Health Benefits of Bananas

Reading time: 6 – 9 minutes

My daughter loves Bananas, as do I. We both eat one for breakfast everyday. Not only do bananas taste great, but they provide a number of health benefits for children. A study published in the American Journal of Epidemiology a few years ago showed an association between regular consumption of bananas/oranges and orange juice in children from ages 0-2 and a reduction in the risk of childhood leukemia diagnosed between the ages of 2 and 14 years [1]. The results suggested that fruits or fruit juices containing vitamin C and/or potassium may reduce the risk of childhood leukemia, especially if they are consumed on a regular basis during the first 2 years of life. A separate study published this year found evidence that a higher consumption of bananas and apple juice from concentrate may protect against wheezing in children [2].

For children and adults, bananas can help overcome or prevent a number of health conditions, making it a must to add to our daily diet.

Bananas are high in fiber. A single banana contains 16% of the dietary fiber, 15% of the vitamin C, 11% of the potassium and 20% of the vitamin B6 recommended each day [3]. There are two types of fiber, divided according to whether they are water-soluble or not. Soluble fiber is found in certain fruits, beans, peas, legumes and oats, and may help lower blood cholesterol and reduce the risk of heart disease and stroke [4-5]. Insoluble fiber is found in whole wheat, wheat and corn bran, flax seed lignans (meaning class of phytoestrogen, which is an antioxidant) and vegetables such as carrots, celery, green beans and potato skins. Insoluble fiber provides the bulk needed for proper functioning of the stomach and intestines.

Eat a banana if you suffer from heartburn. Bananas have a natural antacid effect in the body. Scientific studies in rats have shown that Bananas help to make the lining of the stomach hydrophobic (meaning repels water) by adsorption of phospholipid (meaning a class of organic compounds that are soluble in nonpolar solvents such as ether or chloroform and are relatively insoluble in water) stored in secretory cell compartments of the fruit [6]. Additionally, Bananas have anti-ulcerogenic properties. A flavonoid (meaning class of plant secondary metabolites known for their antioxidant activity) in the banana, leucocyanidin, has been found to significantly increase the thickness of the mucous membrane layer of the stomach [7].

Snacking on bananas between meals helps to keep blood sugar levels up. The glycemic index rating for a ripe, yellow banana is 51 with a glycemic load rating of 12.2 [8]. These numbers are good – the carbohydrates in a banana have a medium to slow effect raising blood sugar levels. However, as bananas ripen, the starch in the fruit turns to sugar; this will negatively affect the gylcemic response [9]. Another way to view this is that when bananas are a slight green/yellow, they impact the blood glucose level less than when they are fully yellow and starting to brown.

Bananas can help to counter stress. Indeed, a banana a day could prevent a deficiency of potassium, which might increase the risk of stroke. Recent studies suggest that potassium might influence the risk of a stroke through several mechanisms that involve vascular biology. Dietary potassium seems to be the most important marker among nonusers of diuretics (meaning any drug or herb that elevates the rate of bodily urine excretion), suggesting that increased water excretion prevents the potassium from being absorbed by the body [10-11]. Potassium is an essential mineral needed to regulate water balance, acidity level and blood pressure. Classified as an electrolyte (meaning a solution that conducts electricity), potassium is used by cells in the body to regulate electrical charge and flow of water molecules across cell membranes. A lack of potassium may cause muscle weakness, irregular heartbeat, nausea or vomiting. Keep in mind however that potassium is the predominant nutrient among most fruits and vegetables. Unless you’re not eating any other fruits or vegetables, you don’t need to eat bananas for the potassium.

Some interesting facts:

• The banana plant is in the same class (Lilliopsida or Monocot) as the lilly and orchid.
• The main section of the banana plant is called a pseudostem. Each pseudostem produces a single bunch of bananas before dying back to the root. A new pseudostem then grows to produce another bunch of bananas.

References

1. Kwan et al. Food consumption by children and the risk of childhood acute leukemia. Am J Epidemiol. 2004 Dec 1;160(11):1098-107.
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2. Okoko et al. Childhood asthma and fruit consumption in South London. Eur Respir J. 2007 Feb 14; [Epub ahead of print].
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3. The International Banana Association
4. Bazzano et al. Legume consumption and risk of coronary heart disease in US men and women: NHANES I Epidemiologic Follow-up Study. Arch Intern Med. 2001 Nov 26;161(21):2573-8.
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5. Liu et al. A prospective study of dietary fiber intake and risk of cardiovascular disease among women. J Am Coll Cardiol. 2002 Jan 2;39(1):49-56.
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6. Hills and Kirwood. Surfactant approach to the gastric mucosal barrier: protection of rats by banana even when acidified. Gastroenterology. 1989 Aug;97(2):294-303.
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7. Lewis and Shaw. A natural flavonoid and synthetic analogues protect the gastric mucosa from aspirin-induced erosions. J Nutr Biochem. 2001 Feb;12(2):95-100.
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8. The Official Website of the Glycemic Index and GI Database
9. Hermansen et al. Influence of ripeness of banana on the blood glucose and insulin response in type 2 diabetic subjects. Diabet Med. 1992 Oct;9(8):739-43.
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10. Green et al. Serum potassium level and dietary potassium intake as risk factors for stroke. Neurology. 2002 Aug 13;59(3):314-20.
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11. Levine and Coull. Potassium depletion as a risk factor for stroke: will a banana a day keep your stroke away? Neurology. 2002 Aug 13;59(3):302-3.
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