Debunking the Sulforaphane Cancer Link

A lot has been said about the Sulforaphane (found predominantly in cruciferous vegetables) and Cancer link. Studies have been performed to identify the effect Sulforaphane has on procarcinogens, it’s usage as a detoxification tool and a preventative against DNA damage. Here we look at Sulforaphane as a preventative and therapeutic tool against cancer, and demystify a lot of the confusion around this complex and developing topic.

Read more

Sulforaphane and cancer: is there a link between sulforaphane (found in cruciferous vegetables) and cancer?

Sulforaphane has been growing in prominence because of its potential as a super supplement.

There are indications to suggest that it can positively affect various aspects of your health, including pollution detoxification, anti-aging, and brain health, just to name a few [1].

But one of the areas where sulforaphane has garnered the most attention is its potential to fight against cancer. And from what we know so far, there are definitely some encouraging signs.

But as with all things in the age of the internet and social media, the potential benefits often get misrepresented by health influencers and supplement companies trying to sell you products or increase their follower numbers.

And when it comes to something as sensitive as cancer, misinformation can become a matter of life and death.

That is why we want to take this opportunity to debunk any myths about sulforaphane and cancer.

Below, we’ll discuss what is sulforaphane, how it works, how it may be beneficial in cancer prevention, and also what you need to know about the limitations of the evidence so far.

We’ll also list some additional tips like the most trusted sources on sulforaphane research, and how to increase the bioavailability of sulforaphane from food sources.

What is sulforaphane?

Sulforaphane is a plant compound that’s rich in sulfur, and it is found predominantly in cruciferous vegetables [2].

But it gets a bit more complicated than that. Because you have to “activate” sulforaphane when you eat cruciferous vegetables like broccoli, cauliflower, kale, cabbage, etc.

So, let’s take a step back and take a quick look at the entire process.

Sulforaphane and glucoraphanin

Cruciferous vegetables have these plant compounds known as glucosinolates. The type of glucosinolate that forms sulforaphane is known as glucoraphanin [3].

When you eat broccoli, you activate a process that turns glucoraphanin into sulforaphane.

How does that happen? When you chew, chop, or crush cruciferous vegetables, you activate an enzyme known as myrosinase [4].

Try new Sulforaphane supplement for FREE: uVitals has developed & clinically tested a new Sulforaphane Supplement. Sulforaphane benefits include the reduction of gut inflammation, possible prevention of cancer cell growth and even the detoxification of air pollutants in cities with poor air quality.

We want to get it in the hands of users who can provide us critical feedback so we are providing FREE samples to those who apply to our beta program by clicking here.


Myrosinase is responsible for transforming glucoraphanin into sulforaphane, the compound linked with all the different health benefits.

So, let’s take a quick recap.

Broccoli has glucoraphanin → you chew or chop broccoli → the enzyme myrosinase is activated → myrosinase turns glucoraphanin into sulforaphane → Your body absorbs sulforaphane and you enjoy the potential health benefits.

In the next section, we’ll talk about how might sulforaphane work to prevent cancer, and what the current research tells us.

How might sulforaphane help prevent cancer?

Before we get started, it is important to note that you must consult your doctor first if you are considering taking sulforaphane as a cancer-preventive supplement.

Sulforaphane might help prevent cancer in a few different ways.

It can prevent the formation of carcinogens, it can also help your body get rid of carcinogens, and it can also prevent DNA damage, all of which might help prevent cancer.

Sulforaphane and procarcinogens

You’re probably familiar with the term carcinogens. It’s the harmful substance that promotes cancer within the human body.

But did you know that we don’t actually inhale or consume carcinogens directly? Instead, we take in procarcinogens that then turn into carcinogens in the body.

For example, when you breathe polluted air or smoke cigarettes, you’re inhaling procarcinogens.

Another example is nitrites from cured and processed meat, which is a procarcinogen. But it can turn into nitrosamine inside the body, which is a carcinogen.

So what does sulforaphane have to do with all of this? It can prevent the transformation of procarcinogens into carcinogens, thereby potentially reducing your risk of cancer [5].

There’s something called the phase I biotransformation enzymes that are responsible for turning procarcinogens into carcinogens [6].

Sulforaphane may play a role in the deactivation of these phase I biotransformation enzymes, which could then prevent the transformation of procarcinogens to carcinogens.

Sulforaphane and detoxification

Not only can sulforaphane prevent the formation of carcinogens, but it can go one step further and remove carcinogens from your body.

Sulforaphane induces something known as the NRF2 pathway [7]. NRF2 plays a vital role in many important functions within the body, like the regulation of antioxidants to protect your cells from oxidative damage [8].

NRF2 also activates something known as the phase II detox enzymes, which help flush your body of carcinogens [9].

Sulforaphane, DNA damage, and cancer prevention

Another possible way that sulforaphane might help prevent cancer is through the prevention of DNA damage.

One of the phase II detox enzymes activated by NRF2 (when you consume sulforaphane) is glutathione-S-transferase [10].

Glutathione-S-transferase can do a couple of different things that are relevant to cancer.

It can deactivate procarcinogens so it doesn’t turn into cancer-causing carcinogens. The procarcinogens are instead transformed into compounds that are flushed through bile and urine.

The process of excreting procarcinogens ends up having an anti-inflammatory effect that can prevent DNA damage [11].

Reducing DNA damage is a very good thing for many reasons, like anti-aging. But it may also reduce your risk of cancer.

What does the research say about sulforaphane and cancer prevention?

So far, we’ve discussed how sulforaphane might reduce your risk of cancer. Now let’s take a look at some of the existing research when it comes to sulforaphane and cancer.

Reduced risk of lung cancer in smokers

Earlier, we explained how sulforaphane prevents procarcinogens from turning into cancer-causing carcinogens.

A case-controlled study published in BMC Cancer Journal points to similar conclusions [12].

The researchers conducted a hospital-based study with lung cancer cases and controls based on smoking status. The study was further adjusted based on smoking duration, intensity, etc. The study included a total of 948 cases and 1743 control cases.

Both groups, the lung cancer cases, and controls were given detailed questionnaires that covered a variety of lifestyle factors.

Both groups reported on their alcohol and tobacco usage, occupational history, medical history, family history of cancer, demographic information, etc.

They also answered a 44-item food frequency questionnaire (FFQ) about their diet a few years before the study.

Not surprisingly, those who consumed more fruits and vegetables were at a lower risk of lung cancer compared to those who ate less.

But when it comes to sulforaphane, what was interesting was that the participants who consumed more cruciferous vegetables had a 55 percent lower risk of lung cancer even if they were smokers.

The researchers concluded that there was significant enough evidence to suggest an inverse association between cruciferous vegetable consumption and lung cancer risk among smokers.

Sulforaphane and benzene excretion

Another study in China demonstrated that sulforaphane can significantly increase the excretion of air pollutants like benzene from the body [13].

In a 12-week randomized clinical trial with 291 people, participants drank a daily broccoli sprout beverage containing glucoraphanin and sulforaphane. So, they included both the precursor to sulforaphane (glucoraphanin), and sulforaphane itself, to increase bioavailability and potency.

The participants were recruited from an area in China with a substantial amount of air pollution that had been associated with an increased risk of lung cancer.

After only one day of drinking the broccoli sprout drink, participants experienced an increase in the rate of excretion of benzene by more than 60 percent.

Benzene is a carcinogen. As we explained above, sulforaphane can not only prevent procarcinogens from turning into carcinogens, but it can also promote the excretion of carcinogens from the body with the help of phase II detox enzymes.

Major sources of benzene are air pollution caused by automobile exhaust and cigarette smoke (including secondhand smoke).

By helping flush benzene from the body, it is possible that sulforaphane could reduce the risk of cancer in residents in similarly polluted parts of the world.

Caution about sulforaphane and cancer

Above, we’ve listed all the different ways that sulforaphane might reduce cancer risk, and also a few studies that point towards evidence suggesting the same.

You get sulforaphane from cruciferous vegetables (although not always, more on that below) and broccoli sprouts. And for most people, it would be a good idea to consume them regularly.

But what you shouldn’t do is automatically assume that you’re safe from cancer because you’re eating broccoli and cauliflower.

Cancer is a complex condition with various risk factors. And as we mentioned above, your doctor is the ultimate authority when it comes to your specific cancer prevention plan.

That being said, many people wonder whether sulforaphane can be therapeutic for cancer.

Preventive vs. therapeutic

A very important distinction to keep in mind is the difference between sulforaphane potentially being preventive for cancer as opposed to therapeutic.

Everything we’ve discussed so far has been focused on reducing your risk of cancer. Not treatment or therapy if you’re already diagnosed with cancer.

Not enough therapeutic evidence

Even the most ardent proponents of sulforaphane say that there is not enough evidence, or any scientific consensus, to suggest that sulforaphane has therapeutic effects for cancer.

Dr. Jed Fahey, Assistant Professor at Johns Hopkins University School of Medicine, Division of Clinical Pharmacology, is one of the leading researchers on the topic of sulforaphane.

On a recent podcast episode with Dr. Rhonda Patrick, Ph.D. in biomedical science and expert on nutritional health, Dr. Fahey was asked this very question – Is sulforaphane therapeutic for cancer?

He said that while there is research that is currently underway, it is too soon to come to any conclusions from the very limited data.

What if I’m already diagnosed with cancer?

Dr. Fahey went one step further and cautioned against consuming too much sulforaphane for people already diagnosed with cancer.

We know that sulforaphane activates NRF2, which regulates antioxidants and protects cells from oxidative damage.

Activating too much NRF2 might end up protecting the wrong type of cells in someone receiving cancer treatment.

Cancer cells that are metastasized grow faster than the cells around them. Too much NRF2 might end up supporting this process further and help the cancer cells detoxify the effects of cancer drugs.

But Dr. Fahey concluded by saying that we simply don’t know enough yet, and hopefully, soon we will learn more about any potential therapeutic effects of sulforaphane.

So, is sulforaphane effective against cancer?

As we’ve discussed above, there’s evidence to suggest that sulforaphane might reduce your risk of cancer through the following mechanisms.

  • By stopping procarcinogens from turning into carcinogens
  • By promoting detox and flushing of carcinogens from the body
  • By preventing DNA damage

But things are a lot more uncertain when it comes to the question of whether sulforaphane can be therapeutic against cancer. We currently don’t have enough data or evidence to suggest any therapeutic effects. And there is also no consensus among the researchers.

So, until there is more evidence and scientific consensus, you should assume that sulforaphane has no therapeutic effects for cancer.

As Dr. Fahey warns, you should be careful about consuming too much sulforaphane if you’re already diagnosed with cancer. You don’t want to inadvertently end up supporting metastasized cancer cells.

What are the other benefits of sulforaphane?

Adding sulforaphane to your diet is most likely a good idea regardless of your risk of cancer.

As explained above, at the very least, it might flush any environmental pollutants like air pollution or secondhand smoke.

But beyond that, there are also other benefits of consuming cruciferous vegetables and sulforaphane.

  • Reduced risk of respiratory ailments like asthma [17]
  • Cognitive benefits like reduced risk of depression and schizophrenia [18]
  • May boost heart health [19]

Who can I trust on the topic of sulforaphane and cancer?

Two of the most trusted sources of information on sulforaphane are the two people we’ve already mentioned above.

Dr. Jed Fahey and Dr. Rhonda Patrick.

When new evidence on sulforaphane emerges, you can rest assured that you will hear it first from them. And that you’ll get nothing but the proven facts, so you can make informed health decisions for yourself.

Here’s where to find them:

Dr. Jed Fahey – Assistant Professor at Johns Hopkins University School of Medicine, Division of Clinical Pharmacology. Dr Jed Fahey twitter

Dr. Rhonda Patrick – Ph.D. in biomedical science and expert on nutritional health. Dr Rhonda Patrick twitter Dr Rhonda Patrick Youtube Channel

What are the best dietary sources of sulforaphane?

Technically, cruciferous vegetables are the best sources of sulforaphane. So, vegetables like broccoli, kale, cauliflower, cabbage, etc.

Some studies show that people who eat a lot of cruciferous vegetables have been found to have a lower risk of cancer.

But it could all depend on how you like your broccoli. If you like to heat your cruciferous vegetables, like most people, then you might be missing out on most of the sulforaphane.

The reason for that has to do with the enzyme myrosinase.

uvitals may earn revenue if you click the links and buy the products featured on this page. Find out more

The myrosinase factor

As we explained before, you activate sulforaphane in cruciferous vegetables when you chew, chop, or crush them.

You activate the myrosinase enzyme, which turns glucoraphanin into sulforaphane. The problem is that heat destroys the myrosinase enzyme [14]. That means when you heat your broccoli or cauliflower, a lot of glucoraphanin is not getting converted to sulforaphane.

If you want to maximize sulforaphane, you have a few different options. Unless you’re regularly eating raw cruciferous vegetables.

Broccoli sprouts

Sprouted broccoli seeds are one of the most potent sources of sulforaphane with maximum bioavailability.

The best part is that it is affordable, and a relatively simple process.

Dr Rhonda Patrick & Dr Jed Fahey have put together an excellent easy-to-follow guide on how to sprout your own broccoli seeds for maximum sulforaphane.

You can buy broccoli seeds online (Todds seeds come highly recommended due to their high germination rate), as well as sprouting kits. Overall it is quite a simple process.

sulforaphane supplement

Get uVitals Sulforaphane supplement for FREE: we have developed a new Sulforaphane Supplement, allowing you to conveniently get the benefits of sulforaphane daily, like the reduction of gut inflammation and even the detoxification of air pollutants in cities with poor air quality!

We want to get uVitals Sulforaphane in your hands so you can provide critical feedback, so we are providing FREE samples to those who apply to our beta program by clicking here.

Sulforaphane supplements

If you can’t grow your own sprouts, you can take a sulforaphane supplement.

But try to avoid ones that only have sulforaphane in them because their bioavailability is typically not that high. If you’re going to take a sulforaphane supplement, go with one that also contains myrosinase to increase absorption.

Dr Rhonda Patrick’s Sulforaphane supplement of choice, due to it’s inclusion of the myrosinase enzyme, is Avmacol.

Avmacol Sulforaphane Supplement
Avmacol was developed in conjunction with a Johns Hopkins trained scientist & has been used in various clinical studies. It’s also Dr Rhonda Patrick’s favorite sulforaphane supplement containing broccoli seed & sprout extract, myrosinase + Vitamin C

Add mustard seeds to cruciferous vegetables

Adding raw ground mustard seeds to cooked broccoli increased the bioavailability of sulforaphane by four times [15].

Mustard is also a part of the cruciferous family, and the seeds also contain the myrosinase enzyme.

So, when you add raw ground mustard seeds to cooked broccoli, the myrosinase from mustard seeds can interact with the glucoraphanin in broccoli to make the sulforaphane more bioavailable to you. And you can easily buy organic mustard seeds online.

Moringa, myrosinase, and sulforaphane

For a potent combination of antioxidants and anti-inflammatory compounds, try to combine sulforaphane with myrosinase, and moringa tea in your diet.

Like sulforaphane, moringa tea also has a phytochemical known as moringin, which may have similar disease preventive properties [16].

But moringin in moringa is also dependent on myrosinase, which is also heat-sensitive in moringa. So, try to opt for a cold-brewed moringa tea to get the maximum moringin.

Dr Jed Fahey recommends moringa products from Kuli Kuli, as their products use a high-quality source of moringa leaf powder to avoid possible microbial contamination. Kuli Kuli make organic pure moringa powder, moringa smoothie mixes and moringa tea in several flavors.

Organic Pure Moringa Vegetable Powder
Moringa is a tropical plant native to central and southern Asia. There is scientific evidence suggesting that moringin, a compound derived from moringa, may provide protection against chronic diseases, such as cancer and diabetes, and may be useful in treating the symptoms of mental disorders, such as schizophrenia or autism. Kuli Kuli use a high-quality source of moringa leaf powder in their products to avoid possible microbial contamination.

Key takeaways from research of the Sulforaphane Cancer link

Research suggests that sulforaphane could be responsible for many of the benefits of cruciferous vegetables. As we’ve discussed in this article, one of the biggest potential benefits of consuming sulforaphane could be a reduced risk of cancer.

But remember that the research is still ongoing, and it is too early to suggest that sulforaphane can be effective against cancer. Especially in terms of therapeutic effects.

That being said, there are numerous benefits to eating a diet rich in cruciferous vegetables. They have been shown to have anti-inflammatory and antioxidant effects, improved cardiovascular health, brain health, among other benefits.

For an added boost, combine with moringa and myrosinase to maximize the antioxidant and anti-inflammatory effects of sulforaphane.

Products mentioned in this article

Resources mentioned in this article

Agnit is the lead writer for uVitals. As an avid health and fitness enthusiast, he is passionate about writing content that helps people take control of their health to live happier, more productive lives. Someday, he plans to listen to his own advice and drink less coffee.

What supplements does Dr. Rhonda Patrick take?
Sulforaphane broccoli sprouts guide
Sulforaphane Supplements
Is there a sulforaphane cancer link? We look at sulforaphane, found in cruciferous vegetables has any effect on cancer according to current research
Jed Fahey Sulforaphane & Moringa recommendations
The benefits of Sulforaphane according to Jed Fahey & Rhonda Patrick
Can Sulforaphane stop hair loss?

Leave a Comment