fiber and even contains probiotics.

These bars are sweetened with allulose, a sweet compound found in small amounts in dried fruits. It’s a unique type of sugar that provides few calories and has a minimal effect on blood sugar levels (15).

One CORE Peanut Butter Chocolate Keto Bar contains (16):

  • Calories: 170
  • Fat: 12 grams
  • Protein: 7 grams
  • Carbs: 17 grams
  • Fiber: 7 grams
  • Total sugar: 2 grams
  • Added sugar: 0 grams
  • Sugar alcohol: 0 grams

Highest in protein and fiber: Atlas Bar

Taylor Fazio, MS, RDN, CDN, wellness advisor at The Lanby, says, “Atlas Bars are one of the best bars on the market, with 10 grams of fiber, no added sugar, and 15 grams of protein.”

These bars do contain some sugar alcohol in the form of vegetable glycerin (also known as glycerol). To help prevent digestive issues, it’s best not to eat more than one serving at a time.

A Peanut Butter & Raspberry Atlas Bar provides (17):

  • Calories: 220
  • Fat: 10 grams
  • Protein: 16 grams
  • Carbs: 21 grams
  • Fiber: 10 grams
  • Total sugar: 1 gram
  • Added sugar: 0 grams
  • Sugar alcohol: 7 grams

For kids: Cerebelly Smart Bar

It can be challenging for kids to get enough fiber, especially if they’re picky about fruits and vegetables. Fortunately, young children need only 17–20 grams per day, so even a tiny bit of fiber in a bar can make a big difference (12).

These bars from Cerebelly are recommended by Angela Houlie, MS, RDN, CDN, founder of My Fruitful Body Nutrition, because “they are a good source of fiber, contain no added sugar, and contain many additional vitamins and minerals.”

One Cerebelly Carrot Raisin Smart Bar provides (18):

  • Calories: 90
  • Fat: 3 grams
  • Protein: 3 grams
  • Carbs: 15 grams
  • Fiber: 3 grams
  • Total sugar: 6 grams
  • Added sugar: 0 grams
  • Sugar alcohol: 0 grams

Great-tasting: IQBar

Another great choice for a fiber bar that also provides protein is the IQBar. These bars feature nuts as their first ingredient and contain other healthy whole food ingredients like flaxseed and lion’s mane mushroom. They’re also free of sugar alcohols. In my opinion, the Almond Butter Chip and Peanut Butter Chip bars taste like dessert too.

The Almond Butter Chip IQ Bar contains (19):

  • Calories: 180
  • Fat: 12 grams
  • Protein: 12 grams
  • Carbs: 13 grams
  • Fiber: 10 grams
  • Total sugar: 1 gram
  • Added sugar: 0 grams
  • Sugar alcohol: 0 grams

Made with whole foods: RX Bar

Another bar that’s highly recommended among dietitians is RX Bar. RX Bars are made with only whole ingredients — no processed fibers, sweeteners, or other ingredients are added.

For instance, the only ingredients in the Mixed Berry RX Bar are dates, egg whites, almonds, cashews, cranberries, strawberries, raspberries, and natural flavors. This bar also contains (20):

  • Calories: 210
  • Fat: 7 grams
  • Protein: 12 grams
  • Carbs: 24 grams
  • Fiber: 5 grams
  • Total sugar: 15 grams
  • Added sugar: 0 grams
  • Sugar alcohol: 0 grams

Most affordable: Fiber One Protein Bar

Fiber One Bars may be the most popular fiber bar of all. They’re one of the most affordable and available options too.

However, Fazio says, “Relying on Fiber One bars is not the most ideal way to get overall dietary fiber.” This is because they’re highly processed and contain sugar alcohols that may affect your digestion.

The Peanut Butter Fiber One Protein Bar contains (21):

  • Calories: 130
  • Fat: 7 grams
  • Protein: 6 grams
  • Carbs: 15 grams
  • Fiber: 7 grams
  • Total sugar: 2 grams
  • Added sugar: 2 grams
  • Sugar alcohol: 3 grams


Look for fiber bars with at least 5 grams of fiber, 5 grams of protein, minimal added sugar and sugar alcohols, and whole food ingredients.

Fiber bars can be a great solution if you have trouble getting enough fiber or if you need a filling on-the-go snack. However, some fiber bars are highly processed and may contain potentially harmful ingredients such as added sugars or sugar alcohols.

The best fiber bars you can buy contain both fiber and protein, are made from whole food ingredients, and have little or no added sugar or sugar alcohols.