Fact or Fiction: Can Bananas Cure Diarrhea?

Submitted By Amy Sercel MS RD CD

Edited By Marcia Bristow MS RDN CSSD CD

Diarrhea is an uncomfortable topic.  People don’t really like to talk about it, even though everyone usually gets it a few times each year.  You might come down with diarrhea if you get the stomach flu, eat something you’re allergic or intolerant to (especially in the cases of lactose intolerance or celiac disease!), or eat food that’s contaminated with bacteria.¹ Diarrhea usually goes away on its own after a few days, but if it lasts for more than a week you should definitely see your doctor to make sure you don’t need antibiotics to fight off an infection.

Although many factors can lead to diarrhea, the discomfort it causes is basically a result of too much water in your intestines.  This can happen when water moves into your bowels to dilute the substance that’s giving you trouble, or when your intestinal cells secrete more fluid than usual because they’re irritated by bacteria or an allergen.² Either way, diarrhea will make you lose a lot of fluid, which can lead to dehydration and electrolyte imbalances.  When you’re experiencing diarrhea you should drink between eight and ten 8-ounce glasses of water each day and snack on foods that contain salt and potassium to make sure you stay hydrated until everything is back to normal.^1,3

In addition to drinking plenty of water, temporarily following the BRAT diet can also help you feel better.  This diet suggests eating bananas, rice, applesauce, and toast, which are all bland foods that contain a type of fiber known as indigestible starch.  This starch slows down digestion so you are able to absorb more water, vitamins, and minerals, and will not find yourself heading to the bathroom as often.  Indigestible starch also provides food for the “good” bacteria in your intestines, promoting their growth and helping to get rid of any “bad” bacteria that might be making you sick.^3,4

Bananas in particular are a well-known home remedy for diarrhea.⁵ One study found that patients with diarrhea improved within just 24 hours of eating a banana.  They were also less likely to need IV fluids for rehydration and recovered more quickly than patients who didn’t eat bananas.³ Since one banana contains about 422 mg of potassium, they also help prevent any electrolyte imbalances that can result from the loss of fluids and nutrients that goes along with diarrhea.^1,6

Some people suggest eating banana flakes or chips when you have diarrhea.  A ½ cup serving of dried bananas has more fiber and potassium than a fresh banana, so they can be a great alternative if you don’t want a fresh banana.  Banana flakes are very small pieces of dried bananas that you can mix into the batter of a baked good, or drink in a smoothie or glass of water.  They’re given to hospital patients with diarrhea and have been shown to help treat diarrhea in patients receiving tube feedings.⁷ If you want to try banana flakes, you can buy them online.  Depending on the brand you get, you might need to eat 4 tablespoons to get the equivalent of one banana.⁸ Follow the directions on the package to make sure you’re getting the right serving size of banana flakes.

If you decide to try banana chips instead of flakes, remember that banana chips are usually deep fried and sprinkled with sugar, which can worsen diarrhea and adds to their calorie content.^6,9 A ½ cup serving of store-bought banana chips might have 176 calories, 10 grams of saturated fat, and 12 grams of added sugar!¹⁰ On the other hand, a medium fresh banana or 4 tablespoons of banana flakes have between 80 – 100 calories, less than half a gram of fat, and no added sugar.^6,8  If you do want to eat banana chips, try baking them yourself to avoid the added sugar and fat.  Even if you’re not coming down with diarrhea, snacking on homemade banana chips or adding some banana flakes to your yogurt or smoothie can be a great way to get more potassium and fiber into your diet.

References:

1.         When you have diarrhea: MedlinePlus Medical Encyclopedia. https://medlineplus.gov/ency/patientinstructions/000121.htm. Accessed October 18, 2016.

2.         Whyte LA, Jenkins HR. Pathophysiology of diarrhoea. Paediatr Child Health. 2012;22(10):443-447. doi:10.1016/j.paed.2012.05.006.

3.         Rabbani GH, Teka T, Zaman B, Majid N, Khatun M, Fuchs GJ. Clinical studies in persistent diarrhea: Dietary management with green banana or pectin in Bangladeshi children. Gastroenterology. 2001;121(3):554-560. doi:10.1053/gast.2001.27178.

4.         Mitsou EK, Kougia E, Nomikos T, Yannakoulia M, Mountzouris KC, Kyriacou A. Effect of banana consumption on faecal microbiota: A randomised, controlled trial. Anaerobe. 2011;17(6):384-387. doi:10.1016/j.anaerobe.2011.03.018.

5.         Mom’s Advice Is Still the Best for Treating Diarrhea - Health Essentials from Cleveland Clinic. https://health.clevelandclinic.org/2014/12/moms-advice-is-still-the-best-for-treating-diarrhea/. Accessed October 18, 2016.

6.         Campbell M, Campbell M. Nutrition of Bananas vs. Dehydrated Bananas. LIVESTRONG.COM. http://www.livestrong.com/article/534188-nutrition-of-bananas-vs-dehydrated-bananas/. Accessed October 18, 2016.

7.         Emery EA, Ahmad S, Koethe JD, Skipper A, Perlmutter S, Paskin DL. Banana flakes control diarrhea in enterally fed patients. Nutr Clin Pract Off Publ Am Soc Parenter Enter Nutr. 1997;12(2):72-75.

8.         Nana Flakes 100% Pure Banana Flakes Banana Medical Food Powder. Amazon.com. https://www.amazon.com/Flakes-Banana-Medical-Powder-Pound/dp/B00T3JTZUA?th=1. Accessed October 18, 2016.

9.         Are Banana Chips Healthy? http://healthyeating.sfgate.com/banana-chips-healthy-3697.html. Accessed October 18, 2016.

10.       Oliver LM, Oliver LM. Dried Banana Chips Nutrition. LIVESTRONG.COM. http://www.livestrong.com/article/338951-dried-banana-chips-nutrition/. Accessed October 18, 2016.