I always wonder what brings people to this little, humble corner of the internet where I write up some of the alternative treatments, diets, and supplements I read about (and even try). Who are you? What are you doing here? Do you find my articles helpful? Understandable? Do you cross-reference them to make sure I’m honest? Well, it’s neither here nor there and just a stream-of-consciousness thought. Today I’m finally writing up my studies on iodine and the prostate. A friend of my husband has prostate cancer and needs to have surgery. He wanted me to get some articles regarding iodine and the prostate to give to his friend, so I did. I thought I’d continue on in my iodine write-up here for this blog.
If you search for iodine and prostate on the internet, you’ll come across some pretty dramatic, anecdotal claims–got some coffee up my nose a time or two (or even three) while reading. What’s real? Can iodine make a man shoot across the room? Well, there’s not enough iodine and prostate information out there to know much, but the scant research teases us with at least iodine’s efficacy in preventing prostate cancer and reducing benign prostatic hypertrophy.
Real Life Evidence That Iodine May Impact Prostate Cancer
You’ll read this everywhere on the internet about iodine: Japanese men have one of the lowest prostate cancer rates in the world and some of the highest iodine intakes. They consume large amounts of salt-water fish and seaweed, both iodine-rich food sources. The Japanese age adjusted prostate cancer incidence rate is 12.6 men per 100,000 men; in the United States it is 124.8 men per 100,000 men. That’s a significant difference, eh, by any statistical, analytical contortion. When Japanese men move to the United States and adapt a non-traditional diet, maybe some Totino’s pizza, microwave popcorn, or honey mustard dressing in a plastic bottle, their incidence of prostate cancer rises. Now, this is all interesting and observational. Is it the iodine? The omega-3 in the fish? The micronutrients in the kelp? The air in McDonald’s? (1)
Well, wouldn’t it be nice to know? It would. In 1997, The British Journal of Cancer published a dietary study trying to label fat intake as a prostate nemesis, and they also looked at other nutrients as a side show. Fat intake was actually not found to correlate (so throw up the yellow flag on fat fears), but when looking at other nutrients, they found that the higher the iodine intake, the lower the risk of prostate cancer. Statistical contortion methods almost significantly indicated that high iodine intake was associated with less prostate cancer—but no cookie. (Please don’t eat cookies. Well, not many anyhow.) High iodine intake was defined as greater than 156 micrograms per day, which is higher than the recommended intake in the United States and well below the intake in the average Japanese man. I wonder if anything significant would have turned up had they stratified out even higher intakes of iodine among the study population. That’s all I can do is wonder. And cook fish for my hubby. (2)
It’s Not All About The Thyroid
So, maybe iodine might, possibly, could help prevent prostate cancer. How? What could it do? Well, we used to think that iodine was only needed by the thyroid gland– but oh, how we are learning that, ahem, we were wrong. (Why isn’t anyone blushing? Stammering?) In fact, the prostate and many other organs and tissues will actively pull in and accumulate iodine as long as there is enough iodine present in the body. However, the thyroid gets preferential uptake of iodine. The doses of iodine recommended in the United States barely make the cutoff for thyroid needs, forget the breasts, brain, salivary glands, ovaries, testicles, prostate, and stomach! (3)
Iodine In The Prostate
Iodine, fascinatingly, is being found to have anti-proliferative, antioxidant, anti-microbial, and anti-inflammatory effects. Increased levels of iodine regulate mitosis, reduce free-radical induced DNA damage, and markedly reduce tissue fibrosis. All these functions add up to protection. Iodine seems pretty protective. Studies on mice and in test tube cells have shown that iodine can cause prostate cancer cells to self-destruct (known medically as apoptosis) and to differentiate (a good thing). Cancerous cells begin to lose all resemblance to the tissue type they are supposed to belong to, and iodine helps prostate cancer cells go back to resembling normal prostate cells (known medically as differentiation). This sounds promising, but it just isn’t concrete enough evidence to say that iodine benefits prostate cancer. (1,3)
Although we use the general term iodine, the body actually uses iodine (I2), iodate (I-), and 6-iodolactone. Using human cell lines in mice, research has elucidated that both normal prostate cells and cancerous prostate cells are affected by all three forms of iodine. Iodine inhibited cell proliferation and promoted apoptosis (programmed cell death). Interestingly, the 6-iodolactone iodine form is a powerful form that is only formed in the body when there is enough iodine (and it seems to be more if it’s the I2 form) present at certain levels and certain lengths of time. So, if you’re barely scraping by to feed the thyroid, you may not be getting the amount, concentration, and duration necessary to make 6 iodolactone! 6-iodolactone cannot be detected in human tissue when iodine deficiency is present. (4)
What About Benign Prostatic Hypertrophy (BPH)?
My searches for information about benign prostatic hypertrophy and iodine brought up even less than what I found for prostate cancer and iodine. What little I found seemed very seductive, but when I tried to track down the primary sources myself, it proved a little sticky. The paper titled “The Extrathyronine Actions of Iodine as Antioxidant, Apoptotic, and Differentiation Factor in Various Tissues” ran in the journal Prostate in 2013. The following is an excerpt from this article:
“Similarly, I2 treatment (3–6 mg/day) of patients with benign breast disease is accompanied by a significant bilateral reduction in breast size and remission of disease symptoms, effects not observed when I− or protein-bound I− is administered. Moreover, similar benefits have been found in benign prostatic hyperplasia, in animal models with 0.05% I2 supplementation, and in human patients with early benign prostatic hyperplasia (stages I and II) where an 8-month Lugol (5 mg/day) supplement was accompanied by diminished symptoms and prostate-specific antigen values, and an increased urine flow rate.”
This excerpt just sounds wonderful, but I was not able to access the sources. One is a textbook where you can read just a garbled bit on Google and the other was presented at a scientific convention.
On a personal note, we do use a little bit of iodine supplementation in our family because we don’t have reliable iodine sources in our diet. We try to eat seafood abundantly and incorporate seaweed, but the main cook in our family (me) sometimes gets a little tied up in little arms (kids) and doesn’t quite cook the way she means to. Upon questioning, it was reported to me that nocturnal urination symptoms in the laborer of our family diminished with iodine. Anecdotal? Yes. Absolutely.
Yes. Iodine does seem to play an important role in the prostate, and 150 micrograms does not seem like enough to get the protective effects. You’ll be hard-pressed to find a conventional medical doctor who will encourage you to take more iodine. In medical school and residency, we were taught that iodine can trigger hypothyroidism or hyperthyroidism. Yes, it can rarely do that, especially if other nutrients are missing as iodine is added in. But I really can’t help but think that we need some more iodine than we’re getting (or perhaps we simply need to get less of what interferes with iodine’s function in our bodies—which is exceptionally difficult to do in our modern world). IF iodine would help a subset of population avoid prostatectomy, chemotherapy, and radiation, boy, it seems like a simple thing to observe for hypothyroidism and hyperthyroidism compared to impotence.
My homeschooled iodine education must concur with the minority of healthcare professionals out there pushing for higher doses of iodine. BUT due to the high incidence of subclinical selenium; zinc; B vitamin deficiencies; and the fact that some forms of iodine are better than others, it must be done cautiously and under the scrutiny of a trained eye. Rarely, a patient may convert to florid hyperthyroidism or hypothyroidism.
This blog site and this post are not to be used for medical advice or treatment. That would be silly. Have a great day and a wonderful life. I’ll leave you with a quote from one of the sources:
“We propose that the International Council for the Control of Iodine Deficient Disorders recommend that iodine intake be increased to at least 3 mg/day of I2 in specific pathologies to obtain the potential extrathyroidal benefits described in the present review.” (3)
- Cann SA, Qiu Z, and van Netten C. A Prospective Study of Iodine Status, Thyroid Function, and Prostate Cancer Risk: Follow-up of the First National Health and Nutrition Examination Survey. Nutrition and Cancer. 2007. 58(1): 28-34. Full text if it is still up.
- TJA Key, PB Silcocks, GK Davey, PN Appleby and DT Bishop. A case-control study of diet and prostate cancer. British Journal of Cancer. 1997. 76(5): 678-687. Full text.
- Aceves C, Anguiano B, Delgado G. The Extrathyronine Actions of Iodine as Antioxidant, Apoptotic, and Differentiation Factor in Various Tissues. Thyroid. 2013 Aug. 23(8): 938-946. Full text.
- Aranda N, Sosa S, Delgado G, Aceves C, Anguiano B. Uptake and antitumoral effects of iodine and 6-iodolactone in differentiated and undifferentiated human prostate cancer cell lines. Prostate. 2013;73:31–41. (I got this from ReadCube.) Abstract.