Cancer Tips

$20 Million for Grape Extract?

Muscadines1$20 Million for Grape Extract?

The Takeaway First

The Wake Forest Baptist Medical Center has received $20 million from an anonymous donor to fund research on muscadine grape extract’s effects on breast and prostate cancer. While we don’t know much about this particular grape, we know a lot about grape seed extract and its protective health benefits.

What’s so great about this grape?

Muscadine grapes are native to the southeastern United States and Mexico, and they’re rich in powerful antioxidants. The seeds contain tannins, flavanols, ellagic acid (a polyphenol that has shown significant antiproliferative properties in vitro), and quercetin rhamnoside (one of a family of chemicals used to treat hardened arteries). The skin contains these compounds as well as flavonoids (a type of antioxidant), myricetin (an antioxidant with anti-mutagenic properties), and kaempferol glycosides (kaempferol is known to mitigate oxidative stress).

What Do we Know Right Now?

Wake Forest wouldn’t need $20 million if we knew everything already, but a few studies have given us some hints. We know that muscadine wine extract (as well as cabernet sauvignon wine extract) inhibited the grown of leukemia cells in vitro in one study (Mertens-Talcott et al., 2008). We also know that, in another study, the flavanols and tannins exerted anti-cancer effects in liver cancer cells in vitro (Ti et al., 2006). This is not a lot of information to go on, and it’s relatively old, so it’s safe to say we need to learn more.

My Take on Grape Seed Extracts

Much of my own research has focused grape seed extract. As you might have guessed from the size of Wake Forest’s research gift, we need to learn more about it! Numerous preclinical studies have suggested the anti-cancer and oxidative stress protection of Grape Seed Extract:

Reduces production of the inflammatory chemical, NF kappa b which has shown to be pro-carcinogenic (Dhanalakshmi et al. 2003)

Inhibits tumor growth in mice (Singh et al. 2004)

The pre-clinical data on Grape Seed Extract is compelling, but the human research in 2011is even more attractive. A study found that men who regularly used grape seed extract had a 41% reduction in total prostate cancer risk when compared to other supplements the group was taking (Brasky et al., 2011). Another study around the same time showed that grape seed extract lowered blood pressure .(Feringa et al., 2011).

What Should You Do?

While we wait for more research from Wake Forest and others, strengthen your body now with a eating plant-based whole foods, moving your body and smart supplementation. Grape seed extract is one of several functional phytochemicals and herbs that I recommend to my patients. There are many supplement  companies that have quality Grape Seed Extract: Designs for Health, Douglas labs and Biotics Research (Heart formula) are just a few.

The formula I developed and recommend based on research and  clinical experience is  ImmunoPCTN. This mixture is loaded with much of what your body needs to exercise its natural immunity and be maximally protective against unnatural, aberrant cells.

References

Brasky, T. M., Kristal, A. R., Navarro, S. L., Lampe, J. W., Peters, U., Patterson, R. E., & White, E. (2011). Specialty supplements and prostate cancer risk in the VITamins and Lifestyle (VITAL) cohort. Nutr Cancer, 63(4), 573-582. doi: 10.1080/01635581.2011.553022

Feringa, H. H. H., Laskey, D. A., Dickson, J. E., & Coleman, C. I. (2011). The Effect of Grape Seed Extract on Cardiovascular Risk Markers: A Meta-Analysis of Randomized Controlled Trials. Journal of the American Dietetic Association, 111(8), 1173-1181. doi: http://dx.doi.org/10.1016/j.jada.2011.05.015

Mertens-Talcott, S. U., Percival, S. S., & Talcott, S. T. (2008). Extracts from red muscadine and cabernet sauvignon wines induce cell death in MOLT-4 human leukemia cells. Food Chem, 108(3), 824-832. doi:

Yi, W., Akoh, C. C., Fischer, J., & Krewer, G. (2006). Effects of phenolic compounds in blueberries and muscadine grapes on HepG2 cell viability and apoptosis. Food Research International, 39(5), 628-638. doi: http://dx.doi.org/10.1016/j.foodres.2006.01.001

Dhanalakshmi S, Agarwal R, and Agarwal C: Inhibition of NF-kappaB pathway in grape seed extract-induced apoptotic death of human prostate carcinoma DU145 cells. Int J Oncol 23, 721–727, 2003.

Singh RP, Tyagi AK, Dhanalakshmi S, Agarwal R, and Agarwal C: Grape seed extract inhibits advanced human prostate tumor growth and angiogenesis and upregulates insulin-like growth factor binding protein-3. Int J Cancer 108, 733–740, 2004.

Broccoli Might Be Rewriting Your DNA

DNA

Broccoli Might Be Rewriting Your DNA

The Takeaway First

Broccoli, broccoli sprouts, Brussels sprouts, and cabbage—what do these four greens have in common? They’re all reliable sources of a chemical called sulforaphane, which a brand new study has shown to decrease the risk of certain cancers in surprising ways. Read more below!

Study Details

These authors (Tortorella et al., 2015) looked at everything that has ever been written about sulforaphane, and the evidence suggests that this chemical can repair important genes that, if left undamaged, can lead to cancer.

According to the authors, sulforaphane works in part by targeting a specific family of enzymes called HDACs, which play a role in regulating the expression of genes and the replication of DNA.

Sulforaphane was shown to modulate gene expression by nurturing a class of helper proteins called MicroRNAs. MicroRNAs are tiny pieces of genetic information that float around in the cell and interact with larger pieces of genetic information to affect how genes are expressed. When MicroRNAs are damaged, genes run amok, and tumors are likely to form. (Fun fact: research suggests that MicroRNAs control the expression of about 30% of genes in mammals—they’re really important!)

My Take On This

I had a feeling that something funny was going on in my DNA whenever I ate an extra helping of greens. Just kidding—but I have known for the past 10 years that eating broccoli and other green vegetables can have incredible benefits for your health.

Research continues to show that we need cruciferous vegetables to be healthy. They decrease inflammation (Royston & Tollefsbol, 2015), the risk of cancer, and the risk of dying from cancer. They cut men’s risk of prostate cancer down by 32% (Steinbrecher et al. 2009). Another study showed that eating cruciferous vegetables decreased men’s risk of prostate cancer progression by 59% (Richman et al., 2011). To these impressive facts we can add our new knowledge that one of the key ingredients of these vegetables (sulforaphane) might actually be repairing our damaged DNA as we speak.

But first you actually have to eat the vegetable.

What You Should Do

If you’re a parent, you need to make sure you and your family are getting a healthy dose of green vegetables. (Iceberg lettuce with ranch dressing doesn’t count – the iceberg and ranch dressing are both low level) You want a nice heap of broccoli, cabbage, spinach, kale, broccoli sprouts, and—everyone’s favorite—Brussels sprouts, and you want to get a good amount every day.

Almost half the plate should be green. If you really don’t like broccoli, load up on the other vegetables I just listed. But urge you to learn to like broccoli. C’mon, you are a grown man. If you still can’t find something you like, you can get some of the benefits of these wonderful greens by taking a broccoli-based supplement (or one derived from similar vegetables). But I am one for natural, whole foods, and so I vote veggies!

If you’re feeling creative, or if you like to cook, try this recipe.

 

References

Richman EL, Carroll PR, Chan JM.Vegetable and fruit intake after diagnosis and risk of prostate cancer progression. Int J Cancer. 2011 Aug 5.

Royston, K. J., & Tollefsbol, T. O. (2015). The Epigenetic Impact of Cruciferous Vegetables on Cancer Prevention. Curr Pharmacol Rep, 1(1), 46-51. doi: 10.1007/s40495-014-0003-9

Steinbrecher A, Nimptsch K, Husing A, Rohrmann S, Linseisen J. Dietary glucosinolate intake and risk of prostate cancer in the EPIC-Heidelberg cohort study. Int J Cancer 2009; 125: 2179–86.

Tortorella, S. M., Royce, S. G., Licciardi, P. V., & Karagiannis, T. C. (2015). Dietary Sulforaphane in Cancer Chemoprevention: The Role of Epigenetic Regulation and HDAC Inhibition. Antioxidants & Redox Signaling, 22(16), 1382–1424. doi:10.1089/ars.2014.6097

 

The Supplement Causing Cancer Story is BS…

Concentrated Fiber Capsules OR Fresh Salad

The Supplement Causing Cancer Story is BS…

Takeaway First

Dr. Tim Byers conducted a meta-analysis of two decades worth of research and concluded that a number of supplements actually made a person much more likely to develop certain types of cancer. He presented his research this past Monday, April 20th, 2015 at the annual meeting of the American Association for Cancer Research in Philadelphia. My opinion is this study is not new at all—and complete bullshit! (Oops…I can’t believe I just said that.)

Details of Dr. Byers’ view

Here is the link to the sensational news reports:

University of Colorado Cancer Center 

In an interview with CBS Dr. Byers was quoted:

There’s enough evidence along these lines that we should really consider better regulation of these nutritional supplements,” Byers told CBS News. “I think it’s time to step back and say there’s probably a safety issue.”

Well, is it true? Is there really enough research to show that consuming dietary supplements increase the risk of cancer?

My Take on Dietary Supplements Increasing the Risk of Cancer

This latest news on dietary supplements causing cancer is old, old news. In other words, what Dr. Byers did is rehash studies that began up to 30 years old, most of which we have spoken about ad nauseum like the SELECT study. So, why is Dr. Byers bringing up such old stuff again?

I don’t know. A cynic (and I can be one at times, I admit) would think he is paid by big pharma to bring the supplement industry down to its knees. Or he is simply anti-supplements and anti-natural medicine spokesperson like a few other doctors.

But no. Dr. Byers is a faculty member of the University of Colorado with interest in the role of nutrition and diet in cancer. Why would anyone write a paper that is not only  unoriginal but as old as the Clinton administration?

The answer is simple: money. The more papers you publish in journals, the more publicity you get and the more likely you are to be able to secure grants to continue your investigations. And saying something counter intuitive like “supplements cause cancer” will always get a lot of media attention since we are talking about a nearly $30 billion dietary supplement industry.

You see, researchers are under an astronomical amount of pressure to publish and gain attention for their work, which in turn leads to more research grants – which in turn leads to more security and more appointments. Research scientists are burned out by this pressure to publish as often as possible. It’s publish or perish, as they say in the academic world.

Joeri K. Tijdink, MD, PhD, fellow at Free University Medical Center in Amsterdam, the Netherlands, has been quoted saying:

“If you’re a professor who has a lot of papers that have been published, you feel less burned out and less pressure. This is logical, because you’re more used to how the system works.

By the way, confusion about dietary supplements is a major discussion at the CaPLESS Retreat (prostate cancer health retreat) since some supplements can potentially promote cancer.

Back to Dr. Byers and his Recent Analysis

Through his research, Byers found that people who took high doses of beta-carotene supplements had an increased risk for lung cancer. Again, none of this information is new. The connection between beta-carotene and lung cancer in smokers was published in the mid-1990s. I assume you can find concentrated beta-carotenes in some bottle somewhere, but integrative and naturopathic doctors have been using mixed carotenoids, which might have protective benefits unlike the concentrated form beta-carotene.

Dr. Byers: Men who took vitamin E had an elevated risk for prostate cancer.

Me: OK, are we seriously talking about SELECT again? This goes back to 2008. And besides, if you’ve been reading my blogs for a while you I have highlighted the flaws of SELECT.

But in case you are new to this, allow me to provide an summary:

SELECT was a prospective, randomized, double-blind, placebo-controlled clinical trial of selenium and vitamin E in healthy men who were at elevated risk of prostate cancer by virtue of age or African ancestry. Participants were randomized to receive daily oral doses of either:

  • 200 micrograms selenium (in the form of SelenoMethionine) plus placebo,
  • 400 milligrams dl-alpha-tocopherol vitamin E plus placebo,
  • 200 micrograms selenium plus 400 milligrams dl-alpha-tocopherol,
  • or two placebos.

The study was supposed to last 12 years, but after about 6 years SELECT was stopped following an interim analysis showing that it was unlikely that either selenium or vitamin E had any benefit for prostate cancer.

Further SELECT research showed a 17% increased risk of prostate cancer in those taking 400 of dl-alpha-tocopherol vitamin E and a 91% increased risk of high-grade cancer among men taking SelenoMethionine (selenium). All these men had high selenium status at baseline (Klein et al., 2011).

My take on SELECT

SELECT was a high powered (35,000 subjects), multi-centered ( more heterogeneity) , long-term (12-year) clinical study well funded (between $150 TO $300 million) clinical study.

Unfortunately, SELECT researchers, non of which have a background in nutrition science, by the way,  lost an opportunity to see if using the right form of vitamin E and Selenium would have any benefit in preventing prostate cancer. In other words, we wasted a whole lot of tax payer money on this one.

What do I mean? The vitamin E used in SELECT was a synthetic form – dl-alpha-tocopherol. And the form of selenium used was selenomethionine not High Selenized Yeast (SelenoExcell.

Why is this important? The reason the study SELECT became of interest is because the Alpha Tocopherol Beta Carotene (ATBC) study showed that dl-alpha-tocopherol reduced the risk of prostate cancer.

Oh, yeah. They used 50 units of the unnatural, dl-alpha-tocopherol Vitamin E.

For an unknown reason, researchers used 400 units in SELECT. That’s right – eight times the amount used in the ATBC study – the study that initiated interest. Also, natural vitamin E with high amounts of gamma-tocopherol is protective against prostate cancer. (Jiang et al. 2004). In the year 2000, John’s Hopkins looked at over 10,000 men, showing higher blood levels of alpha-tocopherol and gamma-tocopherol were each associated with a lower risk of developing prostate cancer, but the association with gamma-tocopherol was stronger than that of alpha-tocopherol. (Helzlsouer et al. 2000)

How about Selenium? Interest in selenium’s  protective effects against prostate cancer came from the NPC trial, which showed a reduction in prostate cancer along with other forms of cancer. The problem? The NPC used High Selenized Yeast, SelenoExcell, which is more food-like and less concentrated compared to SELECT, which used 100% Selenomethionine. Selenium Yeast not only consist of selenomethionine but also contains a wide variety of organically bound selenium compounds like selenocysteine and methylselenocysteine, which very likely could have greater anti-carcinogenic activity than selenomethionine alone.

Recently, High Selenized Yeast, SelenoExcell was randomized to placebo  and SeMet (200 mcg/day) administered for 9 months in 69 healthy men. Dr. Richie and his team noticed a reduction in biomarkers of oxidative stress relevant to prostate cancer following supplementation with High Selenized Yeast but not selenomethionine in healthy men. This study suggests that selenium-containing compounds other than selenomethionine may account for the decrease in oxidative stress. (Richie et al. 2014)

If this is not the GIGO effect I don’t know what is.

Other studies Byers reviewed indicated that many other supplements had no apparent impact on cancer riskneither increasing nor decreasing it.

No apparent impact on cancer risk; Really? How come some of the studies I have compiled have shown the opposite?

Take for example a study of a dietary supplement formula consisting of broccoli , turmeric, pomegranate and green tea.

Researchers looked at 199 men, average age 74 years, with localized prostate cancer, 60% managed with primary active surveillance (AS) or 40% with watchful waiting (WW) following previous interventions, were randomised the botanical blend for 6 months.

PSA reflected underlying disease status as the percentage change in PSA was 10-fold lower in the men with and a disease shrinkage was noticed on MRI compared with disease progression no man taking the food supplement had disease progression with a stable PSA. This study would have had more impact if the follow-up would have had a biopsy. But who wants excess biopsies? And who would pay for that? Cost often makes supplement studies prohibitive when a lot of expensive testing is involved. HERE is a link to the study.

In the VITamins and Lifestyle (VITAL) study, which looked at over 35,000 subjects, the use of grapeseed supplements was associated with a 41% reduced risk of total prostate cancer.

Another meta-analysis of observational studies supports an association between higher calcium consumption and reduced breast cancer risk.

One meta-analysis found that higher calcium intake was associated with reduced colorectal cancer risk.

The Physicians’ Health Study, evaluating the impact on men using a regular multivitamin supplement demonstrated a modest 8% reduction in total cancer incidence in men taking a multivitamin. In addition, men with a history of cancer derived the most benefit from MVM supplementation, with a 27% lower incidence of new cancer compared to placebo.

The French randomized clinical trial Supplémentation en Vitamines et Minéraux Antioxydants (SU.VI.MAX) evaluated a supplement containing Vitamin C 120 mg, vitamin E 30 mg, beta-carotene 6 mg, selenium 100 µg, and zinc 20 mg. This supplement was associated with a 31% reduction in overall cancer and a 37% reduction in overall mortality in men but not in women (about 7.5 years).

A meta-analysis of 13 prospective European and North American cohort studies reported a decrease in risk of colon cancer among MVM supplement users compared with nonusers . MVM supplement use for 15 years was associated with a 75% reduction in colon cancer risk in the prospective Nurses’ Health Study (NHS) based on questionnaires completed by 88,756 female nurses in the United States.

But the better question is – why are dietary supplements studied like drugs when they are not drugs?

The scientific method is the approach used by the scientific community to assess if a pharmaceutical drug or a medical procedure has any effect on a particular disease. To control an experiment, you want to eliminate as many confounding factors an isolate the treatment as much as possible.

What do I mean?

If I want to know if drug A, a pill, can cure cancer, then I would set up a study where I recruit, say, 1000 people with cancer (any cancer, to keep it simple), randomly assign 500 to the drug and the other 500 to an indolent pill that looks like pill A but only contains sugar.

I would then follow both groups for as long as possible. The more subjects to study and the longer the study, the more valuable the data and the more clinical relevance it may have. Of course, this gets expensive. That’s why studies like this are rare and should be executed with excellent methodology (the exact opposite of SELECT).

So, when scientists study nutrients in isolation, e.g., dl-alpha-tocopherol (not the natural form with other important components), selenomethinine (without other key forms of selenium), beta-carotene (excluding other carotenoids) – then of course the outcome is rarely good. These are high doses of a single chemical that usually comes in a complex package.

In other words, super concentrated nutrients without the synergism of other key components are similar to pharmaceutical drugs and carry the same risk. But physicians who are nutritionally oriented know that – and have known that for a long time.

And, only integrative, functional, and naturopathic doctors are the experts in the responsible use of nutritional supplements.

So, no, don’t tell your doctor about the supplements you are taking (there is not one nutrition course in Harvard medical school) because she will not know what to do with that information unless she is a nutritionally oriented physician.

Nutrition science and botanical medicine is a discipline in its own right.

So, what should you do…

  • Don’t just take supplements, but eat whole foods (organic as often as possible) from local sources when possible.
  • Exercise for a minimum of 30 minutes a day and then still stay moving afterwards as much as possible.
  • Most good research suggests you can benefit from taking Vitamin D3, so do so. Anything above 2000 units a day should be monitored by an integrative, functional or naturopathic doctor.

Other supplements may very well be helpful but it is always a good idea to seek the help of an expert. I have seen patients who often take way more than what they need.

Whew! This was a long one. :)

Leave comments below as I know this is a hot topic.

References:

Helzlsouer KJ, Huang HY, Alberg AJ,  et al.  Association between alpha-tocopherol, gamma-tocopherol, selenium, and subsequent prostate cancer.  J Natl Cancer Inst. 2000;92(24):2018-2023

Jiang Q, Wong J, Fyrst H, Saba JD, Ames BN. gamma-Tocopherol or combinations of vitamin E forms induce cell death in human prostate cancer cells by interrupting sphingolipid synthesis. Proc Natl Acad Sci U S A. 2004;101(51):17825–30.

Richie JP Jr, et al.Comparative effects of two different forms of selenium on oxidative stress biomarkers in healthy men: a randomized clinical trial. Cancer Prev Res (Phila). 2014 Aug;7(8):796-804.

Thomas R1, Williams M2, Sharma H2, Chaudry A3, Bellamy P4. A double-blind, placebo-controlled randomised trial evaluating the effect of a polyphenol-rich whole food supplement on PSA progression in men with prostate cancer-the UK NCRN Pomi-T study. Prostate Cancer Prostatic Dis. 2014 Jun;17(2):180-6

Your Parents Were Right All Along: Why You Really Should Eat Your Broccoli

Boy-eating-broccoli

Your Parents Were Right All Along: Why You Really Should Eat Your Broccoli

The Takeaway First

In 2010 researchers discovered that sulforaphane, a chemical found in broccoli, reduces the risk of prostate cancer. The latest research adds that this broccoli-derived compound actively kills cancer stem cells. This and other research shows us that the powers of leafy, green vegetables extend further than we think.

The Details

According to a leafy greens review (Royston & Tollefsbol, 2015) published a few months ago in the journal Current Pharmacology Reports, broccoli and other cruciferous vegetables have incredible powers as preventive medicine. Diets high in these vegetables significantly decrease the risk of death from cancer and the risk of developing cancer at all.

This same article explains that eating broccoli is one easy way to create cancer-fighting chemicals in the body. Broccoli turns into glucosinolates, which turn into the sulforaphane. Sulforaphane attacks cancer stem cells and stunts them before they can even begin to metastasize.

On top of all this, eating leafy greens in the same family as broccoli has been found to reduce inflammation (Royston & Tollefsbol, 2015).

The authors of another recent article on sulforaphane (Labsch et al., 2014) recommend a high-sulforaphane diet for cancer-prevention and cancer-suppression.

Related to all this, a brand-new Korean study (Hwang & Lim, 2015) found that broccoli stems and leaves actually have a lot more sulforaphane than the florets (the tiny green buds that bloom from the stalk).

My Take On This

Remember when you were a kid, and the only thing left on your plate after dinner was a dark-green pile of stalky vegetables? If you still avoid these greens, now is the time to stop. Broccoli is one of those powerful, natural preventive medicines that I have come to love in my years of practice. I think of it alongside turmeric, pomegranate, and green tea as a major component to maintaining a cancer-unfriendly body.

And that is why I recommend eating broccoli and all cruciferous vegetables.

These are not exactly groundbreaking studies, but they do confirm the findings of a growing body of research that is uncovering the huge benefits of eating cruciferous vegetables—especially for men like you. In my last post on this topic, I mentioned a study where eating cruciferous vegetables decreased men’s risk of prostate cancer by 32% (Steinbrecher et al. 2009). Even after diagnosis, cruciferous vegetables knocked down another group of men’s risk of prostate cancer progression by 59% (Richman et al., 2011). These are not small numbers!

What You Should Do

OK, so chances are your parents did not know that broccoli had such an ability to decrease your risk of cancer, let alone prostate cancer, and I’m 99.9% sure they didn’t know that broccoli directly targets cancer stem cells by flooding your body with sulforaphane—but you have to admit: they were right.

I know you know what to do, but I’ll say it anyway: eat broccoli. Don’t just eat the thinner stalks and the florets; eat the big, chunky stems and the leaves, too. My juicer friends sometimes tell me they add kale and broccoli leaves to their morning smoothies. Make sure to steam them well, however. Raw broccoli contains chemicals called goitrogens which can cause thyroid problems down the road. Also, broccoli is tough to digest when raw. Skip the raw broccoli from the veggie platter at the next party. The carrots are fine to eat raw—and easy on the creamy dip! (I digress.) Personally, I prefer colorful fruits in my smoothies (pomegranate is powerful and delicious) mixed with leafy greens. I do not like broccoli in my smoothie, but you might. Supplements made out of broccoli extract also seem to help – I recommend them often. For your health and your gustatory pleasure (trust me, it’s a word): try one of my favorite recipes:

Creamy Cruciferous Soup by Marti Wolfson – Culinary Nutrition Educator
  • This luscious emerald soup is surprisingly rich sans the cream which many pureed soups contain. I especially love to make this soup transitioning from winter to spring. The liver reaps great benefit from the broccoli, cabbage and as well as aliums such as onions and garlic. You can swap your favorite greens like spinach, kale or dandelion greens or herbs like parsley, thyme, and rosemary.

    Serves 8

    Ingredients:

    • 1 T. olive oil
    • 1 medium onion, diced
    • 1 tsp. ginger, minced
    • 2 cloves garlic, minced
    • 4 celery stalks, chopped
    • 3 cups chopped broccoli, florets and stems
    • 1 head, fennel, chopped
    • 2 cups chopped savoy or napa cabbage
    • 6 cups water or stock
    • 1 tsp. sea salt
    • 1/8 tsp. ground black pepper

     

    Procedure:

    Heat the oil in a large pot on medium high heat. Add the onion and cook until the onions are translucent. Next, add the ginger, garlic, celery, broccoli, fennel, cabbage and a generous pinch of sea salt and continue to cook another 2 minutes. Add the water or stock, remaining sea salt and pepper.

    Bring to a boil, cover and reduce the heat, simmering for 20 minutes. Place the soup in a blender and blend until smooth and creamy. Taste for salt.

     

References

Hwang, J.-H., & Lim, S.-B. (2015). Antioxidant and Anticancer Activities of Broccoli By-Products from Different Cultivars and Maturity Stages at Harvest. Preventive Nutrition and Food Science, 20(1), 8–14. doi:10.3746/pnf.2015.20.1.8

Labsch, S., Liu, L. I., Bauer, N., Zhang, Y., Aleksandrowicz, E. W. A., Gladkich, J., . . . Herr, I. (2014). Sulforaphane and TRAIL induce a synergistic elimination of advanced prostate cancer stem-like cells. International Journal of Oncology, 44(5), 1470-1480. doi: 10.3892/ijo.2014.2335

Richman EL, Carroll PR, Chan JM.Vegetable and fruit intake after diagnosis and risk of prostate cancer progression. Int J Cancer. 2011 Aug 5.

Royston, K. J., & Tollefsbol, T. O. (2015). The Epigenetic Impact of Cruciferous Vegetables on Cancer Prevention. Curr Pharmacol Rep, 1(1), 46-51. doi: 10.1007/s40495-014-0003-9

Steinbrecher A, Nimptsch K, Husing A, Rohrmann S, Linseisen J. Dietary glucosinolate intake and risk of prostate cancer in the EPIC-Heidelberg cohort study. Int J Cancer 2009; 125: 2179–86.