Can a banana a day control blood pressure and reduce the risk of heart disease?

Bananas are a popular fruit with a sweet and smooth taste. Many people cannot resist any banana-flavored food, and some people even eat one banana a day!

What nutrients does banana have? What are the benefits of eating it every day? In this article, let’s talk about bananas and learn more about them.

01 Nutrition of banana

Bananas have a smooth and thick texture that melts in your mouth, and have a special and attractive aroma, which is the main reason why many people love to eat bananas. This aroma mainly comes from amyl acetate and other ester substances. As for the nutritional value of bananas, there are some that are more prominent.

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•Potassium: The potassium content of bananas is 256 mg/100 g, which is higher than most common fruits , such as peaches, oranges, plums, watermelons, cantaloupes, etc., and more than three times that of apples.

•Magnesium: The magnesium content of bananas is 43 mg/100 g, which is 10.7 times that of apples.

•Dietary fiber: Although the dietary fiber content of bananas is not as high as that of kiwi, avocado, Korla pear, guava and other fruits, it is still medium among fruits, with a total dietary fiber content of 2.6 grams/100 grams and an insoluble dietary fiber content of 1.2 grams/100 grams.

•Carbohydrates: The carbohydrate content of bananas ranks at the top among commonly eaten fresh fruits, second only to fresh dates, plantains, durian, winter dates, and jackfruit.

Other nutrients such as vitamin C, B vitamins, calcium, zinc, carotene, etc. are not abundant .

02 What are the benefits of eating bananas?

Since bananas are nutritious, what effect will eating one banana a day have on the body?

1. Control blood pressure : Sufficient potassium intake in the diet has a significant effect on reducing high blood pressure caused by high sodium ; magnesium intake is negatively correlated with high blood pressure, and magnesium supplementation can reduce vascular tension and vascular tone. Because bananas are rich in potassium and magnesium, eating bananas regularly is helpful in improving blood pressure.

Eating a banana with 150 grams of edible part every day can provide 348 mg of potassium and 65 mg of magnesium, which can respectively meet 17% and 20% of the daily needs of the general population.

In addition, adequate potassium can help reduce neuromuscular tension and relieve fatigue .

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2. Reduce the risk of heart disease : A study published in the European Heart Journal showed that eating more potassium-rich foods can improve heart health and prevent heart disease. The study showed that during the nearly 20-year follow-up period, those with the highest potassium intake had a 13% lower risk of cardiovascular events compared to those with the lowest potassium intake. The risk of cardiovascular disease occurrence or recurrence in women was reduced by 11%, and in men by 7%.

Additionally, increasing your intake of potassium-rich foods may reduce your risk of stroke.[5]

3. Rapid energy replenishment : Bananas have a low water content, and eating just one banana will give you a strong sense of fullness. Its calorie and carbohydrate content are relatively high among common fruits. It contains sucrose, glucose and fructose, with glucose and fructose being the main components. It can quickly replenish energy and sugar for the human body and restore body functions. Moreover, the glycemic index (GI) of bananas is only 52, which is a low-GI fruit, and eating it will not cause a significant increase in blood sugar.

4. Reduce the risk of constipation : For people who suffer from constipation due to insufficient dietary fiber intake, eating bananas can help with bowel movements. Although bananas are not as effective as fruits such as prunes, pears, and dragon fruits in promoting bowel movements, they are still quite effective compared to fruits such as apples, peaches, and oranges. Eating a banana with 150 grams of edible part every day can intake nearly 4 grams of dietary fiber.

It is important to note that if you want to prevent constipation and promote bowel movements, you must choose ripe bananas . If you eat unripe bananas, the tannic acid in them has an astringent effect and will aggravate constipation. Generally speaking, if black spots appear on the surface of the banana peel and it feels soft, it is basically ripe.

However, those who want to lose weight should note that bananas are high in calories, so don’t be too extravagant or you may get fat !

03 Do bananas contain radiation and cause cancer?

Bananas, despite their many benefits, cannot escape being blamed for rumors. There is a rumor that bananas are the fruit with the highest radiation and should not be eaten because they can cause cancer. Is this true?

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In fact, this rumor is half right and half wrong. Bananas do have radiation, but it is nothing to be afraid of .

The reason why bananas have radiation is mainly because their potassium-40 content is relatively high among fruits. Although potassium-40 is a type of ionizing radiation (CT examinations and nuclear radiation are both ionizing radiation), the dose determines the toxicity after all.

The additional ionizing radiation dose brought by eating one banana is about 0.0778 microsieverts (a unit of calculation of radioactive dose), while the ionizing radiation dose of a lung CT chest radiograph is about 7 millisieverts. In comparison, this is equivalent to eating 90,000 bananas.

In other words, there is no need to worry about the radiation in a banana. If you want to eat bananas to the extent that ionizing radiation can harm your body, you will probably burst your stomach first . There is no need to worry about this radiation accumulating in the body. The radioactive potassium element will be excreted from the body through metabolism, so there is no need to worry.

Besides, the lead-210 and polonium-210 contained in cigarettes are also radioactive elements. For smokers, if they smoke 20 cigarettes a day, the annual dose of polonium-210 that enters the lung tissue with the smoke is 0.46 millisieverts, which is equivalent to 5,900 bananas. If you are worried, then you should quit smoking first!

04 How to preserve bananas?

If the bananas you bought are a little raw, don't rush to eat them. You can put them in an environment of about 20℃ to let them ripen by themselves . At this temperature, bananas have normal respiration and ethylene release peak. The chlorophyll content in the peel gradually decreases and the carotenoid content gradually increases, and the peel will gradually change from green to yellow.

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Although the higher the temperature, the faster the bananas will ripen, in an environment above 25°C, the bananas may ripen with green skin. This is because when the storage temperature exceeds 25°C, it will inhibit the degradation of pheophytin and pheophorbide in the banana peel, which will seriously affect the process of the peel turning from green to yellow, resulting in "green skin ripening".

It is best to buy a small amount of bananas at a time and store them in a cool and ventilated place indoors, preferably at 14-20 degrees Celsius. If you buy too much, it is best not to put them in the refrigerator, because 11-13 degrees Celsius is the critical temperature for bananas to suffer from chilling damage, and the refrigerator temperature is only 0-4 degrees Celsius, which will cause frostbite.

In short, bananas are easy to carry and can be eaten directly without washing or peeling. However, they are not suitable for large-scale stockpiling . Although eating one banana a day is nutritious, don’t just indulge in bananas. Fruits should also be eaten equally!

References

[1] Harold Mackey, Food and Cooking: Vegetables, Fruits, Spices, and Grains. Translated by Cai Chengzhi. Beijing Fine Arts Photography Publishing House. August 2013.

[2] Yang Yuexin. Chinese Food Composition Table 6th Edition Volume 1[M]. Peking University Medical Press, 2018

[3] https://fdc.nal.usda.gov/fdc-app.html#/food-details/173944/nutrients

[4]Women urged to eat potassium-rich foods to improve their heart health. ESC. 22 Jul 2022.

[5]Aburto NJ, Hanson S, Gutierrez H, Hooper L, Elliott P, Cappuccio FP. Effect of increased potassium intake on cardiovascular risk factors and disease: systematic review and meta-analyses. BMJ. 2013 Apr 3;346:f1378. doi: 10.1136/bmj.f1378. PMID: 23558164; PMCID: PMC4816263.

[6] Tong Hanqing, Hai Jinping, Li Shuchang, et al. Optimization of ultrasound-assisted solvent extraction of 5-hydroxytryptamine from banana by response surface methodology[J]. Food Research and Development, 2020, 41(20): 124-130.

[7] Wang Xin, Chen Xing'an, Pan Yingdong. Study on the content of polonium-210 in cigarettes and its dose to human lung tissue[J]. Chinese Journal of Radiation Health, 2000(03):129-133.DOI:10.13491/j.cnki.issn.1004-714x.2000.03.001.

[8] Qi Wencai, Wu Ning, Zhang Liang, et al. Research progress on postharvest physiology and storage and preservation of banana[J]. Journal of Henan Normal University (Natural Science Edition), 2019, 47(03): 99-105. DOI: 10.16366/j.cnki.1000-2367.2019.03.016.

Author: Xue Qingxin, one of the first nutrition instructors of the National Health Commission, and a registered nutritionist in China

Review | Ruan Guangfeng, Deputy Director of Kexin Food and Health Information Exchange Center