Plantain
Plantains are a variety of banana, but unlike “eating bananas,” they do not convert their starches to sugar as they mature. Even ripe plantains must be cooked before serving.
The plantain is classified botanically as a vegetable; the banana is classified as a fruit. Nutritionally, the plantain has up to 14 times as much vitamin A, two times as much vitamin C, and one-third more potassium than the banana.
One-half cup boiled plantain slices has 2 g dietary fiber, 700 IU vitamin A (30 percent of the RDA for a woman, 24 percent of the RDA for a man), 8.4 mg vitamin C (11 percent of the RDA for a woman, 9 percent of the RDA for a man), and 358 mg potassium (72 percent as much potassium as eight ounces fresh orange juice).
NOTE: Unripe plantains, like unripe bananas, contain proteins that inhibit the actions of amylase, an enzyme required to digest starch and other complex carbohydrates.
 |
Cooked.
Controlled potassium diet
Look for: Large, firm plantains with green peel flecked with some brown spots. The riper the plantain, the blacker its skin.
Avoid: Plantains with soft spots under the skin.
Store plantains at room temperature or refrigerate.
Cut off the ends of the plantain, slice down through the peel and remove it in strips, under running water to prevent the plantain from staining your hands.
When you cook a plantain the starch granules in its flesh will swell and rupture. The fruit softens and its nutrients become easier to absorb.
Potassium benefits. Because potassium is excreted in urine, potassium-rich foods are often recommended for people taking diuretics. In addition, a diet rich in potassium (from food) is associated with a lower risk of stroke. A 1998 Harvard School of Public Health analysis of data from the long-running Health Professionals Study shows 38 percent fewer strokes among men who ate nine servings of high-potassium foods a day vs. those who ate less than four servings. Among men with high blood pressure, taking a daily 1,000 mg potassium supplement—about the amount of potassium in 11/2 cups sliced plantain—reduced the incidence of stroke by 60 percent.
Lower risk of stroke. Various nutrition studies have attested to the power of adequate potassium to keep blood pressure within safe levels. For example, in the 1990s, data from the long-running Harvard School of Public Health/Health Professionals Follow-Up Study of male doctors showed that a diet rich in high-potassium foods such as bananas, oranges, and plantain may reduce the risk of stroke. In the study, the men who ate the higher number of potassium-rich foods (an average of nine servings a day) had a risk of stroke 38 percent lower than that of men who consumed fewer than four servings a day. In 2008, a similar survey at the Queen’s Medical Center (Honolulu) showed a similar protective effect among men and women using diuretic drugs (medicines that increase urination and thus the loss of potassium).
Improved mood. Bananas and plantains are both rich in serotonin, dopamine, and other natural mood-elevating neurotransmitters—natural chemicals that facilitate the transmission of impulses among nerve cells.
Digestive problems. Unripe plantains, like unripe bananas, contain proteins that inhibit the actions of amylase, an enzyme required to digest starch and other complex carbohydrates.
False-positive test for carcinoid tumors. Carcinoid tumors, which may arise from tissues of the endocrine system, the intestines, or the lungs, secrete serotonin, a natural chemical that makes blood vessels expand or contract. Because serotonin is excreted in urine, these tumors are diagnosed by measuring the levels of serotonin by-products in the urine. Plantains contain large amounts of serotonin; eating them in the three days before a test for an endocrine tumor might produce a false positive result, suggesting that you have the tumor when in fact you don’t. Other foods high in serotonin are avocados, bananas, eggplant, pineapple, plums, tomatoes, and walnuts.
