In this episode, we discuss:
- Background on sulforaphane
- Health benefits of sulforaphane
- How sulforaphane is 80 times more bioavailable than known detoxifying compounds
- How to incorporate sulforaphane into your diet
- A step-by-step tutorial on how to make broccoli sprouts
- Supplementing with sulforaphane
- “Broccoli or Sulforaphane: Is It the Source or Dose That Matters?” published in Molecules
- “Current Landscape of NRF2 Biomarkers in Clinical Trials” published in Antioxidants
- “Transcriptional Regulation by Nrf2” published in Antioxidants & Redox Signaling
- “Nrf2 targeting by sulforaphane: a potential therapy for cancer treatment” published in Critical Reviews in Food Science and Nutrition
- “Sulforaphane and Other Nutrigenomic Nrf2 Activators” published in Oxidative Medicine and Cellular Longevity
- “Potential effects of sulforaphane to fight obesity” published in The Journal of the Science of Food and Agriculture
- “Effect of Sulforaphane in Men with Biochemical Recurrence after Radical Prostatectomy” published in Cancer Prevention Research
- “Inhibition of Urinary Bladder Carcinogenesis by Broccoli Sprouts” published in Cancer Prevention Research
- “Sulforaphane, a Dietary Component of Broccoli/Broccoli Sprouts, Inhibits Breast Cancer Stem Cells” published in Clinical Cancer Research
- “Chemoprevention of colonic aberrant crypt foci in Fischer rats by sulforaphane and phenethyl isothiocyanate” published in Carcinogenesis
- “Can Activation of NRF2 Be a Strategy against COVID-19?” published in Trends in Pharmacological Sciences
- “Sulforaphane Augments Glutathione and Influences Brain Metabolites in Human Subjects: A Clinical Pilot Study” published in Molecular Neuropsychiatry
- “Sulforaphane Modulates Joint Inflammation in a Murine Model of Complete Freund’s Adjuvant-Induced Mono-Arthritis” published in Molecules
- “Sulforaphane prevents angiotensin II-induced cardiomyopathy by activation of Nrf2 via stimulating the Akt/GSK-3ß/Fyn pathway” published in Redox Biology
- “Sulforaphane improves endothelial function and reduces placental oxidative stress in vitro” published in Pregnancy Hypertension
- “Sulforaphane Protects against Cardiovascular Disease via Nrf2 Activation” published in Oxidative Medicine and Cellular Longevity
- “Bioavailability and inter-conversion of sulforaphane and erucin in human subjects consuming broccoli sprouts or broccoli supplement in a cross-over study design” published in Pharmacological Research
- “Sulforaphane – role in aging and neurodegeneration” published in GeroScience
Hey, everyone, Chris Kresser here. Welcome to another episode of Revolution Health Radio. This week, I’m going to do another solo episode. I did one last week, which I hope you heard, on glyphosate, and we got some good feedback on that. And the topic for this week also lends itself well to that solo format. So I’m going to do it again.
In that last episode, we talked about why glyphosate-based herbicides like Roundup are one of the most dangerous toxins that we’re exposed to, and what the most recent scientific research tells us about glyphosate’s effects on human health. I reviewed the overwhelming evidence suggesting that glyphosate is associated with increased risk of cancer, particularly non-Hodgkin’s lymphoma, and many other effects, including gut dysbiosis, which in turn drives many chronic diseases, hormone imbalance, impaired fertility, reduced detox capacity, nutrient deficiency, and oxidative stress to name a few. I shared some steps you can take to reduce exposure to glyphosate-based herbicides, like eating organic food as much as possible.
We also talked about the fact that it’s virtually impossible to entirely avoid glyphosate exposure in the modern world. And because of the significant potential for harm, it’s important to take steps to mitigate the exposure we can’t avoid. This includes things like eating a nutrient-dense anti-inflammatory diet, exercising regularly, getting enough sleep, reducing our exposure to other toxins, etc. But I think it also includes consuming additional nutrients that can upregulate our body’s internal detoxification system, especially by activating Nrf2 and improving glutathione status.
In this episode, we’re going to talk about one of the most potent compounds for doing this. It’s currently known to science [as] sulforaphane. You’ll learn what it is [and] why it’s such a powerful activator of our detox system and defender against toxins like glyphosate. [You’ll learn] how to get it from food (there’s really only one reliable way) and how to supplement with it properly, which is crucial because most sulforaphane supplements on the market are pretty much worthless, and there are many misleading and inaccurate claims made by supplement manufacturers in this field. You could argue [that] in most fields, but it seems to be particularly true when it comes to sulforaphane supplements. You’ll also learn about the many other benefits of sulforaphane, including how it protects the brain and restores cognitive function, reduces inflammation, slows the aging process, improves cardiovascular health, and even improves function in kids with autism spectrum disorder.
I have to admit, before I did a deep dive on sulforaphane, I was somewhat skeptical of the claims I had heard. People made it sound like some kind of miracle cure. But the more I’ve researched this molecule, the more impressed I am by its potential to both prevent and reverse disease, and to dramatically improve our health and well-being. It’s still not a miracle cure, of course, but it is one of the most promising therapeutic nutrients that I’ve come across in 15 years of doing this work. It’s my hope that after listening to this episode, you’ll be empowered with a potent new strategy for protecting yourself and your family, not only from the potential harms of glyphosate, but from other toxins and from the harmful impacts of this crazy modern world that we’re living in.
Okay, [one] last thing before we begin. As with the last episode, this one is a bit dense with a lot of science. I’ve done my best to make it accessible and easy to understand, but as always, I haven’t dumbed it down. I think it’s important for you to grasp the mechanisms so you know why sulforaphane is so powerful. And also, understanding these basics will help you to avoid wasting money on sulforaphane supplements that won’t actually increase sulforaphane levels in your body. Ready? Let’s dive in.
Background on Sulforaphane
Okay, let’s start with some basics. We’re going to get a few of these really complicated terms defined right up front so you’re not confused as you go through the episode. Sulforaphane is an isothiocyanate, which is a sulfur-containing organic compound. It’s derived from glucoraphanin, a glucose scintillate found in cruciferous vegetables such as broccoli, cabbage, cauliflower, Brussels sprouts, and kale. Sulforaphane is produced when glucoraphanin sulforaphane, which is also known as sulforaphane and glucosinolate, comes into contact with the enzyme myrosinase. Cutting or chewing broccoli, for example, can initiate the production of sulforaphane. In addition, myrosinase produced by our gut bacteria can also convert glucoraphanin to sulforaphane, although the efficiency of this conversion varies a lot from person to person and depends on the health of their gut flora.
For example, one study found that the ability of the gut flora to convert glucoraphanin that’s found in broccoli to sulforaphane varies between as low as 1 percent to as high as 40 percent. That’s a huge range and, unfortunately, there’s no way outside of a research setting to test yourself to see where you are on that spectrum. Neither clinicians nor consumers have any way of knowing if an individual’s gut flora is capable of converting glucoraphanin, the precursor form that you find in cruciferous vegetables, to sulforaphane, which is the active compound that we’re talking about here. This is absolutely critical to understand, because most supplements [that] claim to contain sulforaphane actually contain sulforaphane glucosinolate, which is the precursor form and requires the enzyme myrosinase to be converted to sulforaphane. If you take one of these supplements and you don’t have gut flora that effectively converts the precursors into sulforaphane, then you’re effectively just throwing money down the drain. And this together with the fact that sulforaphane degrades soon after it’s produced is what makes sulforaphane supplements so difficult to make. And it’s part of what leads to the many misleading claims out there about supplementing with sulforaphane. I’m going to come back to this in more detail later in the show.
So let me just pause and do a quick review because I know that was a lot of jargon. Sulforaphane is produced when glucoraphanins, which are precursor compounds found in cruciferous vegetables, come into contact with the enzyme myrosinase. Cutting, chewing, or sprouting broccoli can activate myrosinase and initiate the production of sulforaphane, and some people have myrosinase activity in their gut, which can have a similar effect. Most sulforaphane supplements contain sulforaphane precursors that need to be converted into the active form sulforaphane. But that conversion depends a lot on the gut flora and it’s unreliable because of the huge variation in myrosinase activity in the gut from person to person.
Health Benefits of Sulforaphane
Okay, so now let’s talk about the health benefits of sulforaphane before coming back to how to get more of it into your diet, or to supplement with it properly. Sulforaphane was discovered in 1992 at Johns Hopkins, and since then, there have been about 2400 research papers published on it in the peer-reviewed scientific literature. So far, 39 distinct prohealth mechanisms for sulforaphane have been discovered. And as I’ll explain shortly, many scientists in the field believe it’s a far more potent nutritional compound than others that you may have heard of, and may already be taking, or eating, like curcumin, resveratrol, and milk thistle or silymarin.
In this show, I’m going to focus on six primary benefits of sulforaphane plus one, what we might call a bonus benefit that’s especially relevant at this point in time. Number one, it lowers [the] risk of cancer. Number two, it upregulates our endogenous or internal detox capacity, and both of these first two benefits are especially relevant to reducing harm from glyphosate exposure. Number three, it protects the brain and restores cognitive function. Number four, it reduces inflammation. Number five, it slows the aging process. And number six, it improves cardiometabolic health. And lastly, the bonus benefit, as I’m calling it, is that it might be useful in our ongoing fight against COVID-19. So let’s start with cancer.
Sulforaphane has been shown to act against cancer at many different levels from the development to the progression of cancer. These effects include protection from DNA damage to altering the expression and activity of proteins related to cell cycle regulation, apoptosis, and angiogenesis. It also enhances the deactivation and excretion of carcinogens like glyphosate, for example. There have been numerous studies investigating the effects of sulforaphane in broccoli sprouts on cancer treatment. For example, in one trial of almost 80 men with prostate cancer, taking 60 milligrams of sulforaphane slowed the doubling rate of prostate-specific antigen [(PSA)] by a whopping 86 percent compared to placebo. Other studies looking at the effects of sulforaphane on cancers of the bladder, breast, and colon have found similar benefits. And many researchers now believe that sulforaphane is one of the most potent natural anti-cancer compounds that’s ever been discovered.
Number two is how sulforaphane improves detox capacity. Sulforaphane is one of the few natural compounds that works in all three phases of detoxification, which is a process that happens in every cell of the body. But while it works in all three phases, it’s the most potent phase two detoxifier of any currently known natural compound. This is critical because for safe and efficient detoxification, a toxin should move through a relatively slow phase one reaction, followed by a more rapid phase two reaction. During phase one, toxins are oxidized, reduced, or hydrolyzed into new metabolites and can be more effectively removed by the body. During phase two, these metabolites are conjugated into less toxic compounds. One of the biggest mistakes that can be made in a detox program is upregulating phase one without also upregulating phase two. This can lead to a buildup of toxic metabolites from the phase one reaction, which can make the situation worse rather than better. Unfortunately, this isn’t uncommon because many of the compounds that people typically consume for detox, like glutathione, folate, and niacin, stimulate phase one reactions but don’t increase phase two reactions. And this is why sulforaphane is so helpful for detoxification. It balances the effects of other compounds that are typically used for detox by increasing phase two reactions and preventing the buildup of toxins and their metabolites.
One of the primary ways that sulforaphane impacts detoxification is by activating Nrf2. Nrf2 is short for nuclear factor erythroid 2-related factor 2. I don’t know who was involved in naming these compounds, but thankfully, we have the acronym Nrf2. It’s a protein that regulates the expression of both antioxidant- and detoxification-related genes, and it’s been described by scientists as the master redox switch, and the guardian of healthspan and gatekeeper of longevity. Nrf2 controls the expression of over 200 genes involved in the antioxidant response. And research over the past two decades has shown it to be a key modulator of the cell’s primary defense mechanisms. It’s responsible for countering the effects of many harmful environmental toxins and carcinogens. Nrf2 is also responsible for sulforaphane’s activation of the phase two detoxification system, and unlike vitamin C, which has antioxidant effects that last for about one to two hours, sulforaphane’s effects last for up to 72 hours.
Number three is sulforaphane’s ability to protect the brain and improve cognitive function. Sulforaphane has been shown to increase brain-derived neurotrophic factor (BDNF) in mice. You’ve probably heard of BDNF by now. It supports the survival of existing neurons and encourages the formation of new neurons and synapses. And low levels of BDNF have been observed in many different conditions, such as autism, Alzheimer’s disease, Parkinson’s disease, anxiety, and brain trauma. Low BDNF has also been linked to accelerated aging, poor neural development, neurotransmitter dysfunction, obesity, depression, and even schizophrenia. Things like intense exercise, sun exposure, and avoiding processed and refined foods have all been shown to increase BDNF, but sulforaphane can have a particularly potent effect here.
Another way that sulforaphane protects the brain is by reducing brain inflammation, which is a big factor in neurodegenerative conditions. In particular, studies have shown that sulforaphane increases glutathione levels in specific regions of the brain, like the anterior cingulate cortex, hippocampus, and thalamus that tend to be involved in neurodegenerative problems. These effects explain why sulforaphane has been shown to improve learning and memory, boost cognitive function following a traumatic brain injury, protect against Alzheimer’s disease lesions in the brain, improve function in kids with autism spectrum disorders, and even reduce cognitive deficits seen in serious mental illnesses like schizophrenia.
The number four benefit is sulforaphane reduces inflammation. This is important because as I’m sure you know by now, inflammation is at the root of pretty much all modern chronic diseases. Sulforaphane protects against inflammation in two distinct ways. First, it inactivates nuclear factor kappa beta, or NFKB, which is a key inducer of inflammation, and second, as I mentioned a few minutes ago, sulforaphane is a potent activator of Nrf2, and Nrf2 contributes to the anti-inflammatory response by orchestrating the recruitment of inflammatory cells and regulating gene expression through the antioxidant response element. That’s a major antioxidant function that it has. So, as an example, in one study of mice, sulforaphane was shown to significantly reduce joint inflammation, and this is indeed one of the main clinical benefits that we see [while] using sulforaphane in our practice. People with all kinds of inflammatory conditions and pain tend to experience a pretty big reduction in those inflammatory symptoms.
Number five is that sulforaphane slows the aging process. Two of the main mechanisms of aging are oxidative stress and the degradation of proteasome function. We’ve already talked quite a bit about how sulforaphane protects against oxidative stress. As I just mentioned, it activates Nrf2, which in turn controls over 200 genes related to the antioxidant defense system. And this makes sulforaphane one of the most potent antioxidants that we know of. The proteasome is an intracellular system that’s responsible for cleaning up oxidized proteins that can cause oxidative stress. And research has shown that proteasome function is typically compromised during aging, it’s probably one of the mechanisms of aging, and that sulforaphane significantly enhances the function of the proteasome.
Number six, sulforaphane improves cardiometabolic health. It does this via several mechanisms, two of which we’ve already talked about, reducing inflammation and oxidative stress. But it also decreases insulin resistance, improves glucose tolerance, favorably affects lipid profiles, regulates cardiac muscle, improves endothelial function, and more. And specifically, several studies have shown that sulforaphane can reduce inflammation and cytokine production in people with metabolic disorders like obesity and type 2 diabetes. Sulforaphane has also been shown to improve dyslipidemia, decrease systolic blood pressure, lower plasma leptin, and decrease weight gain.
The last bonus benefit I want to talk about is related to COVID-19. A paper published almost a year ago in July 2020 posed the question, can activation of Nrf2 be a strategy against COVID-19? It pointed out that COVID-19 is characterized by an out of control inflammatory response, including a cytokine storm and a loss of T-lymphocytes. The authors speculated that an anti-inflammatory strategy characterized by Nrf2 could restore redox and protein homeostasis, promote resolution of inflammation, and facilitate tissue repair. They pointed out that sulforaphane is already being studied for these effects against COVID-19 in clinical trials. As far as I know, at the time of this recording in June 2021, none of these trials has been published yet. So we don’t have results. Having said that, given sulforaphane’s well-established effect of stimulating Nrf2 and Nrf2’s well-established anti-inflammatory role, it stands to reason that sulforaphane may have some protective effect in cases of COVID-19.
Another potential mechanism for sulforaphane’s protection against COVID-19 is TMPRSS2. Here we go with the acronyms again. [It’s] a protein on the cell membrane that activates viral spike proteins. So this is relevant to SARS-CoV-2 because it uses the ACE2 receptor for entry into the cell, and its spike protein is primed by TMPRSS2. Sulforaphane has been shown to decrease the expression of TMPRSS2, which then results in less surface protein to activate the binding of the virus to the human cell. So, while more research definitely needs to be done to confirm that these proposed mechanisms actually translate into real clinical benefit, sulforaphane is a promising potential intervention for COVID-19, and I look forward to seeing the results of the studies that are already underway.
Sulforaphane is 80 times more bioavailable than known detoxifying compounds. In this episode of RHR, we’ll discuss how you can incorporate sulforaphane into your diet and supplementation regimen to protect yourself and your family from environmental toxins, cancer, and disease. #sulforaphane #chriskresser
Sulforaphane Is 80 Times More Bioavailable Than Known Detoxifying Compounds
Let’s talk briefly about sulforaphane compared to other antioxidants and other compounds. I mentioned earlier that many researchers have come to believe that sulforaphane is one of the most potent natural compounds that we know of for preventing and reversing disease. There are a lot of popular compounds like curcumin, resveratrol, silymarin, or milk thistle that show pretty incredible effects in petri dishes, but have some significant challenges when they’re used clinically in real human beings. And this often comes down to bioavailability. For example, less than 1 percent of resveratrol and silymarin, and about 1 percent of native curcumin is bioavailable, which means that we can absorb and utilize it effectively. Now there are ways to increase the bioavailability of these substances and supplement manufacturers over the years; in some cases, I’ve done a pretty good job of this. And I do think that some of these compounds can still be useful for this reason. Particularly, I don’t use resveratrol much, but we do use curcumin and silymarin quite often therapeutically in the clinic. So they definitely have a role to play.
However, when you compare their bioavailability with sulforaphane, which is 80 percent bioavailable, it’s not even in the same ballpark. If you put this another way, in its native form or stabilized form, sulforaphane is over 80 times more bioavailable than resveratrol, silymarin, or milk thistle and curcumin in their native forms. This is a huge advantage of sulforaphane over other nutritional compounds that have at least some similar effects, like fighting inflammation and helping with detoxification.
Okay, still with me? It’s a lot of science, but again, I think understanding these mechanisms is the only way to really grok why sulforaphane has so much promise. And it’s also necessary for understanding the best ways to get more sulforaphane in your body, which is what we’re going to focus on now.
How to Incorporate Sulforaphane into Your Diet
There are two primary ways of increasing sulforaphane levels. One is consuming broccoli sprouts and the other is taking supplements. What about just eating cruciferous vegetables like broccoli or cabbage? As you know, I’m a huge believer in getting nutrients from food whenever possible, and that’s always my default recommendation. But in the case of sulforaphane, it’s a little bit tricky. One problem with this is that crucifers contain significant amounts of epithiospecifier protein, or ESP, which inhibits the activity of myrosinase. If you recall, myrosinase is the enzyme required to convert the sulforaphane precursors in crucifers like broccoli to sulforaphane itself. This means that consuming cruciferous vegetables is not a reliable source, unfortunately, of sulforaphane. Another issue with relying on just eating crucifers is that cooking has been shown to destroy myrosinase. For example, one study showed that as little as three minutes of steaming will destroy myrosinase entirely. Another study showed that five minutes of microwaving results in about a 75 percent loss of glucosinolates, which are the sulforaphane precursors, whereas pressure cooking leads to about a 35 percent loss and boiling leads to a 55 percent loss.
Finally, even storage of broccoli in the open air as would occur during transport and in retail store environments or at a farmers market, let’s say, leads to a 55 percent loss of glucosinolates after just three days after harvest. And storage in plastic bags results in a similar loss over a period of seven days. So, for all these reasons, unfortunately, again, eating cruciferous vegetables like broccoli, cabbage, etc., whether they’re cooked or raw, is not a good strategy for increasing sulforaphane in the body. Now, this doesn’t mean that cruciferous vegetables don’t have tons of other benefits. I still recommend eating them. But it does mean that we can’t depend on them for getting enough sulforaphane to be therapeutic or to have a significant effect. So that leaves sprouting and supplementation as the only other methods, and each has pros and cons. Let’s talk about sprouting first.
Most of the studies done on the benefits of sulforaphane at Johns Hopkins and elsewhere have been done with broccoli sprouts. Broccoli sprouts contain glucosinolates, the sulforaphane precursors like glucoraphanin and glucoerucin. Then myrosinase, which can be produced by chewing or cutting, maybe blending the sprouts in a smoothie, let’s say, or sometimes by the bacteria in the gut, then converts these glucosinolates to sulforaphane and erucin, which is another beneficial isothiocyanate compound. Erucin has not been as widely studied as sulforaphane, but some evidence already suggests that it might have similar benefits. One of the primary advantages of consuming broccoli sprouts as a source of sulforaphane is that they have much higher bioavailability than virtually all sulforaphane supplements on the market, with maybe one or two exceptions, which I’ll come back to a little bit later.
For example, in one study, researchers fed 12 subjects fresh broccoli sprouts and sulforaphane supplements and measured sulforaphane levels in their blood and urine. And they found that the bioavailability of sulforaphane and erucin is dramatically lower when subjects consume broccoli supplements compared to fresh broccoli sprouts. More specifically, the sprouts produce sulforaphane concentrations that were seven times higher, and erucin concentrations that were 12 times higher than the supplement did. Another similar study found that only 19 percent of sulforaphane was recovered after consuming a broccoli supplement, versus 74 percent recovery after consuming broccoli sprouts. So broccoli sprouts are definitely a better option than virtually all sulforaphane supplements on the market. However, there are a few challenges to consider with broccoli sprouts. First, the glucoraphanin content in broccoli seeds can vary quite dramatically. And testing has shown that some broccoli seeds contain no glucoraphanin at all. And at this point, companies that sell seeds are not required to certify the levels of glucoraphanin that are found in their seeds. This makes it impossible for you as a consumer or as a clinician, or practitioner, if you are one, to know whether the time and energy you invest in sprouting broccoli seeds or recommending to your patients or clients to sprout broccoli seeds will lead to any of the benefits that we’re talking about here.
Another caution with seeds is to make sure they haven’t been treated with pesticides or herbicides. The irony is pretty rich here, right? You’re sprouting broccoli seeds to get sulforaphane, which in part you’re taking to mitigate the harms of glyphosate, which is an herbicide. So buying organic seeds to sprout is really important. Second, sprouting is pretty time- and energy-intensive, and you have to follow the right procedure. The first concern is safety. The [U.S. Food and Drug Administration] warns that very young, very old, and immunocompromised people should avoid consuming sprouts. And this is because sprouts like raw milk and raw shellfish are a potential source of foodborne illness. Now, this doesn’t mean that you shouldn’t consume them. Life isn’t risk-free, and when foods like this are properly handled, the risk is very small. I’ve written about that in the context of raw milk in the past; I drink or at least some people in my family drink raw milk, and I’m not worried about that because I’m confident in the source. But there is a risk, and you should be aware of that. In the case of broccoli sprouts, the way to minimize that is to sanitize the seeds at the start of the process. And Dr. Jed Fahey who’s an expert in sulforaphane and broccoli sprouting uses a 1:10 solution of bleach to water in order to sanitize the seeds. He bleaches the seeds with that solution for 10 minutes, and then he rinses them extensively to get rid of any bleach residue. And you can do this by either filling and emptying the jar 20 to 30 times or just by continually rinsing the seeds in a colander for two to three minutes after you pour off the bleach.
Now, I can hear some of you thinking, “Bleach? Isn’t the point of this to reduce the impact of toxic exposure, and why am I putting bleach on my broccoli seeds?” That’s a reasonable question. I’m also one of the people that is reluctant to use bleach. Others have suggested things like grapefruit seed extract, hydrogen peroxide, or apple cider vinegar as potentially less toxic alternatives to bleach. But the problem with those other substances is there isn’t much research showing that they kill the pathogens, that in this case with sprouting, that can cause foodborne illness. And that’s why experts like Dr. Jed Fahey continue to use and recommend bleach.
Another key requirement is that you rinse and drain your seeds at least three times a day. So that can be maybe once in the morning, once midday, and another time at night. And for folks that work at home, this won’t be an issue, or maybe it won’t be; it depends on how much time you have, I guess. But for people who work outside of the home, it can definitely be a deal breaker or a challenge to making broccoli sprouts. You also need to make sure you have the right materials like a mason jar with a permeable lid and, even better, a lid that has little feet on it so you can invert the container and allow for better air circulation. It’s important to allow light to hit the seeds, so you need to use a clear container like a mason jar rather than an opaque container. And all this stuff can be ordered online [from] Amazon. There are also specific online sprouting stores that have all this stuff. So if you’re willing to take all these steps and put the time in, sprouting can make sense. But what troubles me is that even with all that work, the seeds you’re sprouting may not have much, or even any, glucoraphanin, which means you won’t get any sulforaphane out of them. To me, this is the biggest issue that I have with sprouting, and it’s why I’m not doing it myself. I’m not aware of a good workaround outside of sending the seeds to a research lab to be tested. And I hope that in the near future, companies that sell broccoli seeds may certify how much glucoraphanin they contain, and in my mind that will make sprouting a much more attractive option if you have the time and energy to put into it.
If you do choose this route, how much should you eat? Well, you could easily consume a couple [of] ounces a day to get really good benefit, but that’s going to involve a lot of sprouting. For reference, if you go out and buy a clamshell container of sprouts at the grocery store, that’s about four ounces. Eating two ounces of sprouts today is quite a lot of sprouts. You can put them in salads or smoothies or just eat them straight. In some of the studies on sulforaphane, the researchers actually processed the sprouts into a beverage and asked people to drink the beverage because they felt that was more feasible than asking people to eat two to four ounces of sprouts every day. So there’s no right or wrong answer there. The answer might be as much as you can tolerate and as much as you’re able to make in a sustainable way.
Step-by-Step Tutorial on How to Make Broccoli Sprouts
Before we move on to supplements, let me break all of that down into a step-by-step tutorial on how to make broccoli sprouts. Step one would be, set aside anywhere from four to six tablespoons of broccoli seeds, [and] go through and remove any foreign stuff you might see in there like rocks or twigs, etc. Put the seeds in the container that you’re going to use for sprouting, like a mason jar. Step two would be to fill that jar with water and whatever you’re using to sterilize the seeds, like the 1:10 bleach [to] water solution [that] Dr. Jed Fahey recommends or apple cider vinegar or whatever other stuff you’re using. Let that sit for at least 10 minutes. Then rinse, change, which I would say especially if you’re using bleach, you’ve got to rinse really, really thoroughly. So change the water in the jar at least 20 times or put the seeds in a colander and rinse that continually for at least two to three minutes.
Step three would be to cover the seeds with at least an inch of fresh water above the seeds and soak for at least eight hours. And then step four is the more ongoing step. So you drain the water and you add fresh water, and then rinse the seeds a couple of times. And you can do that three times a day. So maybe you do it right when you wake up. Maybe you do it again after lunch, and then you do it again before you go to bed. And after three to five days, your sprouts will be ready. Different people have different preferences in terms of when, how long they let them go. Some people prefer consuming them earlier after three days; some people prefer waiting a little bit longer. Again, [there’s] no right or wrong answer; that’s a basic time frame.
Supplementing with Sulforaphane
Let’’ move on to supplements. As I mentioned earlier, the problem here is that the vast majority of supplements on the market don’t have any sulforaphane in them at all. They contain sulforaphane precursors, like sulforaphane glucosinolate, which requires the enzyme myrosinase to be converted into sulforaphane. While some people do have gut flora that produce myrosinase, others don’t. And even when they do, the conversion is really inefficient. As we talked about, it ranges from 1 to 40 percent, but the average is only 5 to 10 percent. And that’s not enough to induce Nrf2, which is the primary mechanism for sulforaphane’s benefits. Now, some companies put myrosinase into the supplement capsule, along with the sulforaphane precursors. And these products will say something like “with myrosinase” on the label. The idea is that by putting myrosinase in the capsule, it will convert the precursors into active sulforaphane. But this doesn’t appear to work very well. Two clinical trials that used the supplement with myrosinase in the capsule failed to show benefits despite sulforaphane’s well-established effects for the conditions that were being studied.
It’s not completely clear why this is the case, but one possibility is that myrosinase gets digested by the stomach acid and doesn’t stick around long enough to convert the precursors into sulforaphane. So these pretty big problems eliminate virtually all broccoli and so-called sulforaphane supplements from my consideration. They just won’t be effective. And if you recall, this is exactly what the study we reviewed earlier showed. They compared a popular broccoli sulforaphane supplement with broccoli sprouts, and found that the broccoli sprouts contained seven-fold higher levels of sulforaphane and 12-fold higher levels of erucin, that other beneficial isothiocyanate. This might make it sound like sulforaphane supplements are hopeless, but that’s not the case. At the time of this recording, there are two supplements on the market that contain stabilized sulforaphane rather than sulforaphane precursors. The first is called Broq Band the second is called BrocElite. Both of these will be much more effective than other supplements on the market that only contain sulforaphane precursors, but of the two, BrocElite is the one I take myself and the one I recommend to my patients.
Broq uses chemical solvents to extract sulforaphane from broccoli seed. While they do have more sulforaphane in the capsule than broccoli, 10 milligrams versus 5 [milligrams], their product does not contain any of the other beneficial isothiocyanates like erucin. All of the Johns Hopkins research on sulforaphane uses broccoli sprout beverages made, tested, and ingested on the same day. In those beverages, there are numerous isothiocyanates and not just sulforaphane. Studies have shown that erucin and another isothiocyanate called (eberron? 24:36) comprise up to 25 percent of the glucosinolate content of broccoli, with sulforaphane comprising the other 75 percent. Researchers recently discovered that erucin and sulforaphane are interconvertible, which suggests that the clinical effects observed in studies using broccoli spout beverages are likely to be due to the combined effects of all isothiocyanates, not just sulforaphane. Broccoli uses a natural water extraction process, which extracts all of the isothiocyanates from the broccoli seed. This makes taking broccoli the closest you can get to the effects of consuming the broccoli sprout beverages that have been used in the vast majority of sulforaphane studies. But in fact, I think taking broccoli is significantly better than consuming broccoli sprouts.
Setting aside the inconvenience of having to make the sprouts and the issues with sterilizing them, the elephant in the room is that you never know if the broccoli seeds you’re buying actually contain glucoraphanin, and that’s whether you’ll get any sulforaphane when you sprout the seeds or what dose you’ll get if you do. Another reason I like BrocElite is that they add another isothiocyanate to the capsule called phenyl isothiocyanate, or PEITC for short. I honestly think this podcast is going to win the award for acronyms. PEITC is not found in broccoli; it’s found in watercress, and it’s a sort of chemical cousin to sulforaphane. Research suggests that it has a synergistic effect. When it’s combined with sulforaphane, it yields a 30 percent greater activation of Nrf2 than sulforaphane alone.
So let me summarize why I have chosen BrocElite to get the benefits of sulforaphane not only over other supplements, but over making broccoli sprouts. And keep in mind this is coming from a guy who has historically made his own bone broth, sauerkraut, kefir, beet kvass, and many other medicinal foods at home. I don’t shy away from that kind of work. In fact, I actually enjoy it even though I’ve had less time for it lately than I would like to have. So first, BrocElite contains a consistent, reliable amount of sulforaphane, which unfortunately, you cannot get from sprouting, at least at the time of this recording because of the unknown glucoraphanin content in broccoli seeds. Second, BrocElite also contains the other isothiocyanates that you get by consuming the broccoli sprout beverages used in sulforaphane research. And keep in mind that in that research setting, they’re able to test the seeds for glucoraphanin contents. So of course, they know that those seeds that they’re sprouting are going to lead to measurable amounts of sulforaphane. We don’t have that benefit outside of a research setting. Third, BrocElite uses a natural water-based extraction process rather than harsh chemical solvents. If I’m taking something to improve detox capacity and mitigate my exposure to toxins, I want it to be as non-toxic as possible. It just makes sense. Fourth, BrocElite adds PEITC, which works synergistically with sulforaphane to boost Nrf2 induction. Remember, this is the compound from watercress, and Nrf2 induction, as you now know, is the primary mechanism behind sulforaphane’s benefits.
Fifth, it’s frankly way easier and more convenient to get a therapeutic dose from taking BrocElite than it is from making broccoli sprouts, even if you could be sure of the sulforaphane content of the sprouts, which we can’t be. Two capsules of BrocElite contain 10 milligrams of sulforaphane, which is equivalent to drinking about three ounces of fresh juice made from broccoli sprouts harvested on the third day every day. Consuming that much sprout juice would take an enormous amount of work, and at least for me at this point in my life, I just don’t have that kind of time. And sixth, BrocElite’s a clean product. It doesn’t have any fillers in it, it’s 100 percent glyphosate residue free and non-GMO, and it’s gluten, soy, and dairy free. I’ve been in touch with the folks at BrocElite, and they’ve offered a special deal for you, my listeners and blog readers. I’ll come back to that in a moment. But first, I want to give you some tips on how to take it and a few more details on what to expect.
As I mentioned earlier, sulforaphane has a number of benefits. It promotes immune function, blocks inflammation, supports detoxification, especially the all-important phase two, which is critical because most detox supplements like vitamin C and glutathione mostly support phase one. It protects and restores brain function. Many people, myself included, notice a significant boost in mental clarity from taking BrocElite. It protects against oxidative stress, which is a component of almost all chronic diseases and also of the aging process. It has antiviral and antibacterial effects, and it protects against glyphosate exposure by inducing Nrf2 and activating NQO1, which is a phase two enzyme essential in the metabolism of a number of toxins, oxidized nutrients, and other metabolites.
So, with this in mind, I find myself recommending sulforaphane in general and BrocElite in particular most often to my patients [who] are concerned about the impact of glyphosate and other toxins on their health, who have an inflammatory or autoimmune condition like arthritis, [irritable bowel syndrome], Hashimoto’s [disease], fibromyalgia, overweight, obesity, high blood sugar, etc., insulin resistance, [or] have any kind of chronic inflammation or pain. This could even be just like a local back injury or chronic kind of injury that flares up. It tends to work really well in those conditions. Anyone who’s had cancer, has a family history of cancer, or who just wants to be proactive in lowering their risk of cancer, people with brain fog, memory problems, difficulty with word recall, or other cognitive issues, people with any kind of depression, anxiety, and even more serious mental illnesses. We talked about sulforaphane’s impact even on schizophrenia. People with neurodegenerative conditions like dementia, Alzheimer’s [disease], Parkinson’s [disease], epilepsy, etc. And if you recall, this goes back to sulforaphane’s ability to boost BDNF levels. And then finally, [for] kids or adults with [attention-deficit/hyperactivity disorder], autism spectrum disorders, or other behavioral disorders, there [are] some really, really interesting [studies] about sulforaphane and autism in particular.
So are there any contraindications with sulforaphane and BrocElite? Not that I’m aware of at this point. I do have a few patients that are sensitive to sulfur-based compounds in general, like glutathione or [methylsulfonylmethane], and folks with that issue may want to start with maybe one capsule or half [a] capsule and see how they do and then build up to the full dose. But that’s pretty rare. Otherwise, in more than 2,000 studies, sulforaphane has been safe and well-tolerated at the typical doses found in broccoli sprouts and supplements. I suggest a dose of two capsules per day taken at breakfast. And [there are two] reasons [why] I say breakfast. One, it’s generally better to take it with food. In about 10 to 20 percent of people, it will cause mild gastrointestinal discomfort if they take it on an empty stomach. And that’s been more true in my patients with [small intestinal bacterial overgrowth] or other [gastrointestinal] issues. The second reason I suggest taking it [at] breakfast is that because of how it upregulates BDNF levels, it can really increase mental clarity and focus and have all these amazing benefits. But I’ve found in some of my patients, if you take it right before bed, it can actually interfere with getting to sleep because there’s so much activity; there’s so much going on in the brain. So that can easily be avoided by taking it at breakfast, instead of at dinner, instead of before bed.
Now you can definitely get a benefit from taking a smaller dose like one capsule a day. That’s still like drinking one and a half ounces of fresh broccoli sprout juice a day, which certainly will be helpful. So while two [capsules] a day provides a more therapeutic dose, if money’s tight or you can only tolerate one capsule a day, let’s say you’re sensitive to sulfur compounds, it’s totally still worth it. Most people will notice the effects within two days to two weeks. Interestingly, the first effect that many people notice is vivid dreams, and I suspect that’s due to the upregulation of BDNF, which improves brain function. The other main effect that people tend to notice right away is some reduction of chronic inflammation or pain. And that will also tend to improve over time as Nrf2 becomes more active. BrocElite can be stored in a cool, dry place. It doesn’t need to be refrigerated if you take it regularly. But if you are storing it for longer periods, you should put it in the fridge.
If you want to give BrocElite a try, head over to Kresser.co/BrocElite, and they’re offering a 27 percent discount on your first order, which means you’re saving about $37 on a three-month supply and also getting free shipping. Also, in the next few weeks, I’m going to be doing a free webinar with some of the science team from BrocElite, so you can ask them any questions you might have about sulforaphane, detoxification, and how to get the most out of the supplement. Make sure you’re on my email list at ChrisKresser.com to get notified about that.
Whew, that was a monster episode. I have such a broad audience. Some of you are laypeople with no science background, and others are scientists, researchers, and physicians. I did my best to find a balance between making this material accessible and not dumbing it down. Send us an email or a message on Instagram, Twitter, or Facebook to let me know how it went. Along with the glyphosate episode, these are the first two solo episodes I’ve done in a long time. And as I mentioned recently, you’ve heard about the survey; we’re experimenting with some new formats and I would definitely love to hear your feedback. All right, that’s it for today. Again, if you want to try out BrocElite, go to Kresser.co/BrocElite, and you can get 27 percent off your first order. And if you missed the glyphosate podcast, make sure to check that out. I think that sulforaphane is the most potent nutritional compound we have access to for mitigating the potential harms of glyphosate along with other environmental toxins that we’re increasingly exposed to. If you want to see the references for this show, as with any other show, check out the show notes on my website. And then keep sending your questions into ChrisKresser.com/podcastquestion, and I’ll talk to you next time.