You may already know that bananas are chock-full of potassium (one ripe banana supplies more than 10% of an adult’s daily requirement). It’s crucial to get enough potassium because people with a low dietary intake of the mineral are 28% more likely to suffer a stroke than those who consume higher levels, probably because adequate potassium levels help control blood pressure.
The other health benefits of bananas are less well-known. For example, as a good source of tryptophan (a precursor to serotonin, a brain chemical that helps regulate mood), bananas help fight depression. Bananas also are rich in the B vitamin folate—several epidemiological studies have linked low blood levels of folate and vitamins B-6 and B-12 to an increased risk for depression.
Research has not identified the optimal daily intake of bananas to fight depression, but anecdotal evidence suggests that eating two to three bananas (or other tryptophan sources, such as turkey and cottage cheese) daily—while maintaining a well-balanced diet and getting regular exercise—may help prevent mild-to-moderate depression.
In addition, bananas help fight heartburn by neutralizing acidity and soothing and coating esophageal tissue with pectin.
Important: In rare cases, bananas may cause an allergic reaction. Overly ripe bananas with blackened skin can increase blood sugar levels. People with kidney problems should check with their doctors before eating this potassium-rich fruit.
Source: Ara DerMarderosian, PhD, is professor of pharmacognosy (the study of natural products used in medicine) and Roth chair of natural products at the University of the Sciences in Philadelphia. He is coeditor of The Review of Natural Products (Lippincott Williams & Wilkins).