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The Benefits of Selenium for Preventing Cancer

Angela has lived with many inflammatory illnesses. Through the changes in her diet and the use of supplements, her life has turned around.

One brazil nut gives you enough selenium for one daily serving.

One brazil nut gives you enough selenium for one daily serving.

Selenium's original purpose was to treat dandruff. Still, through further research, selenium has proven beneficial in blocking specific chemical reactions that cause free radicals in the body, primarily when used with vitamins C and E. Free radicals cause cancer cells to develop by changing the DNA. Many scientific studies have researched the effectiveness of selenium on cancerous tumors over the years.

The average adult requires at least 55 micrograms (mcg) per day to have minimal anti-cancer effects. Pregnant women should get 60 mcg a day, while a woman who is breastfeeding should get 70 mcg a day. These are minimum amounts. For optimum benefits, the body needs 200 mcg.

Different studies show different amounts that can cause toxicity due to too much selenium; therefore, it is advised not to exceed 400 mcg. If you exceed that amount, the most common symptoms are an upset stomach, hair loss, or white blotches on your nails.


Selenium and Cancer Prevention

The book Earl Mindell's Supplement Bible points out that the Japanese diet has four times the amount of selenium. He hypothesizes that fewer Japanese men get prostate cancer than American men, which is further proven in China when comparing areas where the soil is rich in selenium and where the ground is not. Food gets its selenium from the soil it grows in. Those who live in areas where the soil is rich in this mineral have a much lower frequency of cancer than those who live where it is not as available.

Due to scientists' suspicion that this element can prevent cancer, many have studied the effects of selenium. In test-tube studies, cells have a very rapid reaction to selenium. Selenium repairs the cell and helps it have a healthy life cycle, protecting it from deforming, which eventually causes cancer. Selenium acts very quickly in the body, as well.

Another study from Cornell University and the University of Arizona showed that after five years, those who took 200 mcg a day were:

  • 63% less likely to develop prostate tumors
  • 58% less likely to develop colorectal cancers
  • 46% less likely to develop lung malignancies
  • 39% less likely to die from cancer

A study in 1996 done by Dr. Larry Clark of the University of Arizona showed similar effects when studying 1,300 older people. Half received a placebo, and the other half received 200 mcg. After seven years, those who took the placebo were 42 percent more apt to have cancer than those who took the mineral. Of those who had cancer, the ones that did take selenium were half as likely to die.

One study done in 2007 on organ transplant patients did not show this significant effect on cancer. People who undergo organ transplants are more apt to get skin cancer linked to the human papillomavirus. Over the two years that the study took place, there showed no difference in those who ended up with cancer and those who did not.


A Vitamin for Cancer Treatment and Other Things

Although your body needs at least 60 mcg, 200 mcg has a more significant effect on the body. Since it is hard to control how much selenium is in your diet, many doctors recommend supplementation. Despite many studies about selenium supplementation and cancer prevention, the evidence is not yet thorough enough to be proven.

Even if it does not entirely stop cancer, selenium:

  • It improves your immune system and ultimately decreases the chance of cold sores and shingles
  • Benefits to those who have HIV
  • Improves fertility in men
  • It helps stabilize diabetic insulin levels
  • Improves your mood
  • Decreases risk of clotting and protects against heart disease and stroke
  • Slows aging progression
  • Assists in healthy thyroid functioning
  • Allows for more youthful skin and hair
  • Promotes eye health and possibly prevents cataracts and macular degeneration
  • Increases good cholesterol (HDL) and decreases bad cholesterol (LDL)



Selenium and Chemotherapy

In combination with vitamin C and E, Selenium makes chemotherapy safer and more effective because it is an excellent antioxidant, preventing the free radicals that occur as a result of the chemotherapy. By taking selenium, patients on chemotherapy have shown to have fewer side effects than those who do not take the supplement. Part of this is because chemotherapy reduces the amount of selenium in a person's body. Therefore, by taking the supplement, you replace what the chemotherapy has removed from your body. Another great benefit is that selenium binds to platinum and other heavy metals, which causes chemotherapy to be less toxic.

Not only does selenium help reverse the side effects of chemotherapy, but it also enhances the effectiveness of chemo, radiation, and hyperthermia, which Patrick Quillin points out in his book Beating Cancer with Nutrition.

They studied 62 women with ovarian cancer averaging 50 years old, and the side effects of chemotherapy in combination with the effect selenium had. They had a combination of several minerals such as beta-carotene, vitamin C and E, riboflavin, and niacin. One group had this combination with selenium, and one group had them without selenium. For three months, they took these once a day. Within the study, they tracked the severity of the person's side effects of chemo, markers of free radical activity within the body, and red and white blood cell counts.

The results showed the selenium group:

  • Had higher amounts of glutathione peroxidase in red blood cells, which indicates improved antioxidant activity
  • Had more neutrophils in white blood cells, which is responsible for fighting off infections
  • Experienced less nausea, vomiting, abdominal pain, gas, mouth sores, weakness, hair loss, and malaise
  • Had better appetites
  • Had the same amount of diarrhea as other groups

Not only does it help those with chemotherapy, but it also slows the progression of cancer and assists in the prevention of it. There are so many great benefits to taking 200 mcg of selenium that it should be part of our daily routine. If you have cancer, you should begin discussing with your doctor the benefits of taking selenium, especially if you will have chemotherapy.


This article is for informational purposes only. Please consult a licensed healthcare professional for the best and safest treatment for your specific situation.


  • Selenium and Vitamin E Cancer Prevention Trial (SELECT): Questions and Answers. (n.d.). Retrieved January 27, 2018, from
  • Test ID: SES Selenium, Serum. (n.d.). Retrieved January 27, 2018, from and Interpretive/9765
  • The mineral selenium proves itself as powerful anti-cancer medicine. (n.d.). Retrieved January 27, 2018, from

This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.

© 2012 Angela Michelle Schultz


Mary Norton from Ontario, Canada on November 03, 2014:

We usually have nuts to snack on but I just haven't really gone for Brazil nuts. Will have to look for some after reading this.

Elizabeth Parker from Las Vegas, NV on August 15, 2013:

Wow- very interesting information! I'm going to have to look into taking this!

Angela Michelle Schultz (author) from United States on October 14, 2012:

Thank you very much for your very interesting comment. I can see your comparison to cancer to fungus. I never thought of it that way.

Man from Modesto from Kiev, Ukraine (formerly Modesto, California) on October 13, 2012:

Okay, I never knew Brazil nuts looked like an alien eating orifice. Won't be eating those for a long time!

Seriously, there are many foods and eating habits that can conquer cancer. Do some research on Tullio Simoncini, the Italian doctor. He proved what the Holy Spirit showed me in a dream more than 15 years ago: cancer is fungus. The body covers it with a protective coating of specialized skin. The scraping sent to the lab looks like "abnormal" skin because it is- but not really abnormal. It is specialized to seal off the colony of fungus inside it.

Think about it: can a type of human cell break off, migrate, land somewhere else, and then grow? If it could, why do we not find heart tissue growing on bone, or bone tissue growing striated muscle? Fungus does exactly that: it migrates, lands in new locations, and grows there. Surgeons always want to remove the entire lump and not be too conservative. They fear breaking the cancerous tumor and spreading the cancer to other locations when those cells spread. What? If it could spread, it would have already- unless something (specialized human tissue) was containing it.

Sodium bicarbonate (baking soda) raises the body's pH. Fungus cannot live in high pH, and dies.

The pit of the peach (crack open the pit and eat the thin 'almond') has a nut inside which also kills cancerous cells.

Angela Michelle Schultz (author) from United States on October 13, 2012:

Yes, I as well, have a new appreciation for Brazil Nuts. :)

Brenda Barnes from America-Broken But Still Beautiful on October 13, 2012:

Thanks for the great information. I truly believe diet can prevent or cure any ailment. My family loves Brazil nuts and now I know more of their benefits. I will soak them now and we shall have two a day. You did a great job researching this Hub. Congratulations on a very professional presentation.

Susan Zutautas from Ontario, Canada on October 13, 2012:

Normally I only buy Brazil nuts at Christmastime, but after reading your hub I'll make Brazil nuts part of my everyday diet. I never realized how good they are for you.

Dianna Mendez on October 12, 2012:

This is wonderful news on selenium. I must say that for such a natural food remedy for cancer, it does much for the body. Thanks for the information. Voted up and shared.

Angela Michelle Schultz (author) from United States on October 12, 2012:

Thank you everyone for your wonderfully sweet comments. :)

Ms. Immortal from NJ on October 12, 2012:

Yes, I agree if the brazil nut is soaked, one may be enough. Through my research I have found that we are not getting all the minerals we think we are getting when eating unsoaked nuts because of the phytic acid; which binds the minerals. Phytic acid makes it harder for our bodies to readily absorb the selenium in brazil nuts unless soaked in water for several hours.

There is no way I could get my family to soak nuts, the most I could hope for is that they eat them.

Debbie Pinkston from Pereira, Colombia and NW Arkansas on October 12, 2012:

This is extremely interesting and I wonder if physicians, especially oncologists, are paying attention to the great benefits of this mineral. I plan to pass this on to several friends who have cancer.

Thank you!

Kate McBride from Donegal Ireland on October 12, 2012:

This is such a well-researched hub on the health properties of selenium which are far more than I realized before reading it. Voted up,useful and shared on facebook. Thanks!

Angela Michelle Schultz (author) from United States on October 12, 2012:

Actually one brazil nut a day will be enough selenium for an entire day. Five could actually cause toxicity. :)

Ms. Immortal from NJ on October 12, 2012:

Great hub and very accurate. I had read a while back that Ohio has the lowest selenium count in their soil.

When visiting my family in Ohio, I gave the each a bag of brazil nuts and told them to eat 5 a day. (they think I'm crazy) I don't care, as long as they listen to me, I am happy.