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Cruciferous vegetables containing sulforaphane with cancer-fighting properties

Cancer Risk Reduced with Cruciferous Vegetables

Research shows that compounds in cruciferous vegetables confer protection against many forms of cancer.

Scientifically reviewed by: Dr. Crystal M. Gossard, DCN, CNS, LDN, on July 2020. Written By Kirk Stokel.

Roughly 1.8 million Americans are diagnosed with cancer each year.

More than 600,000 people in the United States die from it annually.1,2

It doesn’t have to be this way.

Many cancers are preventable.

Improving diet, increasing exercise, and changing unhealthy behaviors can significantly reduce risk.3

Studies show that higher intake of cruciferous vegetables is associated with a reduced risk for cancers.4,5

Ongoing research points to anti-cancer effects of compounds found in broccoli and other cruciferous vegetables.

One clinical trial showed that a specific cruciferous vegetable nutrient triggered a complete resolution of pre-cancerous cervical lesions in 100% of women, removing the risk that the lesions could develop into cancer.6

Until recently, it was difficult to deliver these cruciferous nutrients into the bloodstream at high enough levels to be effective.

Scientists have found a way to maximize the activity of cruciferous compounds so that they can reach tissues throughout the body.

Cruciferous Vegetable Compounds

Cruciferous vegetables that contain sulforaphane

Cruciferous vegetables are a group of edible plants that include broccoli, kale, green and red cabbage, cauliflower, and Brussels sprouts.

They are loaded with nutrients shown to help prevent a wide variety of common disorders.

In particular, cruciferous vegetables have demonstrated the ability to protect cells from several processes that result in malignant transformations.4,5

Two cruciferous nutrients are especially well validated for their cancer-fighting properties:

  1. Sulforaphane
  2. DIM (3, 3’-diindolylmethane).6-8

Findings from Johns Hopkins

In a seminal 1994 study from Johns Hopkins, rats were split into two groups. One was treated with sulforaphane, and one was not.9

All the animals were then exposed to a powerful cancer-inducing chemical.

The sulforaphane-treated rats developed 39% fewer tumors than the untreated group. And the tumors that did develop progressed at a slower rate.

Other studies have produced similar findings, showing that sulforaphane kills cancer stem cells, slows the growth of tumors, and promotes the death of cancer cells.10-12

In lab and animal studies, sulforaphane has been associated with diminished growth of cancer cells and a reduced risk of many types of cancer including:

The other active compound in broccoli, DIM, also shows the ability to slow or even stop cancer cells from growing.

In one remarkable study, women with cervical intraepithelial neoplasia, a cervical cancer precursor, were treated with DIM.

After three to six months, 100% of women receiving 200 mg of DIM daily had their neoplasia completely resolved, compared to 61% of women in a placebo group.6

What’s most striking about these cruciferous compounds is that they have shown these effects on cancer in virtually every tissue studied.

How Plants Create Sulforaphane

You can’t get these benefits by simply popping a pill containing sulforaphane.

The reason is that while DIM is stable, sulforaphane is not. It degrades rapidly into inactive substances if it isn’t quickly absorbed.26

Nature has found a way around this problem.

Sulforaphane isn’t contained in cruciferous vegetables. Instead, cruciferous plants store a sulforaphane precursor called glucoraphanin in their cells.

In a separate cellular compartment, plants store an enzyme called myrosinase, that converts glucoraphanin into sulforaphane.

Only when the vegetables have been eaten and partially digested do the glucoraphanin and myrosinase mix, to form sulforaphane, the cancer-fighting compound.

Sulforaphane can then be absorbed through the small intestine before it degrades.

What you need to know

The Cancer-Fighting Power of Cruciferous Veggies

  • Cruciferous vegetables include broccoli, cabbage, cauliflower, Brussels sprouts, and kale.
  • Two cruciferous nutrients are especially well validated for their cancer-fighting properties: sulforaphane and 3,3’-diindolylmethane (DIM).
  • Unlike DIM, sulforaphane is unstable. It degrades rapidly if it’s not absorbed.
  • Scientists have found a way to package a sulforaphane precursor with an enzyme that converts it into sulforaphane in the small intestine, where it’s absorbed into the bloodstream right away.
  • Together, sulforaphane and DIM can prevent changes that lead to cancer, stop tumors from developing and spreading, and even cause cancer cells to die off.

Science Imitates Nature

Formation pathway of anti-cancer compounds in cruciferous vegetables

The trick for researchers was to find a similar way to deliver sulforaphane to the small intestine before it breaks down.

One group of scientists came up with an ingenious solution: imitate nature.

They developed a delivery system that keeps stable glucoraphanin and active myrosinase in separate compartments, just the way plants do.

Taken orally, these two components meet and mix only in the small intestine.

That means higher levels of cancer-fighting sulforaphane can be achieved.

The results are striking. Scientists at Johns Hopkins found that sulforaphane levels from this gluco-raphanin-myrosinase mix are three to four times more bioavailable (absorbable) than those created by glucoraphanin alone.27

How Sulforaphane and DIM Work

Sulforaphane and DIM have shown the ability to reduce cancer risk and malignant changes in four important ways:

  • Stop deleterious epigenetic gene expression changes from occurring,
  • Reduce or minimize cancer-promoting chronic inflammation,
  • Fight estrogen-driven stimuli that encourage cancer cell replication and spread and
  • Impede pre-cancerous cells from developing into tumors.

Stopping Epigenetic Changes

Cancer can be caused by epigenetic changes, the ability to “turn genes on and off.”

Epigenetic changes can be described as changing gene expression via one’s behavior or inadvertent exposure to outside toxins like air pollution.

By way of example, smoking cigarettes causes deleterious epigenetic changes that make the smoker more vulnerable to certain cancers.

Fish oil and vitamin D, on the other hand, have been shown to induce beneficial epigenetic changes.

These changes don’t alter the DNA, but they change expression patterns of genes.

Research has shown that sulforaphane and DIM can reverse some of these cancer-associated changes.16

One example of this is that sulforaphane reverses alterations in histone proteins involved in the regulation of genes, an epigenetic change that can help prevent cancer formation.28,29 This mechanism is so important, it’s a target of many new cancer drugs under development.30-32

Suppressing Inflammation

Chronic inflammation contributes to practically every age-related disease—including cancer.

Our bodies have a “master switch” that regulates the signaling molecules that drive inflammation. It’s called nuclear factor-kappa B (NF-kB).

Studies show that sulforaphane blocks NF-kB, reducing inflammation throughout the body. Along the way, sulforaphane kills cancer stem cells that can trigger tumor recurrence.11,33

Fighting Estrogen-Driven Stimuli

Certain estrogens stimulate proliferation of some existing breast and prostate cancers.34-36

Sulforaphane combats the potential DNA-damaging effects of estrogen, preventing the early DNA damage that leads to cancers.37-39

DIM helps shift the balance between two different forms of estrogen metabolites, away from one that promotes cancer and toward one that inhibits it.40

In women who have had breast cancer, human studies show that daily DIM shifts estrogen metabolites toward a preponderance of the healthier form.40,41

In men, higher estrogen levels are associated with prostate enlargement and cancers. Studies show DIM can prevent estrogen-induced stimulation of prostate cancer cells.42,43

Stop Developing Tumors in their Tracks

Sulforaphane has demonstrated the ability to suppress signals and enzymes that spur growth of tumors, and to reduce formation of blood vessels that feed them.44-49

DIM has also been shown to reduce new blood vessel formation in tumors and to inhibit the spread of cancer.50

And both compounds spur cancer cells to die off, while leaving normal, healthy cells unharmed.51,52

These actions prevent pre-cancerous cells from developing into cancer and slow the growth of existing cancer.

Summary

Head of cabbage and stick of rosemary

Cruciferous vegetables like broccoli have proven capable of slowing and even reversing the development of many types of cancer.

Research shows that many of the anti-cancer effects are due to two compounds derived from these vegetables: sulforaphane and DIM.

While DIM is stable and easily absorbed when taken orally, sulforaphane is rapidly converted to inactive compounds.

To solve this problem, scientists developed a delivery system (glucoraphanin plus myrosinase) that maximizes the amount of sulforaphane available for absorption into the bloodstream.

By separating these precursor plant compounds, much more sulforaphane becomes bioavailable in the small intestine. There, it can be rapidly absorbed, delivering higher blood levels of this beneficial (sulforaphane) compound.

If you have any questions on the scientific content of this article, please call a Life Extension® Wellness Specialist at 1-866-864-3027.

References

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