A Banana Every Day Could Keep High Blood Pressure Away

Study Finds ^ | April 15, 2025 | Melissa Stadt, University of Waterloo

[Red Badger]

In a nutshell

Potassium can lower blood pressure, even on a salty diet. Simulations showed that increasing potassium intake significantly reduced blood pressure, even when sodium levels stayed high, with drops of up to 14 mmHg in men and 10 mmHg in women.

Men and women respond differently to potassium. The models revealed that female kidneys handle sodium differently, offering natural protection against high blood pressure, while men showed a stronger blood pressure response to dietary potassium.

Balancing potassium and sodium may matter more than cutting salt alone. The study suggests that boosting potassium-rich foods like leafy greens, beans, and sweet potatoes could be a powerful, underused strategy for managing blood pressure.

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WATERLOO, Canada — Want to lower your blood pressure? Skip the salt shaker and reach for a banana instead. A new study reveals that boosting your potassium intake might be a powerful way to combat high blood pressure.

Scientists from the University of Waterloo in Canada found that high-potassium diets can significantly reduce blood pressure, even when you’re still consuming a fair amount of salt. This study, published in the American Journal of Physiology-Renal Physiology, challenges what we’ve long believed about managing hypertension and suggests potassium deserves more attention in our dietary choices.

High blood pressure affects millions of people worldwide and remains the leading cause of heart disease and premature death. Its prevalence has been climbing in recent years, thanks in part to our aging population and lifestyle changes, particularly our love affair with processed foods that are typically loaded with salt but lacking in potassium.

How Potassium Fights High Blood Pressure

Using computer simulations showing hypertension scenarios, researchers found that doubling potassium intake reduced blood pressure by up to 14 mmHg in men and 10 mmHg in women. To put that in perspective, many blood pressure medications aim to reduce readings by similar amounts.

Potassium’s beneficial effects continued even when salt consumption remained high. This suggests that you might be able to partially offset the harmful effects of that salty pizza or bag of chips by making sure you’re also eating plenty of potassium-rich foods.

Instead of testing these theories on human subjects, the researchers built complex mathematical models that simulate how the body responds to different mineral intakes. These computer models captured the intricate dance between the kidneys, heart, nervous system, and hormones involved in blood pressure regulation.

It’s well known that women typically have lower blood pressure than men of the same age before menopause, and these simulations helped identify why that is the case.

The research team found that women’s reduced response to hypertension triggers, including high salt intake, appears to be largely because of the different way female kidneys transport sodium, giving women some natural protection against blood pressure spikes.

In the short term, when you consume potassium-rich foods, your digestive system sends immediate signals to your kidneys before your blood potassium levels even change. This “feedforward” system triggers increased potassium excretion in urine, helping prevent dangerous spikes in blood potassium.

Blood pressure meter and heart

Research shows incorporating more potassium into your diet can effectively lower blood pressure. (New Africa/Shutterstock) In the longer term, high potassium intake causes your kidneys to decrease sodium reabsorption in multiple parts of their filtering units. This leads to greater sodium excretion, reducing fluid volume in your blood vessels and consequently lowering blood pressure. This explains why potassium can help offset the effects of high-sodium diets: it essentially helps your body eliminate more sodium through urine.

Balancing Your Diet for Heart Health

Loading up on potassium-rich foods like sweet potatoes, spinach, avocados, and white beans could be a simple dietary approach to help keep your blood pressure in check. The ratio of potassium to sodium might matter more than your total sodium intake alone, emphasizing the importance of a balanced diet.

And, because men and women respond differently to dietary changes and potentially to blood pressure medications, doctors might need more personalized approaches when treating hypertension.

Overall, consuming more fruits and vegetables while limiting processed foods is a great first step. The potassium-rich diets our ancestors ate likely protected them from hypertension, even with relatively high salt intake, a balance that modern eating habits have increasingly disrupted.

Paper Summary

Methodology

The researchers created sex-specific computer models to simulate how sodium, potassium, and fluid balance affect blood pressure throughout the body. These models accounted for known biological differences between males and females, including kidney function, hormone levels, nervous system activity, and blood vessel responses. The models captured interactions among the kidneys, heart, digestive system, and various regulatory systems. They then ran simulations with different combinations of sodium intake, potassium intake, and various types of hypertension to see how these factors affect blood pressure differently in men versus women.

Results

The simulations showed that high sodium intake raised blood pressure in both sexes, but the effect was smaller in females. When potassium intake was doubled, blood pressure decreased significantly—by up to 14 mmHg in males and 10 mmHg in females with certain types of hypertension. Notably, higher potassium intake counteracted the blood pressure-raising effects of high sodium intake. Women’s different kidney transporter pattern appeared largely responsible for their protection against hypertension, as they reabsorb less sodium in the early parts of the kidney filtering system. High potassium intake triggered several kidney adaptations that lowered blood pressure, including reduced sodium reabsorption in both early and later portions of the kidney tubules, increasing sodium excretion.

Limitations

The study used computer models rather than actual human subjects, and had to extrapolate some sex-specific parameters from rat studies due to limited human data. The models represent normal blood pressure or mild hypertension conditions and may not apply to severe hypertension. The researchers acknowledged their representation of the hormone system involved in blood pressure regulation was simplified, potentially underestimating sex differences. Additionally, the models didn’t explicitly account for nitric oxide or oxidative stress, which show sex differences and play important roles in blood pressure regulation.

Funding and Disclosures

This research was partially funded by the Natural Sciences and Engineering Research Council of Canada. The authors declared no conflicts of interest.

Publication Information

The study titled “Modulation of blood pressure by dietary potassium and sodium: sex differences and modeling analysis” was authored by Melissa Stadt and Anita T. Layton from the University of Waterloo, Ontario, Canada. It was published in the American Journal of Physiology-Renal Physiology (Volume 328, pages F406-F417) in 2025, first published online on October 24, 2024.

[Red Badger]

I do, I take potassium supplements, 2% RDA, twice a day at meal time. Plus bananas, leafy greens and potatoes..............

[telescope115]

Thanks for the info. Must buy more bananas.

[glorgau]

Durian is also high in potassium.

[Red Badger]

Durian?...............

[Big Giant Head]

Avocados. More potassium than bananannananas.

[catnipman]

“Tired of taking pills that sap my energy.”

beta blockers will do that ... if that’s what you’re taking, you might want to talk to your doc about switching to an ARB, the class of BP meds with the lowest side-effect profile ... most are generic now, so relatively inexpensive ...

[Red Badger]

A whole medium avocado typically has around 225 to 300 calories, depending on its size. A medium-sized banana contains approximately 105 calories..............

[catnipman]

the role potassium plays in BP is well known:

https://www.google.com/search?q=kidney+elimination+of+sodium+tied+to+potassium

also, lots of other foods are high in potassium without the sugar contained in bananas:

https://www.google.com/search?q=best+source+of+potassium

[Karoo]

FYI

The Recommended Dietary Allowance (RDA) of potassium for adults is 2,600 to 3,400 mg per day, depending on age and gender.

[glorgau]

> Durian?...............

Yes, Durian the king of fruits.

[Red Badger]

Had to look it up.

We don’t get much call for that around these parts..............

[Ge0ffrey]

But bananas 🍌 make it hard to poop.

[Red Badger]

I’ve never heard of that.....................

[Ge0ffrey]

Yes, they’re binding.

[Ge0ffrey]

The BRAT Diet

BRAT stands for bananas, rice, applesauce and toast, which are all bland, soft, low-fiber foods that can help alleviate diarrhea and even reduce your risk of developing dehydration.

All of the foods in the BRAT diet are classified as binding foods because they can help solidify your stool and decrease diarrhea. They’re also easy to digest, so they typically don’t put extra strain on your body and can help you hold down your food if vomiting is an issue.

Eating a banana for diarrhea is especially helpful because, in addition to its easy digestibility, bananas are high in potassium. When you have chronic and persistent diarrhea, potassium is one of the electrolytes that’s expelled from your body in large volume. Bananas can help replace that lost potassium and reduce your risk of dehydration.

[Red Badger]

Never had that problem and I eat bananas practically every day..............

[Ancesthntr]

I suppose that having a banana a day would help with high blood pressure on a national basis. Medium banana contains around 375 mg of potassium, which is something like 1/8 of what people actually need. However, the negatives of consuming a banana include the fact that they are loaded with sugars, and will lead to pre-diabetes and diabetes among many people. Simple fact is that there are many foods which contain more potassium Than bananas, and quite a number of them do not significantly elevate blood sugar levels. See the following article: https://www.health.com/foods-with-more-potassium-than-a-banana-11708177

Additionally, and perhaps even better, would be to have a shaker full of potassium chloride, rather than one filled with sodium chloride (IOW, salt) on your table. I routinely put a shake or two of this on many of the foods that I eat. No, it does not taste exactly like salt, but it is very close and it is very easy to get accustomed to it. I figure that between not adding salt to my diet as much as I used to, consuming avocados, and adding potassium as I have just described, I am getting pretty much everything that I need without jacking up my blood sugars.

[Tammy8]

I used to eat a banana every day. Now it is hard to find decent bananas. I want yellow bananas and they are sold green now. Produce guy told me when they are green they are better for you. I don’t like them and they seem to rot as soon as they barely turn yellow.

[Faith65]

Thanks
BKMK

[Fungi]

Potassium rich foods
Swiss chard, 1 cup cooked (960 mg)

Spinach, 1 cup cooked (840 mg)

Avocado, 1 cup (708 mg)

Sweet potato, medium (700 mg)

Bok choy, 1 cup cooked (630 mg)

Potato, medium (610 mg)

White beans, 1/2 cup (600 mg)

Beets, 1 cup (520 mg)

Brussels sprouts, 1 cup cooked (500 mg)

Broccoli, 1 cup cooked (460 mg)

Cantaloupe, 1 cup (430 mg)

Banana, 1 medium (420 mg)