Life Extension Magazine®

Woman supplementing with cruciferous vegetables

Anti-Cancer Nutrients Found in Cruciferous Veggies

Death rates from cancer are down, but the number of Americans dying each year is higher than ever. A new method enables people to achieve higher blood levels of anti-cancer nutrients found in cruciferous vegetables.

Scientifically reviewed by Dr. Gary Gonzalez, MD, in August 2023. Written by: William Faloon.

William Faloon
William Faloon

The American Cancer Society made a big announcement earlier this year:

Cancer death rates for men and women plummeted 27% between 1991 and 2016.1

This is exciting news but overlooks the fact that more Americans are dying of cancer than ever before.2 A record 607,000 cancer deaths will occur in the United States this year.1

Not factored into these numbers are side effects inflicted by surgery, radiation, chemotherapy, and newer immune-modulating drugs like Keytruda®.

These side effects go beyond the miseries suffered during conventional treatment. Many patients exposed to these therapies are at increased risk of heart failure and secondary malignancies.

For example, breast cancer patients treated with radiation and certain chemo drugs have up to a 4.2-fold increased risk of leukemia that is often difficult to cure.3

So, while cancer death rates declined 27% since 1991, more Americans than ever before are being diagnosed with cancer and aggressively treated.

We at Life Extension® advocate for proactive prevention. A lot starts with healthy diet, including consumption of cruciferous vegetables that are rich in cancer-fighting compounds.4

In a major advance, a new cruciferous vegetable formula enables people to achieve higher blood levels of anti-cancer nutrients than ever before.

Transformative potential now exists to reduce the number of newly diagnosed malignancies, as opposed to more effectively treating those who fall victim.

Cruciferous vegetables have long been known to reduce one’s risk of developing cancer.5-8

A partial list of cruciferous vegetables includes kale, cabbage, Brussels sprouts, cauliflower, watercress, and broccoli.

These plants contain anti-cancer components, as demonstrated by hundreds of published studies.9,10

The challenge has been to identify growing conditions, cooking methods, and even how to eat these plants in order to obtain optimal amounts of active anti-cancer compounds.11

Why Vegetable “Sprouts and Seeds” Are Beneficial

Broccoli Sprouts

Vegetables undergo a maturation process whereby their biochemistry changes with age.

As vegetables sprout from seeds, they naturally express nutrients that have been shown to be especially protective against cancers.

Broccoli sprouts and seeds contain huge amounts of a compound called glucoraphanin and a critical enzyme called myrosinase.

This enzyme is needed to transform glucoraphanin into an anti-cancer compound called sulforaphane.12

The sequence is as follows:

Broccoli seeds or sprouts




The glucoraphanin content of broccoli dramatically diminishes as the plant grows into the familiar vegetable we see at the market.12

Excited by the anti-cancer potential of glucoraphanin, researchers began to study broccoli sprouts to better understand potential therapeutic applications.

Formation Pathway of Anti-Cancer Compounds In Cruciferous Vegetables

Broccoli sprouts and seeds contain large amounts of glucoraphanin that is converted by the myrosinase enzyme into an anti-cancer compound called sulforaphane.12-14

Mature broccoli also contains these anti-cancer compounds, but in far smaller amounts.

How Sulforaphane Was Discovered

In 1992,15 scientists at Johns Hopkins showed that three-day-old broccoli sprouts contain 10 to 100 times higher the amount of anti-cancer compounds compared to mature broccoli.12

These scientists were the first to isolate and patent high-potency sulforaphane for its cancer prevention properties.16,17

They showed that female rats administered sulforaphane developed fewer, smaller, and slower growing tumors compared with controls. This study found that after rats were exposed to a potent carcinogen, a double dose of sulforaphane reduced tumor incidence and number by more than 50% compared with controls.18

Researchers later discovered that broccoli seeds have an even higher content of glucoraphanin than broccoli sprouts.19

Most People Eat Broccoli Wrong


More people eat broccoli today than ever before. Yet few derive maximum benefits.

One reason is that the cooking of broccoli reduces broccoli’s beneficial components. These include glucoraphanin and myrosinase that convert to biologically-active sulforaphane.20

Another cruciferous compound is I3C (indole-3-carbinol). It also requires the myrosinase enzyme to fully activate. I3C has demonstrated profound anti-cancer effects in rats.12,21

I3C itself is not particularly stable, but quickly converts to a beneficial compound called DIM (3,3’-diindolylmethane). DIM has demonstrated hormone-modulating properties that have cancer-fighting effects.22,23

To derive maximum benefits from broccoli sprouts or mature florets, eat them raw and chew them well.

A less expensive and more convenient method is to ingest a new cruciferous formula that delivers higher potencies of sulforaphane and DIM into the human bloodstream.

Take-Home Lesson About Sulforaphane

Published studies show sulforaphane is the compound in broccoli with the most demonstrated cell-protecting benefits.24-36

The amount of sulforaphane people obtain when eating mature broccoli or even broccoli sprouts is trivial when compared to a newly designed cruciferous formula.37,38

To understand why people aren’t benefiting more from cruciferous vegetables, one must understand limitations that prevent significant amounts of anti-cancer compounds from being delivered into the bloodstream.

In the broccoli plant there are separate cell compartments that contain glucoraphanin and the enzyme myrosinase.39

With chewing, these broccoli cell compartments rupture and glucoraphanin is exposed to the myrosinase enzyme that converts it to sulforaphane.

Sulforaphane is absorbed into the bloodstream mostly in the small intestine.40,41

When one eats broccoli, the myrosinase enzyme quickly converts glucoraphanin to sulforaphane. Beneficial sulforaphane, however, is an unstable compound that is highly susceptible to degradation.42

Cancer Risk Reduction with Cruciferous Vegetables

The following percentages of cancer risk reduction are based on dietary intake of people ingesting the highest versus the lowest amounts of cruciferous vegetables.

They do not reflect the potential benefits of a newly designed formulation that enables higher quantities of bioavailable sulforaphane to be absorbed into the blood.  

Cancer Risk Reduction
Colorectal 49%48
Melanoma 46%49
Prostate 42%50
Pancreas 34%51
Kidney 32%52
Bladder 31%53
Esophagus 28%54
Ovary 24%55
Lung 22%56
Breast 17%54
Mouth and Throat 17%54

Why Sulforaphane Is Not Better Absorbed

The conversion of glucoraphanin into sulforaphane varies greatly with plant maturity and freshness. A lot depends on the amount of myrosinase and glucoraphanin in a cruciferous vegetable on a given day.13,43,44

Conversion to sulforaphane is never 100% because raw broccoli plants contain additional ingredients that support formation of inactive compounds rather than the beneficial sulforaphane.42

Thus, only a small amount of sulforaphane from ingested broccoli makes it to the small intestine for optimal absorption into the blood.

When looking at the substantial reductions in cancer risk in people who eat the highest amount of cruciferous vegetables, there is enormous potential to prevent more cancers by delivering higher levels of sulforaphane.

A new technology does just that by keeping myrosinase and glucoraphanin separate until they reach the small intestine, where they combine to provide far higher amounts of sulforaphane.

Findings from Human Study

In a study done at Johns Hopkins, healthy people were given glucoraphanin alone or combined in a special preparation with the myrosinase enzyme.13

Average age of study participants was 54 years and urinary metabolites of sulforaphane were used to assess bioavailability.

Bioavailability of glucoraphanin alone was about 10%, which is good. This means that about 10% of ingested glucoraphanin was converted into sulforaphane. However, when conversion to sulforaphane relies solely on gut enzymes there is large variability among subjects.13

When preparations that contained glucoraphanin were combined with myrosinase, the findings showed bioavailability increased from 10% to about 35%. This translates into a greater than 3-fold increase in cancer-fighting sulforaphane.13

Gene Regulation

Image of a gene

Recent studies reveal cruciferous compounds regulate genes that are responsible for the uncontrolled proliferation and survival of various types of cancer cells.36,40,45

We now know that cruciferous compounds favorably regulate genes that control cell proliferation.

Gene regulation is one of several anti-cancer mechanisms possessed by these vegetable extracts.46

Sulforaphane and DIM have been found to reverse many of the cancer-associated DNA methylation alterations, including aberrantly methylated genes that are dysregulated or  involved in cancer progression.47

Shield Against Environmental Carcinogens

vegetables being sprayed with chemicals

Herbicides, pesticides, drinking water, plastics, and industrial emissions contain cancer-causing toxins.57

These chemicals lead to cancer by damaging our DNA and impeding our detoxification pathways.58-61

It is virtually impossible to avoid the onslaught of environmental toxins.

It is possible, however, to equip your body with the tools it needs to target toxins and remove them before they cause serious damage.

Cruciferous vegetables do just that. They optimize crucial aspects of the body’s detoxification system to neutralize many chemical threats—and maintain the integrity of cellular DNA in the process.40,62,63

Decades of research show that consuming cruciferous vegetables can slash risk of cancer. These findings reveal reduced risk of virtually every major type of cancer.36,40,64

Overcome Limitations On Cancer Risk Reduction

There is no doubt that cruciferous vegetables contain cancer-preventing compounds.

Yet the most favorable data show only up to a 49% reduction in cancer incidence in those who eat the most broccoli, cauliflower, etc.48,49,52-56

My concern is that even people who eat plenty of vegetables still have significant cancer risks. And most people are challenged to eat lots of cruciferous vegetables on a consistent basis.

This makes the advent of the first technology that separates myrosinase from glucoraphanin so exciting. It greatly increases the amount of bioactive sulforaphane that can be readily absorbed in the small intestine.

Up until recently, myrosinase was not available in stable form. Few companies provide this enzyme together with glucoraphanin.

And no one is separating myrosinase from glucoraphanin to ensure optimal conversion to sulforaphane in the small intestine for maximum absorption.

Another limitation is that cruciferous vegetables are often cooked or frozen, which reduces the amount of glucoraphanin and destroys the myrosinase needed to transform glucoraphanin into sulforaphane.37,38

Why Not Take Sulforaphane?

You may ask: why not just ingest sulforaphane itself?

The reason this is not practical is that sulforaphane is highly reactive and unstable. A person would have to specially prepare and ingest fresh sulforaphane within minutes.13,65

Sulforaphane’s instability also means a limited “shelf-life” and it would be unfeasible for a supplement formula.

Thus, ideally, we don’t want sulforaphane produced until it reaches the small intestine where it gets optimally absorbed quickly.

A new formulation that compartmentalizes and then properly releases myrosinase plus glucoraphanin is the ideal method of delivering sulforaphane body.

Transformative Potential

When one studies the beneficial effects of sulforaphane, there is now transformative potential to reduce the number of newly diagnosed malignancies.

For newly diagnosed cancer patients, an article in this month’s issue describes the benefit of storing one’s bone marrow stem cells prior to conventional treatments.

Another article highlights how cruciferous vegetables protect against chronic inflammation, and even aging.

We also present recent findings on two drugs that show improved survival in breast and prostate cancer patients, and describe how excess bone loss can fuel cancer cell propagation.

Despite these favorable discoveries, more than 600,000 Americans are losing their lives each year in this ongoing cancer “war.”

We at Life Extension® advocate for more cancer research and intelligent translation of favorable findings into clinical practice, so that more human lives can be spared.

For longer life,

For Longer Life

William Faloon, Co-Founder
Life Extension® Buyers Club


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