A Banana a Day Keeps the Doctor Away

It used to be an apple that was included in the often quoted phrase, but now it seems that there are reasons why bananas should get as high a profile. Bananas, potassium and heart disease may all be related. Bananas are different from many other fruits and vegetables in that they are a good source of potassium and low in sodium.

bananas by Alexandre Gacon

Sodium is an essential nutrient; we need it in our diets. Sodium is found in all extracellular fluids in our body and involved in a wide range of physiological reactions. Health regulatory officials have been recommending for some time that people reduce their salt (sodium chloride) intake to combat hypertension or high blood pressure and, consequently, reducing mortality from coronary heart disease and stroke. Sodium has also been implicated in increases in blood pressure with age. US officials have recommended a safe minimum level of 500 milligrams (mg) sodium per day and an upper level of 2,400 mg sodium per day.

Potassium is found in many parts of the body; it is involved in fluid and electrolyte balance. It has an important role in heart muscle activity and is found in many metabolic pathways. Epidemiological and animal studies indicate that the risk of stroke-related deaths is inversely related to potassium intake over the entire range of blood pressures and the relationship appears to be dose dependent. That means the higher the potassium intake, the lower the risk. US officials believe that a diet containing approximately 3.5g of potassium / day may contribute to reduced risk of stroke, which is especially common among blacks and older people of all races. The combination of a low-sodium, high potassium intake has been found to be associated with the lowest blood pressure levels and the lowest frequency of stroke in individuals and populations. High potassium and low sodium - that`s where the banana come in.

United States Food and Drug Administration has allowed the following health claim to be made for bananas: diets containing foods that are good sources of potassium and low in sodium may reduce the risk of high blood pressure and stroke. Bananas qualify for the health claim because they contain at least 350 mg of potassium and 140 mg or less of sodium (per normal serving). Bananas also are low in fat, low in saturated fat, and low in cholesterol.

Table 1: Banana Facts
Banana Facts
The plant:bananas do not come from a tree but a system of leafstalks growing inside one another
The fruit:it grows in bunches (weighing 27-45 kg) that are made up of clusters of fruit called hands which contain 12-20 bananas or fingers
Propagation:the plant bears only one crop; the plant is cut down and another spouts from the same root
Production:worlds largest producer of bananas - India 6.2,000,000 MT (1990); largest producer of plantains - Uganda 7.4, 000,000 MT (1990)
  1. Reference
  2. Food and Nutrition Encyclopaedia, 2nd Edition
  3. Health Claim Notification for Potassium Containing Foods3 FDA/CFSAN

Other articles on potassium §

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External Link Index 1 - http://vm.cfsan.fda.gov/~dms/hclm-k.html