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Bananas for Cancer: Do Brown Spots on Bananas Fight Cancer?

IMPORTANT UPDATE: The study on the TNF in bananas to cure cancer has actually been debunked on the basis that there is no written evidence proving that the study actually took place. Who is this "Professor Senji" of Tokyo University? There is no evidence that he even exists! Did someone make up this whole study from scratch? If so, what's there to gain by making up such information?

So many people now believe that bananas can cure/prevent cancer - yet there is no such evidence whatsoever. Are you now going to stop eating bananas? Please answer in the comments below!

Going Bananas to Fight Cancer

When bananas over-ripen, they develop dark brown spots on their yellow skin, become soft and mushy inside and emit a pretty strong ripe banana scent. At this stage, you probably think it’s time to toss them in the trash. But stop! Did you know that over-ripe bananas with brown spots on them actually help fight cancer?


Japanese Studies on Bananas for Cancer

A study was carried out in Tokyo University, Japan by Professor Senji, where lab mice were injected with extracts from a variety of fruits, including bananas. In this controlled experiment, it was found that out of all the fruit injected into the mice, banana marked the most improvements in the overall health of the mice. Bananas not only boosted the white blood cell count in the blood, but also inhibited the growth of cancer cells through inducing their bodies to produce a powerful substance called TNF.

When consumed, over-ripe bananas enable the body to produce a potent substance that is known to prevent and fight cancer. This natural miracle substance is known as the Tumor Necrosis Factor (TNF).

Eat the Spotty Bananas

Japanese are known to eat over-ripe bananas with brown spots regularly. But if they fall sick, they will go ahead and eat the really ripened bananas which have turned fully black. This habit is fully backed by research which proves that over-ripe bananas are rich in anti-oxidants and give the body the ability to produce TNF.

Tumour Necrosis Factor (TNF) in Bananas

Scientifically speaking, TNF is a cytokine consisting of small signalling molecules, which have a complex system to communicate with and influence fundamental cell activities and movements.

Simply put, TNF is a protein with the ability to correspond with cells and regulate their cellular activities and coordinate their movement. This is why TNF actually inhibits the development of abnormal cells, i.e. cancerous cells.

As minuscule as the small TNF molecule may seem, it has powerful functions that serve the body. Most importantly, TNF is useful in preventing cancer because it has the ability to destroy certain groups of tumour causing cells, by pumping excess water into the harmful cells and causing them to burst from the pressure.

Do brown spots on bananas fight cancer?

The Spottier, the Better!

The more brown spots a banana has, the more cancer-fighting properties it has.

Anti-oxidants in Bananas

Bananas contain a few antioxidants which destroy free radicals. Free radicals are those molecules that ravage through the blood stream causing the formation of cancerous cells. By destroying free radicals, the antioxidants in bananas are able to minimise free radical damage in the body and fight cancer in its early stages.

Bananas keep you Happy

And we all know that happy = disease-free. All diseases are created in the mind first. By maintaining tip-top mental health you can guarantee yourself a disease-free life. Bananas are among the top 10 foods that are known to boost your mood, as they contain nutrients that release endorphins in the brain, alleviate anxiety and ward off depression. Bananas keep you happy and help maintain your mental health, thus ensuring that you stay cancer-free.


Bananas and Constipation

  • Do Bananas Cause Constipation?
    Bananas are in a bit of a conundrum, being known by some to cause constipation while others swear bananas cure constipation! In this article we will find out do bananas cause constipation?

Eating Bananas Daily can boost your Immunity & Fight Cancer

Did you know, as per the research findings, the Japanese professor deduced that over-ripe bananas with brown spots on them have up to 8 times more white blood cell boosting abilities than under-ripe bananas.

The stronger your white blood cells, the stronger your immune system.

By eating 1 to 2 bananas a day, you can boost your immunity and strengthen your resistance against the common cold and throat infections



Please note, healthmunsta is not a medical doctor. The information contained in this article is purely for informational purposes only. There are many known and unknown causes of cancer. Simply eating over-ripe bananas may not prevent or even cure your cancer. As always, consult with your medical professional before undertaking any new dietary changes and if you are experiencing any disease-related symptoms.


Drgnmom on September 17, 2016:

But bananas also have a very high glycemic index, sugar content, and I understand that cancers thrive on sugars.

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healthmunsta (author) on April 05, 2015:

Thank you so much, Jack! You just brightened up my day! I'll need to edit in your links to this article. Are you working on a paper of your own in this topic? Perhaps you can get in touch with me and we can exchange more info on this topic?

Jack on April 05, 2015:

Third time is the charm !!! I do not know why the links above are not correct in my last 2 comments. Please delete those comments as they are not accurate and contain bad links.

Above is a link to the actual research conducted on the "Differences in Biological Response Modifier-like Activities According to the Strain and Maturity of Bananas". This research was not done by Professor Senji, but was done by Professor's Haruyo iwasawa and Masatoshi Yamazaki at the Department of Medical Life Chemistry, Faculty of Pharmaceutical Sciences, Tokyo University, Japan.

I think it is important to note that this research does not show that this is a cure for cancer, but there appears to be evidence that it can help to prevent abnormal cell growth.

I am including a translation of a synopsis I found of what this research implies. I also have included a link to this information.


According to modern medical research, bananas are rich in magnesium, and magnesium efficacious cancer prevention. In 1986, the Cancer Research Institute of the Chinese Academy of Medical Sciences found that banana extract has anti-carcinogenic three substances: aflatoxin B1, 4-nitroquinoline-N-oxide, phenylpropionate (a) pyrene, have significantly inhibit function.

Based on research by Japanese scientists found that substances in bananas have anticancer effects of TNF. In addition, the more ripe bananas have a higher effect of anti-cancer. A professor at the University of Tokyo, Japan, Yamazaki using animal experiments, comparing the immune activity of various fruits such as bananas, grapes, apples, watermelon, pineapple, pear, persimmon, and the results confirmed the effect of the banana is the best it can increase blood cells white, boost immune system function, but also produce abnormal cells attack TNF materials. Experiments Professor Yamazaki also found that the more mature banana epidermisnya with spots more, have higher immune activity. So from now on should eat more ripe bananas!

Bananas are not going to make white blood cells to grow blindly, only in the time will increase significantly. Therefore, experts believe, it has a relatively mild immune activation, the physical condition of a person who would not normally make the immune system become abnormal, but the sick, the elderly, and infirm will be very effective.

Professor Yamazaki showed that the black spots on the epidermis of yellow bananas, can improve the ability of white blood cells 8 times more powerful than the epidermisnya green bananas. Bananas can prevent cancer, colon cancer, kidney cancer. Swedish study found that women who eat 4-6 bananas a week, can reduce the risk of kidney cancer risk.

Included link:

Sabine on February 08, 2015:

The peel of bananas is good for your skin... if your skin is bit inflamed .. also if you mash a banana and use it for a skin mask you can add some other ingredients like olive oil, cacao, honey, strawberry or oats ... etc. as long your not allergic

Stranger2 on January 11, 2015:

One thing most every cancer patient has in common is thick blood. Banana do make the blood thick, reducing circulation and oxegen. Notice how some plants or fruit, berries, trees etc, don't grow in some climates. If they don't grow where you live I would think it best not to eat them. I live in a cold climate, people here take blood thinners to help keep good circulation and stay warm. - food for thought.

healthmunsta (author) on November 05, 2014:

Wow, thank you Random Stranger!

Random Stranger on November 04, 2014:

Some fun facts about bananas.

A strawberry isn't a berry. A banana is.

Bananas, watermelons and apples float in water.

The oil found on the inside of bananas can help sooth bug bites, burns, headaches; same with warts and splinters in a few weeks.

It's radioactive, and can set the alarm off in airports: but not enough to hurt a person.

Can be used to whiten teeth if you rub it against your teeth every night for two minutes.

Bunch of bananas are called a hand; singular ones are called fingers.

The peels are edible if cooked.

75% is made of water.

Hope you enjoy and always eat plenty of this fruit. But then again, maybe you wouldn't want to believe what a Random Stranger said. ;)

codrin on October 11, 2014:

About Professor Senji Uchino

Eric Schwartz on September 15, 2014:

I love bananas no matter what.

Ajarnkenn on August 21, 2014:

I love bananas and I think I would still eat them if they caused cancer;)

Kappaluppa on May 27, 2014:

I'm assuming you have all those misleading articles/blurbs as examples of what is floating around out there. But you don't really say that in your article. It looks like all the referenced information is being validated or propagated by you. Not sure what your stance is.

healthmunsta (author) on April 01, 2014:

Jack, thank you for your contribution. This article now contains a huge update questioning the integrity and existence of this study.

Jack on April 01, 2014:

You "know" it was debunked yet you won't update the article? So people can continue reading this inaccurate information without knowing any better. That's so wrong.

healthmunsta (author) on March 25, 2014:

Hello, everyone. I've recently got 2 skeptical comments saying this article is wrong or junk science. Someone asked me to give a link to the study, and you know what, I couldn't find the link. I wrote this article after being inspired by the very famous Facebook page supporting this topic. Since I can't find the link to that study, what if this whole thing is indeed false?

If one has been diagnosed with cancer, fervently eating a ton of bananas may not cure you from your cancer - you need proper diagnosis and treatment, whether you choose to go with natural medicine or otherwise.

But there is no harm in eating a banana, or any other vitamin-rich fruit, everyday in the hopes of keeping cancer at bay!

In this entire article, I did not say that bananas CURE cancer - I said bananas may help PREVENT cancer. I personally love bananas and have them almost everyday in my smoothies. Will this play a part in preventing cancer for me? Why not!

There are many reasons for cancer (e.g. smoking, exposure to pollution, poor diet, eating unhealthily, lack of exercise, prolonged stress etc) and no one can be sure they're totally safe - but it's entirely okay to, for example, eat a couple of bananas a day to prevent cancer. What's the harm in that?

Of course, if you smoke, or have any other habits that put you at high risk for cancer, no amount of bananas, or any other nutritious food, may help you guarantee a cancer-free life.

Please keep in mind that any comments with outgoing links or abusive language will be deleted. Please don't tell me about how this theory has been "debunked", I think we all know that already. I'm going to keep eating my bananas, and so should you!

Peace out.

thilak raj on March 05, 2014:

Are bananas can be used to produce any harmful chemicals?

Joshua on January 13, 2014:

Do you have a reference or link to the Tokyo study?

Ricardo on January 03, 2014:

If you Google Tumor Necrosis Factor you will find that it does what you are talking about ("necroticizes" tumors, or eats them away) but it does a lot more than that and most of it is really bad. It is a cytokine, you left out the important part thought--it is an "inflammatory" cytokine-as in it causes inflammation. It has been implicated in an unbelievably high amount of diseases, more are being associate with it all the time. Crohn's disease, alzheimers, migraine, endometriosis, the list goes on and on and on. Very few people want to increase their TNF levels. The only way you WOULD want to is if you have cancer, and if you have cancer I would highly encourage you to not try to treat it with bananas.

Serge on December 31, 2013:

What is this article you talk about. Other then disturbing amount of other articles containing the word "banana" on Tokyo University website, there's nothing about this "study". Also "Professor Senji" seems does not exist in their people search either.

ethersteve on December 05, 2013:

A viable healthy alternative (or, complement - for those "stuffies" who refuse to accept they're not always right) to traditional cancer treatment is a diet heavy in antioxidant properties in the most natural environment intended for our composition (good excuse to move to the beach.. think low stress, good sex, no whammy's no whammy's..). This should be carried out methodically and diligently with focus on a high intake of whole foods and large variety of antioxidant supplements - that's right, I said supplements (they sell for a reason). Remove yourself from all negative influences, destructive habits, stressful relationships, and homes high in particulate matter (clutter, old furniture and carpet, pets, dirt - either they go or you should..). No need to overdo it, but get in shape. As your body's condition improves, so will its ability to slow or reverse the cancer. Nay-sayers are too plenty, but I've heard stories ten-fold of those who lost their fight through traditional treatment versus the alternative I'm suggesting. Want more evidence? - I'm a survivor. My suggestion in a nutshell - get lost somewhere nice, get right with God if you have one, find a lover who treats you right and have lots and lots of sex, live and eat healthy, learn how to have fun again, avoid stress at all costs, quit work if you can afford to, and connect with Mother Nature - she will show you the way to life and peace... The object is to enjoy a healthy and positive life and way of living. Do things which fill your heart with gladness and don't hold back or be stingy - you will not see this life again... As you start to feel alive, your body will follow. All the conditions I've mentioned should be in place - each one that is out of place has potential to be a source of illness. Negativity creates cellular disruption - instead, be a force for good and make a difference - the feeling of having truly "earned" your place in life will supercharge you in ways like no other. Be a thrill-seeker and do things which don't freak you out but leave you grinning for days. Solvency in happiness, health, and love is the key to life... There is a Japanese proverb which reads - "If you have money, you have little. If you have love, you have much. But without health, you have nothing..." Prioritize, man.

healthmunsta (author) on November 05, 2013:

@Maher: This has proved true in my personal experience as well, Maher. Eating unripe bananas can cause constipation and hard stools. I actually covered this in my other article entitled, "Do bananas cause constipation?" You may find the link to that in the above article. Thanks.

healthmunsta (author) on November 05, 2013:

@Wintermuet: I don't know what's wrong with you. Nowhere in this article did I say that plants produce cytokines, because it is a known fact that plants cannot produce cytokines. I had to minutely re-read my article once again, only to find that indeed I hadn't made such a statement anywhere, at all. This begs the question, dear reader, did YOU even bother reading my article? The obvious answer is you did not. So before you go around bombing people's articles with your sanctimonious I-know-better-than-everyone attitude, make sure you READ what is written.

Maher on November 04, 2013:

I only noticed that bananas cause constipation if it is green and not yellow/ripe yet. This is just my personal experience

Wintermuet on August 12, 2013:

This is not a true article.

Plants can not produce cytokines.

You should re-read the article by Tokyo University.

The mice produced the TNF, not the bananas.

And it wasn't from being fed bananas. It was from being injected with them, which any first year biology student knows is a hugely different thing than eating something.

healthmunsta (author) on July 09, 2013:

Thanks, everyone!

Tony Sky from London UK on July 02, 2013:

I now know more about bananas than I did when I started reading this, but did you know that bananas as well as Brazil nuts and other foods have very high amounts of radioactive in them which luckily for us are not too harmful I hope.

Amish Writer from Blue Ridge Mountains of the USA on June 30, 2013:

Thanks for this interesting article. I had never heard this info about over-ripe bananas. I like their taste much better than bananas that are just ripe.

peachy from Home Sweet Home on June 30, 2013:

Something that I learnt today never discard over open bananas! Thanks for sharing this article

healthmunsta (author) on June 30, 2013:

Thanks, jabelfiroz!

Firoz from India on June 29, 2013:

Useful article on Bananas for Cancer. Voted up.

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