Life Extension Magazine®
Man in garden holding broccoli with the compound sulforaphane

How to Obtain Broccoli's Beneficial Compounds

Sulforaphane, a compound found in broccoli, is poorly absorbed, and depleted by cooking. A dual-layered delivery system mimics nature to deliver more sulforaphane into the bloodstream.

By Michael Downey.

Up to 90% of all cancers are caused by environmental and lifestyle factors.1,2

Research shows that a higher intake of broccoli and other cruciferous vegetables is associated with a reduced risk of cancer.3,4

But until recently, optimizing intake of a beneficial cruciferous vegetable compound called sulforaphane has been challenging.

A novel delivery system keeps the sulforaphane precursor (glucoraphanin) apart from the myrosinase enzyme until they reach the small intestine.

Once in the small intestine, myrosinase converts glucoraphanin into sulforaphane for absorption into the bloodstream.

Cruciferous Nutrients Inhibit Cancer

Cruciferous vegetables include broccoli, kale, cabbage, cauliflower, watercress, and Brussels sprouts.

Studies going back decades have shown that large dietary intake of these foods is associated with a reduced risk of developing different forms of cancer, including many of the most common types, like lung and colorectal cancer.4-6

That’s because cruciferous vegetables are loaded with compounds that shield cells from processes that can transform them into malignant tumors.3,4

Two of the most protective compounds are:7-9

  • Sulforaphane and
  • 3,3’-diindolylmethane (DIM).

DIM is a stable compound that is readily absorbed from the digestive system.

Sulforaphane, however, is unstable. It rapidly degrades into non-active substances if it isn’t quickly absorbed or if the vegetable is cooked.

Nature has found a way around this problem.

How Plants Produce Sulforaphane

Cruciferous vegetables that produce sulforaphane

Sulforaphane is a cancer-fighting compound we get from cruciferous vegetables. And yet it isn’t present in them.

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

When mixed together, the myrosinase converts the glucoraphanin into sulforaphane.

This is what happens when the vegetable is eaten raw. During digestion, sulforaphane is formed. It can then be absorbed within the small intestine before it degrades.4,5,9

But maximizing these anti-cancer benefits would require the consumption of massive amounts of raw broccoli.

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

Mimicking Nature

Scientist examining isolated glucoraphanin and myrosinase

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

They isolated glucoraphanin and myrosinase from broccoli, then developed a 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 unique delivery system, the compound glucoraphanin 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.10

Sulforaphane Reduces Cancer Risk

Maximizing production of sulforaphane can have a huge impact on fighting cancer.

Lab and animal studies show sulforaphane:11-13

  • Kills cancer stem cells,
  • Slows the growth of tumors, and
  • Promotes the death of cancer cells.

In one study, rats were divided into two groups. One was given sulforaphane and the other was not. Both groups were then given a strong carcinogen.

The animals that had been given sulforaphane developed fewer tumors compared to controls. The tumors that did develop were smaller and grew more slowly.14

A large body of preclinical research has revealed great promise for sulforaphane as regards reducing the risk of many cancers, including those of the:

  • Breast,11-13
  • Bladder,15
  • Lung,16
  • Prostate,17
  • Cervix,18-20
  • Blood (leukemia),21-23
  • Mouth,24 and
  • Brain.25,26

The Anti-Cancer Effects of DIM

The benefits of the cruciferous nutrient DIM have been evaluated in a study of women with a history of breast cancer.27

In this study, women were randomized to receive either DIM (108 mg per day in one study) or a placebo.

DIM was found to significantly alter the mix of estrogen metabolites, increasing “good” estrogen metabolites, and reducing “bad” estrogen metabolites.

DIM has also been evaluated for prevention of cervical cancer.5,7,28

In one remarkable study, women with a cervical precancer lesion—cervical intraepithelial neoplasia—were randomized to receive either 100 mg of DIM, 200 mg of DIM, or a placebo. After three to six months, all patients’ cervical intraepithelial neoplasia resolved completely with the 200 mg dose of DIM. With the lower 100 mg dose of DIM, 90.5% regressed.7

What you need to know

Researcher using syringe to extract compounds from broccoli

Maximizing the AntiCancer Effects of Cruciferous Vegetables

  • Cruciferous vegetables, such as broccoli, cabbage, cauliflower, Brussels sprouts, and kale, are associated with reduced risk of cancer.
  • Two cruciferous compounds are especially well-validated for their cancer-fighting properties: sulforaphane and 3,3’-diindolylmethane (DIM).
  • While DIM is stable, sulforaphane rapidly degrades if not absorbed quickly.
  • Scientists have developed a way to separately package a sulforaphane precursor and an enzyme that converts it into sulforaphane. The sulforaphane is then created in the small intestine, where it’s rapidly absorbed into the bloodstream.
  • Early research shows that DIM and bioavailable sulforaphane can prevent changes that lead to cancer, stop tumors from developing and spreading, and even cause cancer cells to die off.

Four Ways Sulforaphane and DIM Fight Cancer

What’s striking about sulforaphane and DIM is that they have demonstrated anticancer effects in virtually every tissue studied.

Equally impressive, these compounds can both prevent cancerous changes in cells, and in preclinical studies have been shown to reverse the progression of existing tumors.

These nutrients have been shown to reduce cancer risk in four main ways:

1. Preventing Harmful Changesto Gene Expression

Older man having physical done after epigenetic changes

Cancer can be caused by epigenetic changes, which can turn protective genes “off” and flip “on” genes that enable uncontrolled cellular proliferation. Adverse changes to gene expression can be triggered by behavior (like smoking) or exposure to environmental toxins.

Sulforaphane and DIM can reverse some of these cancer-associated changes.17

For example, sulforaphane reverses alterations of histone proteins involved in the regulation of genes that could otherwise contribute to cancer.29,30

This gene regulation mechanism is a target of cancer drugs now under development.31-33

2. Attacking Pre-Cancerous Cells and Blocking Tumor Development

Even after a cell starts down the path to cancer, its progression can be halted or reversed.

Sulforaphane has the ability to suppress signals and enzymes that spur the growth of tumors. It can also reduce the formation of blood vessels that feed them.34-39

DIM also has been shown preclinically to block the formation of new blood vessels in tumors, starving them of oxygen and nutrients needed to grow.40

Both sulforaphane and DIM also turn on genes associated with cancer cell apoptosis (programmed cell death). This causes the abnormal cells to die off, while leaving healthy cells unharmed.41,42

It is believed that these effects could prevent pre-cancerous cells from developing into cancer and slow the growth of existing cancer.

3. Fighting Estrogen-Driven Cancer Growth

An estrogen metabolite called 16-alpha hydroxyestrone can stimulate proliferation of breast and prostate cancers.43-45

DIM helps shift the estrogen balance away from 16-alpha hydroxyestrone that promotes cancer and toward one (2-hydroxyestrone) that inhibits it.27

In women who have had breast cancer, daily DIM intake shifts these estrogen metabolites toward a preponderance of the healthier form.27

In men, higher estrogen levels are associated with prostate enlargement and cancers. Studies show DIM can prevent estrogen-induced stimulation of prostate cancer cells.46,47

Sulforaphane reinforces this protection by fighting the potential DNA-damaging effects of estrogen, which could help to prevent the early DNA damage that leads to cancers.48-50

4. Blocking a Key Inflammatory ‘Switch’

Our bodies have a “switch” that activates inflammation, including chronic inflammation that contributes to cancer and other age-related diseases.

This switch is called nuclear factor-kappa B (NF-kB).

Preliminary research shows that sulforaphane blocks NF-kB, reducing the inflammation that contributes to cancer growth. It also kills cancer stem cells that can trigger tumor recurrence.12,51,52

These mechanisms are likely reasons why sulforaphane and DIM are two of the most robust cancer-fighting compounds found in nature.

Summary

Older couple cooking with broccoli for beneficial compounds

Raw cruciferous vegetables like broccoli are associated with a reduced risk for many types of cancers.

Many of these anti-cancer effects are due to two compounds derived from these vegetables: sulforaphane and DIM.

DIM is stable and easily absorbed when taken orally. But sulforaphane is not.

Scientists have solved this problem by creating a delivery system that separates a sulforaphane precursor and an enzyme that converts it to sulforaphane.

This enables sulforaphane to be formed in the small intestine where it can be rapidly absorbed, delivering higher blood levels of the beneficial 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.

Sulforaphane May Help Prevent Alzheimer’s Disease

Preclinical research suggests that sulforaphane may help prevent some of the pathogenic factors that lead to Alzheimer’s disease.

A review published in the March 2021 issue of International Journal of Molecular Sciences noted that sulforaphane, known for its anti-inflammatory effects, has recently been studied for its effects on brain health.53

Dr. Jiyoung Kim, the scientist who conducted this study, pointed out that changes occur within the brain 10-15 years before the cognitive decline that leads to a diagnosis of Alzheimer’s.

For this reason, she focused on studies that investigated the effects of sulforaphane on five different preclinical biomarkers for Alzheimer’s: beta amyloid, tau, inflammation, oxidative stress, and neurodegeneration.53

  • Most significantly, cell and animal studies demonstrated that sulforaphane can prevent the production of both beta amyloid and tau, proteins involved in Alzheimer’s disease.
  • Evidence also showed that sulforaphane inhibits the Alzheimer’s-associated preclinical biomarkers of inflammation, oxidative stress, and neurodegeneration.

These effects were seen in many different cell and animal models. This suggests that there is a future possibility of an effective, sulforaphane-based strategy for Alzheimer’s prevention.

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