I Tested 5 Sulforaphane Supplements. Here's the One I Kept.
I'm not a doctor. I'm not a scientist. I ran the front desk at a dental practice for 19 years, and I'm the person in my family who reads the back of every box at the grocery store. They tease me about it.
I started sulforaphane after hearing about it on a podcast. I wanted the good of broccoli sprouts without eating a bowl of them every morning. And I liked the idea of supporting my body's own defences against what we all take in without meaning to.
Over about a year and a half I went through four brands.
The first bottle gave me a stomach I didn't recognise. The second was a big tablet I dreaded every morning, and the price went up twice. The third I took for three months and felt nothing. I wasn't even sure what dose I was taking. The fourth changed its look halfway through the year.
So I did what I do at the grocery store. I lined every bottle up on the kitchen table and read the labels. What I found changed how I think about the whole thing.
Sulforaphane didn't fail you. You never got a real dose of it.
What I checked
Here's what I didn't know when I started. Broccoli sprouts don't really contain much sulforaphane sitting there ready to go. They contain glucoraphanin, the raw material. Your body gets sulforaphane when glucoraphanin meets an enzyme called myrosinase. No enzyme, and you're relying on whatever your gut bacteria manage to convert.
So a lot of labels sell you the raw material, or an extract weight, or a big number on the front that isn't on the back. Once I understood that, three checks sorted all five bottles.
- Is sulforaphane stated in mg, on its own line of the supplement facts panel? Not a percentage. Not a number on the front of the bottle. A line on the back that says sulforaphane and a number of milligrams.
- Is myrosinase included? The enzyme that turns glucoraphanin into sulforaphane.
- Is it free of black pepper, wasabi and maltodextrin? Pepper and wasabi are the two ingredients reviewers blamed most for stomach trouble. Maltodextrin is a filler people keep finding on the back of bottles they thought were clean.
I also scored each one on what it's like to take every day and what it costs per day.
The rankings
Rejoin Daily Defense
Sulforaphane in milligrams, on its own line. The only bottle that passed all three checks.
| Sulforaphane | 16 mg per capsule, on its own panel line. 32 mg a day at 2 capsules |
|---|---|
| Glucoraphanin | 51 mg per capsule |
| Myrosinase | 35 mg per capsule, included |
| Other ingredients | The acid-resistant capsule (hypromellose and pectin). That's it |
| Black pepper / wasabi / maltodextrin | None of the three |
| How I take it | 2 a day (32 mg), so a 60-capsule bottle lasts me 30 days |
| Price | From $0.66 a day on the Buy 2 Get 1 FREE bundle |
| Guarantee | 90-day money-back |
Why it's my #1
When I turned this bottle around, the first thing I saw was the word I'd been hunting for on every other label: sulforaphane, 16 mg, on its own line. Not a percentage I had to work out with a calculator. Just the number.
Right above it are the other two lines I'd learned to look for: glucoraphanin, 51 mg, and myrosinase, 35 mg. So it isn't only the sulforaphane already made. It also brings the raw material and the enzyme that makes more.
Then I read the other ingredients. It's the capsule. That's the whole list. No black pepper. No wasabi. No maltodextrin. No fillers I had to look up. After four bottles of reading the small print, it was the shortest label on my table.
I take 2 a day, 32 mg, so a bottle lasts me 30 days. After a bottle where I was only getting half of what I thought I was paying for, knowing my daily amount mattered to me.
What it's like to take
Two capsules with breakfast. Capsules, not a pressed tablet. The thing I noticed most was what wasn't there. I'm not going to promise you'll feel something by Tuesday. Sulforaphane doesn't work like that, and nobody honest will tell you it does. What I can tell you is that for the first time I know exactly what I'm taking every morning.
Stated dose 10 · Enzyme 10 · Clean label 10 · Daily experience 9.0 · Value 9.2
What I liked
- Sulforaphane stated in mg on its own panel line: 16 mg a capsule, 32 mg a day
- Glucoraphanin and myrosinase both listed, with amounts
- Other ingredients are the capsule and nothing else
- No black pepper, no wasabi, no maltodextrin
- I take 2 a day, 32 mg, so a bottle lasts me 30 days
- $0.66 a day on Buy 2 Get 1 FREE, with 90 days to decide
The honest downsides
- Two capsules a day, not one
- Online only. You won't find it at the pharmacy
- Newer brand. It doesn't have the years of Amazon reviews the big names have
Bottom line: every other bottle on my table asked me to trust a percentage, a front-label number or a line that wasn't there. This is the one that just told me. It's the one I kept.
Check today's price at Rejoin →Buy 2 Get 1 FREE, $58.95 · 90-day money-back guarantee
Quick comparison
Swipe the table sideways to see all five →
| Rejoin Daily Defense | Avmacol Extra Strength | SMNutrition (Smoky Mountain) | Andrew Lessman Cruciferous | Nutricost SGS | |
|---|---|---|---|---|---|
| Check 1: sulforaphane in mg on its own line | ✓ 16 mg a capsule | ✗ Not stated | ✗ No. The "50MG" is front-label only | ✗ No. Glucosinolate figure only | ✗ No. 0.5% of a 50 mg extract |
| Check 2: myrosinase | ✓ 35 mg | ✓ Yes | ✓ Yes | ✗ Not listed | ✗ Not listed |
| Check 3: no pepper, wasabi, maltodextrin | ✓ None | ✗ Maltodextrin | ✗ Black pepper | ✗ Wasabi | ✗ Maltodextrin |
| Checks passed | 3 of 3 | 1 of 3 | 1 of 3 | 0 of 3 | 0 of 3 |
| Format / per day | 2 capsules | 1 tablet | 2 capsules | 1 capsule | 1 capsule |
| Price | $32.95 subscribe, $37.95 one-time (60 caps) | $65.99 (75 tablets) | $49.95 (60 caps) | $89.90 (360 caps) | $18.95 (120 caps) |
| Cost per day | $1.10 subscribe, $1.27 one-time, $0.66 on Buy 2 Get 1 | $0.88 | $1.67 | $0.25 | $0.16 |
| Cost per mg of stated sulforaphane | About 3.4¢ subscribe, about 4¢ one-time, about 2¢ on Buy 2 Get 1 | Not stated | Not stated as a total | Not stated | About 63¢ |
| My score | 9.6 | 6.5 | 6.1 | 5.2 | 4.3 |
How I worked out the cost per mg: Rejoin, $32.95 subscribe ÷ 960 mg in a bottle (32 mg × 30 days) = about 3.4¢, $37.95 one-time ÷ 960 mg = about 4¢, or $58.95 ÷ 2,880 mg across three bottles = about 2¢. Nutricost, $18.95 ÷ 120 capsules = about 16¢ a capsule, and each capsule works out to about 0.25 mg of sulforaphane (0.5% of 50 mg), so about 63¢ per mg. Avmacol, Smoky Mountain and Lessman don't state a total sulforaphane amount on the panel, so there's nothing honest to divide by. Competitor prices are Amazon list prices when I checked in September 2026. Rejoin shows both its one-time and subscribe prices.
Skip ahead to the one I kept →
Avmacol Extra Strength
The one with the research reputation. But the label never tells you how much sulforaphane you're getting.
| Sulforaphane | Not stated. Sold as "sulforaphane-producing" |
|---|---|
| Glucoraphanin | At least 35 mg a tablet, inside a 480 mg proprietary blend |
| Myrosinase | Yes, from moringa leaf and mustard seed |
| Other ingredients | Microcrystalline cellulose, maltodextrin, silicon dioxide, modified cellulose gum, magnesium stearate |
| Serving / price | 1 tablet a day · 75 tablets · $65.99 · about $0.88 a day |
My take
If you've read anything about sulforaphane, you've heard of Avmacol. It's the brand people mention on podcasts, and it's the one I'd pick if Rejoin didn't exist. It does check 2 properly: the enzyme is in there.
But the label doesn't state a sulforaphane amount at all. It's "sulforaphane-producing". You get at least 35 mg of glucoraphanin in a blend, and the rest depends on how well it converts in you. There's no number on the panel to check.
Then there's the back. Maltodextrin is the second "other ingredient", and there are three more fillers after it. That's the one that sent a lot of reviewers back to the box.
"Contains Maltodextrin which spikes blood sugar."— Amazon reviewer
And it's a pressed tablet. Several reviewers found it hard to swallow. I was one of them.
Stated dose 4.0 · Enzyme 9.5 · Clean label 5.0 · Daily experience 6.5 · Value 7.5
Liked: a well-known name, myrosinase included, one a day. Held back: no stated sulforaphane mg, maltodextrin and four more fillers, a big tablet.
SMNutrition (Smoky Mountain) Sulforaphane
The "50MG" is on the front of the bottle. It isn't a line on the back.
| Sulforaphane | "50MG" on the front and in the listing. Not a line on the panel. The panel's only sulforaphane line is 100 mg of extract at 0.4%, which works out to about 0.4 mg |
|---|---|
| Glucoraphanin | 260 mg of seed extract at 13%, which works out to about 33.8 mg |
| Myrosinase | Yes, as a sprout extract with myrosinase enzyme (150 mg) |
| Also in it | Black pepper fruit extract (BioPerine) 10 mg, mustard seed powder 50 mg |
| Serving / price | 2 capsules a day · 60 capsules = 30 days · $49.95 · about $1.67 a day |
My take
This one has the enzyme and a real amount of glucoraphanin, so it's a serious formula. But the 50 mg that sold me isn't on the supplement facts panel. When I did the maths on the one line that does say sulforaphane, 0.4% of 100 mg, it works out to about 0.4 mg. The rest depends on conversion, and the label doesn't say how much.
The serving caught me out too. The panel says 2 capsules. The brand's own website says 1 capsule in one place. I read the front, took one a day, and was only getting half of what I thought I was paying for. I wasn't the only one.
"It states 50 MG Sulforaphane, that's in two pills not one."— Amazon reviewer
Then there's the black pepper. It's there to help absorption, but pepper was the ingredient reviewers blamed most when their stomachs complained. At two capsules a day, it's also the most expensive per day on my list.
Stated dose 4.5 · Enzyme 9.0 · Clean label 5.5 · Daily experience 6.0 · Value 5.5
Liked: myrosinase included, real glucoraphanin amount, capsule not tablet. Held back: the 50 mg isn't a panel line, black pepper, 2-a-day vs 1-a-day confusion, $1.67 a day.
Andrew Lessman Cruciferous Extracts
The cleanest "other ingredients" line after Rejoin. But the broccoli dose is under 1 mg, and there's wasabi.
| Sulforaphane | Not stated. 80 mg of broccoli extract standardized to 1.2% sulforaphane glucosinolate, which works out to about 0.96 mg of glucosinolate |
|---|---|
| Myrosinase | Not listed |
| Also in it | Wasabi root extract 20 mg, mustard seed 40 mg, red cabbage, Brussels sprouts, kale, vitamin C |
| Other ingredients | A natural plant cellulose capsule, nothing else |
| Serving / price | 1 capsule a day · 360 capsules · $89.90 · about $0.25 a day |
My take
I wanted to like this one. The other ingredients line is only the capsule, same as Rejoin. It's a mix of six cruciferous vegetables, which sounds lovely.
But it's a veg mix, not a sulforaphane supplement. The broccoli part works out to under 1 mg of sulforaphane glucosinolate, which is the raw material, not sulforaphane itself. And no myrosinase is listed. The Amazon panel shows 8 mg of total glucosinolates across all six vegetables. The brand's site says 6 mg. I couldn't tell which label is current.
Then there's the wasabi, 20 mg of it. Wasabi was the other ingredient people named when their stomach turned.
One reviewer's experience:
"Gave me horrible pains, gas, and upset stomach."— Amazon reviewer
Stated dose 2.0 · Enzyme 3.0 · Clean label 7.5 · Daily experience 6.5 · Value 7.0
Liked: capsule-only other ingredients, low daily cost, a year's supply in one bottle. Held back: wasabi, no myrosinase listed, under 1 mg of glucosinolate from broccoli.
Nutricost Sulforaphane Glucosinolate
The cheapest bottle on the table. Also the smallest dose.
| Sulforaphane | Not stated in mg. 50 mg of broccoli seed extract at 0.5% sulforaphane, which works out to about 0.25 mg a capsule |
|---|---|
| Myrosinase | Not listed |
| Other ingredients | Rice flour, hypromellose capsule, magnesium stearate, maltodextrin |
| Serving / price | 1 capsule a day · 120 capsules · $18.95 · about $0.16 a day |
My take
At 16 cents a day, this looks like the smart buy. The front says "50MG" in big letters. Under it, in small print, it says that's the broccoli seed extract, not the sulforaphane.
Do the maths from the back: 0.5% of 50 mg works out to about 0.25 mg of sulforaphane a capsule. To match the 32 mg I get from two Rejoin capsules, you'd need 128 of these a day. That's more than the whole 120-capsule bottle. So the cheapest per day is the most expensive per mg on my list, about 63 cents per mg.
There's no myrosinase either, and maltodextrin is on the back.
"without myrosinase in the formula, it’s basically broccoli extract with no engine under the hood."— Amazon reviewer
Stated dose 1.5 · Enzyme 2.0 · Clean label 4.5 · Daily experience 7.0 · Value 6.5
Liked: lowest price per day, one a day, easy to find. Held back: about 0.25 mg of sulforaphane, no myrosinase, maltodextrin, "50MG" is the extract.
Frequently asked questions
What's the difference between sulforaphane and glucoraphanin?
Glucoraphanin is the raw material in broccoli sprouts. Sulforaphane is what you get when glucoraphanin meets the enzyme myrosinase. A label that only lists glucoraphanin, or a "glucosinolate", is telling you about the raw material, not the finished compound.
Why does myrosinase matter?
It's the enzyme that does the converting. Without it, you're relying on your gut bacteria to do the job, and that varies a lot from person to person.
Why did my old bottle upset my stomach?
I can't tell you for sure. What I can tell you is that black pepper and wasabi were the two ingredients reviewers blamed most. Rejoin has neither. Its other ingredients are the capsule and nothing else.
How many Rejoin capsules do you take?
I take 2 a day, 32 mg, so a bottle lasts me 30 days.
How long before I notice anything?
I won't promise you'll feel it on a timetable. That's why the 90-day money-back guarantee matters: it gives you three bottles' worth of time to decide.
What if it's not for me?
Rejoin has a 90-day money-back guarantee.
My verdict
I spent a year and a half thinking sulforaphane just wasn't for me. Upset stomach, a tablet I dreaded, three months of nothing, a label that kept changing. I nearly gave up on the whole idea.
It turned out the problem wasn't sulforaphane. It was that I'd never actually been given a clear dose of it. Missing sulforaphane lines, percentages, front-of-bottle numbers, the enzyme left out, pepper or wasabi or maltodextrin added in. Once I read the backs, the choice made itself.
If you've never taken sulforaphane: start with the one that tells you what's in it.
If you've tried it and felt nothing: check your old label for a sulforaphane line in mg. I'd bet it isn't there.
If your last bottle upset your stomach: look for pepper and wasabi on the back. Rejoin has neither.
Rejoin Daily Defense
16 mg of sulforaphane a capsule, on its own line. Myrosinase included. Nothing else but the capsule.
Subscribe and save prices shown. 90-day money-back guarantee.
Check today's price at Rejoin →