Posted by Eric Troy on 25 Nov 2013 20:31
A viral internet post (probably email beginnings) that says "After reading this, you'll never look at a banana the same way again," lists a lot of supposed health benefits of bananas, including preventing anemia, depression, constipation, hangovers, morning sickness, etc.
It also claims that bananas calm the nerves and boost brain power.
As is usually the case with these kind of superfood messages, most of the claims, whether true or not, have to do with specific nutrients for which bananas boast a high level.
Therefore, any other food that is high in these nutrients should have the same benefits, at least as far as the logic of the message goes.
However, one item in the post makes a very specific, but less than genuine, claim about bananas.
This claim is about the ability of bananas to prevent and to treat high blood pressure.
Blood Pressure: This unique tropical fruit is extremely high in potassium, yet low in salt, making it perfect to beat high blood pressure. So much so, the U.S. Food and Drug Administration has just allowed the banana industry to make official claims for the fruit's ability to reduce the risk of blood pressure and stroke.
Is this true? Did the FDA become so enamored of bananas that the agency allowed the banana industry to make these claims about its effect on blood pressure? That would be a big, fat, NO. The FDA made no specific allowances for bananas, at all. Instead, a health claim is allowed by the FDA, for foods that contain 10% or more of the RDA of potassium. These eligible foods may use this health claim, exactly as it is stated here:
Diets containing foods that are good sources of potassium and low in sodium may reduce the risk of high blood pressure and stroke.
The banana industry had nothing to do with this health claim. They were just a possible recipient of its benefits. The FDA, as well, does not actually come up with these health claims. Instead, manufactures can submit a notification of a health claim to the FDA, based on an authoritative statement from an appropriate scientific body of the United States Government or the National Academy of Sciences (NAS), or any of its subdivisions. The FDA will then decide whether to prohibit or modify the proposed claim, and, if the agency does not prohibit or modify the claim, it may be used 120 days after the receipt of the notification.
The notification about a health claim for potassium-containing foods was submitted to the agency by Tropicana Products, Inc. on July 3, 2000, citing two statements from the NAS report, Diet and Health: Implications for Reducing Chronic Disease Risk, as authoritative statements for the claim. The two statements are:
- Statement 1: "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. The combination of a low-sodium, high potassium intake is associated with the lowest blood pressure levels and the lowest frequency of stroke in individuals and populations. Although the effects of reducing sodium intake and increasing potassium intake would vary and may be small in some individuals, the estimated reduction in stroke-related mortality for the population is large."
- Statement 2: "Vegetables and fruits are also good sources of potassium. A diet containing approximately 75 mEq (i.e., approximately 3.5g of elemental potassium) daily may contribute to reduced risk of stroke, which is especially common among blacks and older people of all races. Potassium supplements are neither necessary nor recommended for the general population."
The FDA did not act to modify or prohibit the claim, which caused manufacturers to be allowed to use the claim after October 31, 2000. After this went into affect, the banana industry, and others interested in touting the benefits of bananas, started saying that "a health claim has been allowed for bananas." Instead, a health claim was allowed for any food containing 10% or more of the RDA for potassium. This would not make bananas special, in any way.
The RDA of potassium is 4,700mg for 13 year olds to adults, which is 4.7 grams. One good sized banana can indeed supply 10% or a bit more of the RDA of this nutrient (although now RDI's are in vogue). But orange juice, alas, is an even better source, at a serving of only one cup. However, neither of them hold a candle to a cup serving of common beans, such as Lima (over 900mgs), pintos, split peas, kidney beans, black eyed peas, etc. And other fruits such as pears, cantaloupe, watermelon, and tomatoes, will give you more potassium per serving. That's not to mention a lowly baked potato, which can have near twice as much potassium as a banana. Then there's asparagus, beets, butternut squash, bok choy, and, wait, two cups of milk and you've hit your 10%. I could go on, but the point is that the banana industry has no real reason to be riding a high horse of a health claim concerning potassium.
A previous hypertension health claim had been allowed for low sodium foods, that allowed a statement indicating low sodium foods that met the criteria could claim a reduced risk of hypertension, or high blood pressure. The banana industry had been quick to point out that bananas qualify for this claim because they are low sodium, as if bananas belong to an exclusive and limited list of foods that meet the claim. In fact, fruits are, as a group, low sodium. They are the lowest sodium foods in the human diet! A previous claim concerning high fiber, low saturated fat, and coronary heart disease, is similar.
Incidentally, the company that started the ball rolling on the potassium health claim, got into hot water with the FTC for making claims far beyond the limited claim for potassium given above. PepsiCo, the owners of Tropicana made some far out claims in a series of advertisements between 2002 and 2004 like:
- Drinking three cups of Tropicana orange juice a day for four weeks will raise HDL cholesterol by 21 percent and improve the ratio of HDL to LDL cholesterol by 16 percent
- Drinking 20 ounces of Tropicana orange juice a day will increase blood levels of folate by almost 45 percent and decrease homocysteine levels by 11 percent
- Drinking two cups of Tropicana orange juice a day for six to eight weeks will lower systolic blood pressure an average of 10 points.
As you can see, the last statement concerning blood pressure is very specific and is NOT the health claim allowed, nor would such a specific claim have been allowed. The other claims do not have anywhere near the scientific support the company claimed. A settlement was reached and the company was banned from making such statements in the future, under threat of a civil penalty of $11,000. The company said that its agreement was not an admission that they had broken any laws.
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