The anti-cancer effects of cruciferous vegetables like broccoli have long been researched.

Studies show that higher intake of these vegetables is associated with a reduced risk of many cancers.^1,2

Two established cancer-fighting plant compounds found only in cruciferous vegetables are:

Sulforaphane and DIM (3,3’-diindolylmethane)

Research suggests these plant compounds target six different pathways to impede the development of cancer and slow progression of existing cancer.

DIM is readily bioavailable to the body, but it is challenging to obtain sulforaphane from mature broccoli.

This article updates readers on the cancer-fighting properties of sulforaphane and how to deliver it to the small intestine for systemic absorption.

Benefits of Cruciferous Vegetables

The cruciferous vegetables include:

• Broccoli
• Cabbage
• Cauliflower
• Kale
• Brussels sprouts
• Collard greens
• Bok choy
• Arugula
• Watercress
• Radishes.

Vegetables in this family contain a wide range of nutrients, including flavonoids, carotenoids, and minerals.^3,4

Dietary intake of cruciferous vegetables like broccoli and cauliflower has been demonstrated to reduce cancer risk.^5-7

High intake of cruciferous vegetables is also associated with better survival rates in patients already diagnosed with cancer.^8,9

Two unique compounds present in the cruciferous family,sulforaphane and DIM (3,3’-diindolylmethane), modulate pathways involved in cancer development and progression.^10-13

They work in multiple ways to block the development of cancer and to make it difficult for cancer cells to grow and survive.

Promising Sulforaphane Studies

A study published in 2021 evaluated the effect of sulforaphane on human glioblastoma cells.¹⁴ Glioblastoma is an aggressive cancer of the brain or spinal cord that is often incurable.

Sulforaphane stopped the growth of cancer cells in their tracks. It also caused the cancer cells to begin to die off.

Similar results have been seen in other human cancer cell lines, including prostate and breast cancers.^15-21

Sulforaphane has shown promise in animal studies as well.²² In one, rats were given a potent carcinogen. In the group of animals that did not receive sulforaphane, 68% developed tumors.

In rats given sulforaphane, just 39% developed tumors. And in treated rats that did develop tumors, the tumors were smaller and slower growing.

One recent study indicates that sulforaphane may be effective when used alongside certain conventional anti-cancer drugs.

Scientists tested stomach cancer cells, some of which were sensitive to the anti-cancer drug lapatinib and some which were resistant to the drug.²³

Combining lapatinib and sulforaphane stopped the growth and spread of both types of cancer and killed off the cells—even cells previously resistant to the drug.

Improving the Delivery of Sulforaphane

Sulforaphane is an unstable compound that rapidly degrades into non-active substances if it isn’t quickly absorbed or if the vegetable is cooked. Interestingly, it isn’t even present in cruciferous vegetables themselves.

Instead, a precursor called glucoraphanin is stored inside the cells of these plants. In a separate compartment in these cells there is an enzyme called myrosinase.

When these two are combined, the myrosinase converts the glucoraphanin into sulforaphane.

This is what happens when the vegetable is eaten raw. During digestion, sulforaphane is formed. Then, before it degrades, it can be absorbed within the small intestine.^2,5,24

But maximizing these anti-cancer benefits would require the consumption of massive amounts of raw cruciferous vegetables or cruciferous sprouts.

The challenge for scientists was to find a way to deliver glucoraphanin and myrosinase separately to the small intestine.

One group of scientists came up with an ingenious solution that copies nature.

They isolated glucoraphanin and myrosinase from broccoli, then developed a unique delivery system that keeps them separate, just the way plants do.

A dual-layered tablet was given an enteric coating to prevent its ingredients from being released until it reaches the small intestine.

With this delivery system, the compound gluco-raphanin, and the enzyme myrosinase meet and mix in the small intestine. There, they come together to create sulforaphane, just as nature planned.

The results have been striking. Research at the Johns Hopkins University School of Medicine demonstrated that sulforaphane levels from this glucoraphanin-myrosinase mix are three to four times more bioavailable (absorbable) than those created by glucoraphanin supplementation alone.²⁵

Six Anti-Cancer Mechanisms

DIM and sulforaphane act in SIX different ways to help prevent the development of cancer and to slow the spread of existing cancer.

Impeding Cancer Cell Growth

Both compounds can arrest the cancer cell cycle, interfering with the ability of tumor cells to grow.^14-17,19,21

They also block the formation of new blood vessels in tumors, starving them of nutrients and oxygen.^16,26-28

Type 2 transglutaminase is a cancer cell survival protein in several forms of cancer. A study published in 2022 showed that sulforaphane attaches itself to this protein, blocking its activity.²⁹ This further shuts down cancer cells’ ability to survive.

Killing Off Cancer

When normal cells become damaged, they’re supposed to die off through a process known as apoptosis (programmed cell death).

Many cancer cells evolve to shut off apoptosis. DIM and sulforaphane have been found to turn apoptosis back on, initiating cancer cell death.^16,18,20

Reducing Harmful Epigenetic Changes

Cancer can also be caused by epigenetic changes, which happen when genes are turned “on” or “off,” making them active or inactive.

Both sulforaphane and DIM reduce epigenetic changes that contribute to tumor development.^11,30-32

Stimulating Cellular Protection

Nrf2 is a protein that regulates cellular protection. Activating Nrf2 turns on different genes that protect cells against stress and injury.³³

For example, Nrf2 activates enzymes that help eliminate mutagens and other toxins.^34,35

Many of sulforaphane’s benefits stem from its activation of the Nrf2 pathway.³³

Reducing Chronic Inflammation

DIM and sulforaphane both inhibit the action of nuclear factor-kappa B (NF-kB), a regulatory protein that contributes to chronic inflammation.^36-38

This anti-inflammatory effect helps prevent cancer and other chronic health conditions.

Fighting Hormone-Driven Cancer Stimulation

Some prostate and breast cancers are stimulated by forms of estrogen. DIM shifts estrogen balance away from an estrogen form that promotes tumor cell growth and toward a form that inhibits it.^39,40

In women with a history of breast cancer, daily DIM intake increased the proportion of “good” estrogen and reduced the forms linked to faster cancer progression.^39,40

In men, higher estrogen levels are associated with prostate enlargement and cancers. In a cell study, DIM prevented estrogen-induced stimulation of prostate cancer cells.⁴¹

Summary

Many studies show that higher intake of cruciferous vegetables protects against cancer.

These vegetables are a source of two compounds that have demonstrated strong anti-cancer activity: DIM (3,3’-diindolylmethane) and sulforaphane.

Both compounds can stop cancer cell development and growth in their tracks.

Sulforaphane intake has previously been problematic because it is so unstable. A novel two-layer formula enables the nutrient to be bioavailable for absorption into the bloodstream.

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

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