Can Fiber Bars Cause Constipation?

Two fiber bars and a bowl of blueberries.
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Fiber bars contain ingredients such as dried fruit, bran, granola, rolled wheat, seeds and psyllium fiber. These ingredients provide several health benefits, including improving satiety, keeping blood glucose stable and improving bowel movements. However, the down side is that they may also cause constipation under certain circumstances. Not to worry; you don't have to give them up entirely. Just a few small changes to your diet can prevent this unpleasant symptom.

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Add Fiber Bars to Your Diet Gradually

One of the main causes of constipation related to eating fiber is increasing it too quickly in your diet. Ideally, women younger than 50 should consume at least 25 g. of fiber; after age 50, they should have about 21 g. daily, according to Leslie Beck, a registered dietitian and author of "The Complete A-Z Nutritional Encyclopedia." Men younger than 50 should consume 38 g. of fiber each day; after age 50, they should have 30 g. However, if you're not used to eating fiber, you don't have to try reaching this amount all at once. Instead, increase your intake of fiber gradually.


Drink More Water

Once you increase your fiber intake, you must also boost your water consumption. The amount of water each person needs differs. However, in general, non-pregnant, non-breastfeeding women should consume about 9 cups of water daily, recommends Beck. Men should consume about 12 cups. To make drinking more water easier, space it out throughout the day. For instance, drink a cup when you wake up in the morning, one cup with your fiber bar and one before a meal. Find a schedule that suits you; make it a habit.


Regardless of how much health professionals recommend that Americans eat more fiber, the average American consumes only 15 g. of fiber each day. Supplementing your diet with fiber bars can help you reach the recommended daily amounts. However, you should also be eating enough fiber-rich foods, such as fruits, vegetables and whole grains. In general, adults should consume at least 2 cups of fruits, 2 ½ cups of vegetables and three to five 1-oz servings of whole grains each day, according to the American Dietetic Association.



If you have a medical condition, such as irritable bowel syndrome or any other intestinal disorder, consult your doctor before taking fiber bars. Also, other symptoms may accompany constipation when you increase your fiber intake, including gas and flatulence. Eating small amounts of fiber throughout the day can help prevent these symptoms. After your body becomes used to the increased fiber on a regular basis, pesky adverse reactions from eating fiber bars should subside.


Is This an Emergency?

If you are experiencing serious medical symptoms, please see the National Library of Medicine’s list of signs you need emergency medical attention or call 911. If you think you may have COVID-19, use the CDC’s Coronavirus Self-Checker.
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