Marks Daily Apple
Serving up health and fitness insights (daily, of course) with a side of irreverence.
7 Feb

Why You Should Eat Sulfur-Rich Vegetables

“Be sure to eat your sulfur.”

When’s the last time someone told you that? Except for the Wahls talk, probably never. My mother certainly didn’t.

Few people even know much about sulfur besides the whole rotten egg, fire and brimstone thing. It’s a mineral with a role in our physiology, but it doesn’t showboat like the obscenely corporeal calcium, forming bones and teeth that you can literally feel and see. It won’t immediately soothe your restless muscles or put you right to sleep, like magnesium. Unlike zinc, it doesn’t figure prominently in the production of a sexy hormone like testosterone. And though you can take iodine and get an instant reaction from your thyroid, taking sulfur doesn’t produce anything tangible. In short, sulfur lurks in the background and keeps a low profile.

So why does Terry Wahls promote the consumption of three cups of sulfur-rich vegetables every day?

Before we get to that, let’s define what we’re discussing here. What exactly qualifies as a sulfur-rich vegetable? Any and all fibrous non-leafy (although some have leaves, they’re never the culinary focus) usually-green vegetables that steam well and emit a distinctive, offensive-to-some odor probably contain considerable amounts of sulfur and can be called “sulfur-rich”:

  • Brassicas – cabbage, broccoli, cauliflower, Brussels sprouts, bok choy, and related vegetables.
  • Alliums – onions, shallots, garlic, leeks.
  • Lots of edible stalks, lovely smells if you cook it wrong, and a tendency to go well with lemon butter. That sort of thing.

Back to Wahls’ recommendation to eat more sulfur. What’s the justification for it?

Well, by weight, sulfur is one of the most abundant mineral elements in the human body, coming in at around 140 grams for the average person. And as any regular reader of this blog should know, you don’t get to be an abundant mineral in human physiology by accident. Nope: sulfur is involved in hundreds of physiological processes. Let’s explore some of the big ones:

Sulfur is required for the synthesis of glutathione, one of our premier endogenous antioxidants. I’ve talked a bit about glutathione before. It’s one of the good ones.

Sulfur, in the form of disulfide bonds, provides strength and resiliency to hair, feathers, and feathered hair.

Sulfur is required for taurine synthesis. Taurine is essential for proper functioning of the cardiovascular system, our muscles, and the central nervous system.

Sulfur binds the two chains of amino acids that form insulin. It may seem like we bag on insulin a lot, but it’s absolutely necessary for life.

Sulfur is found in methionine, an essential amino acid (think meat, eggs, cheese), and in cysteine, a “non-essential” amino acid (think pork, poultry, eggs, milk).

But wait a minute. If sulfur can be found in all the animal foods we’re already eating – beef, chicken, eggs, pork, dairy – what’s the point of eating all those sulfur-rich vegetables?

There are two reasons, I think, for focusing on “sulfur-rich” vegetables. First, it’s helpful to group things. We’ve got the leafy greens, we’ve got the brightly colored produce (more on this next week), and we’ve got the sulfurs. We want to eat things from all three categories, and making the latter a separate group ensures that we won’t “overdose” on spinach. It’s just a neat, slick way to get the pro-vegetable message across and increase variety of intake. Second, and most importantly, sulfur-rich vegetation tends to come with extremely potent organosulfur compounds that offer a lot of benefit to those who eat them. Animal sources may contain plenty of sulfur-rich amino acids, which we undoubtedly require, but they don’t contain the organosulfur compounds.

Let’s explore them and go over a few of their potential benefits.

Alliums and Their Allyl Sulfur Compounds

Garlic, onions, shallots, and leeks all contain various organosulfur compounds, some of which show major potential.

Garlic-derived organosulfur compounds have shown promise as anti-cancer operatives in in vitro studies.

Various garlic sulfides protected mice from peroxidative damage and increased glutathione activity in the liver. The garlic sulfides were delivered via corn oil, but I would recommend garlic butter if you’re looking for a fatty vessel.

When cooking meat, using an onion and garlic-based marinade reduced the formation of heterocyclic amines (a carcinogenic compound).

Onion-derived sulfur compounds improved the glucose tolerance of diabetic rats (but garlic-derived compounds did not).

Brassicas and Their Various Organosulfur Compounds

Sulforaphane, an organosulfur compound found in broccoli (especially the sprouts), cabbage, brussel sprouts, and cauliflower, inhibited mitochondrial permeability and reduced oxidative stress by increasing glutathione activity in rats.

In inhabitants of a Chinese farming community, where airborne pollution is high and liver cancer incidence is elevated, drinking a sulforaphane-rich broccoli sprout drink was also able to increase the urinary excretion of those airborne pollutants.

Broccoli sprouts reduced oxidative stress in type 2 diabetics, as shown in a double blind placebo-controlled trial.

Organosulfur compounds from all kinds of brassicas have the potential to reduce or counteract the carcinogens derived from high-heat cooking.

Eating brassicas along with a carcinogen salad prevented the absorption of said carcinogens.

How to Prepare These Vegetables (and Preserve Their Compounds)

You can’t just go eat a head of cabbage like an apple, or throw together a lovely salad of raw onion, raw garlic, and raw broccoli stalks. I mean, you could, but it’d be pretty unpleasant. No, you want to cook these vegetables, because they taste better and are likely more nutritious that way. But you also don’t want to miss out on all the delightful organosulfur compounds we’ve been discussing. You want the optimal prep method – or close to it.

Onions and Garlic

If it’s beneficial allyl sulfur compounds you want to consume, eating your alliums raw and sliced is the ticket. Heat breaks down the compounds. The only problem is that those same allyl sulfur compounds that might fight cancer, boost antioxidant status, and ward off liver damage are the very things that make raw onion and garlic so pungent and unpalatable. Some people enjoy the stuff raw – not me, besides a little chopped garlic in my salad dressings and some raw onion on a salad – but most prefer them cooked. Luckily, studies suggest that by slicing your alliums and letting them sit for at least ten minutes before cooking, you allow the myrosinase enzyme to release more allyl sulfur compounds and make them more resistant to heat.


Steaming is the way to go. One study found that lightly steaming broccoli rendered the sulforaphane three times more bioavailable than after heavily cooking it. I like to steam my broccoli until it’s bright green and tender enough to pierce the stalk with a fork with an emphatic push. Soggy, dull green broccoli is the worst – and it’s not nearly as beneficial. One group of scientists corroborate my method, saying that three to four minutes of light steaming – until “tough-tender” – is ideal.


Again, research confirms that lightly steamed cabbage offers more bioavailable organosulfur compounds than cabbage cooked at high heat in the microwave. Chop it up to your desired consistency. Let sit for a few minutes so the myrosinase gets to work. Stick to four or five minutes of steaming. Then, toss with your fat of choice. If you want to microwave, use the low or medium setting.


Cut into small florets, let sit for ten minutes (to let the myrosinase enzyme do its work and make the glucosinates more available), and steam or bake. I’m a big fan of baked cauliflower tossed with turmeric, curry powder, cayenne, salt, and olive oil.

Brussels Sprouts

Although I’m sure the “best” way to cook sprouts (like all the other brassicas) is to quarter and steam them for five minutes, I can’t help but think you’re missing out on the perfect opportunity for some prime caramelization in the oven. So yeah, I’ll steam Brussels sprouts and toss with butter or olive oil and enjoy them just fine, but every once in awhile I’ll finish those suckers off in the oven on high.

Everything Else

Slicing, sitting, and steaming is always a safe bet.

For all these foods, try to embrace the bitterness. Love the bite, because that bite and that bitterness means you’re getting those interesting compounds. Enjoy the crispness of lightly cooked brassicas from time to time. It may take some getting used to, and you might have to play with different flavor combinations so that the bitterness will work, but you’ll be pleasantly surprised. Avoid the mush.

As I mentioned in the greens post, three cups a day are probably unnecessary. Just try a bunch from the ones I’ve listed, see what you like, and try to get some sort of sulfur-rich vegetable into your mouth at least a few times a week. Or, go all out and give the three cups a day routine a shot. You might really like it and thrive on it.

What’s your favorite sulfur-rich vegetable? How do you eat it? Let me know in the comment section!

You want comments? We got comments:

Imagine you’re George Clooney. Take a moment to admire your grooming and wit. Okay, now imagine someone walks up to you and asks, “What’s your name?” You say, “I’m George Clooney.” Or maybe you say, “I’m the Clooninator!” You don’t say “I’m George of George Clooney Sells Movies Blog” and you certainly don’t say, “I’m Clooney Weight Loss Plan”. So while spam is technically meat, it ain’t anywhere near Primal. Please nickname yourself something your friends would call you.

  1. I have heard that broccoli sprouts are many times more ‘nutritious’ than broccoli itself. Does that include the sulfur component? Broccoli sprouts on my salad are a nice way to up my servings.

    Honora Carroll wrote on February 7th, 2012
  2. I love alllllll of those yummy sulfur-rific veggies! Onions and garlic are pantry staples, and broccoli, cauliflower, brussel sprouts are eaten several times a week, along with kale, chard, bok choi…..yummmm!!!!!

    Karen wrote on February 7th, 2012
  3. That baked cauliflower dish sounds great! buying some this weekend!

    PaleoDentist wrote on February 7th, 2012
  4. I’m really glad you’re going over all this Wahls stuff. Her video wasn’t enough! I need more!!

    Jess wrote on February 7th, 2012
  5. I juice broccoli stems, kale, parsley, and add some aloe juice. you get used to the taste.

    rik wrote on February 7th, 2012
  6. I eat a lot of all the vegetables mention, both raw and cooked.. I am also allergic to sulfur drugs. Is there any connection between the sulfur drugs and the sulfur rich vegetables?

    Carl wrote on February 7th, 2012
    • Sulfa and sulfur are not the same and you can eat them even if allergic to sulfa drugs. You can even take MSM.

      There is a good article by a doc online about this issue. Sorry I don’t have link – just google MSM and sulfa allergy.

      deenpac wrote on February 15th, 2012
  7. Hi Mark, great post! I just watched Terry Wald’s video the other day, so this was very interesting for me.

    One question…during the challenge this year, one participant from Spain I believe sent in a video recipe for a tuna dish that called for garlic. He said to remove the green part (or the part that looks like the root in the middle of the clove) to avoid having the smell linger on your breath the rest of the day. This has worked wonderfully for me…with a little parsley, you’d never know I’d had garlic (or at least my boyfriend says so! lol). I have tried this with onions too…cutting out the center part…and it appears to have a similar effect….

    So, am I losing all or most of the benefits of these vegetables by cutting out the part that leads to lingering bad-breath?


    primalpal wrote on February 7th, 2012
    • May be a myth, but I was always told that those parts were the most nutritious. I always mince the center/root area very fine – since its the strongest smelling/tasting.

      rarebird wrote on February 7th, 2012
  8. Garlic and onions are used in virtually all South Asian dishes. However, they are cooked for a long time until they are broken down and turn into a sauce. Though they become much more digestable, I wonder if there are any useful compounds left in them.

    Sabrina wrote on February 7th, 2012
  9. Brussel spouts, chopped up fine, sautéed with onions and garlic, salt and pepper, and CUMIN! Oh my sweet Lord…SO! GOOD! I could eat the whole pan.

    I think I have, actually.

    I slept alone after that, lemme tell ya! LOL

    pat wrote on February 7th, 2012
  10. I love raw garlic and onions, raw garlic is good with fresh french bread,onions I usually chop them and put little salt and let them sit for 10 min. and give quick squize ,put some lemmon and olive oil add some avacodo ,tomatoes and enjoy with freshly baked bread.Does asparagus included in that weg list,because after eating asparagus my your urune smells for day or so.

    lisa hartley wrote on February 7th, 2012
  11. Try sautéed cauliflower in beef tallow, with some simple s&p, and garlic.


    pat wrote on February 7th, 2012

    Uh, no.

    pat wrote on February 7th, 2012
  13. Gotta wait a few months for the leeks. She just planted them… the winter wonders.

    kem wrote on February 7th, 2012
  14. I love those little brussels sprouts! Just quarter them, mix with a little olive oil, and pepper, and roast in the oven at 400 for 20 mins….yummy!

    Jan wrote on February 7th, 2012
  15. These types of vegetables are even harder for me to eat than tthe leafy greens; that “bite” it vicious! But my favorite would have to be broccoli or cauliflower :)

    M wrote on February 7th, 2012
  16. Brocolli with butter and a little sea salt. Perfect.

    wayne wrote on February 8th, 2012
  17. Great article, but i am a little surprised at the recommendation for microwaving.

    Dave uk wrote on February 8th, 2012
  18. Has anyone tried Cabbage Bolognese or Cabbage Lasagne? They are both delicious! Make up your usual bolognese sauce and serve on a bed of shredded steamed cabbage instead of pasta. Likewise, cabbage leaves alternating with layers of meat sauce, topped with torn buffalo mozzarella and cooked in the oven is better than the usual version. We always use cabbage in place of all pastas.

    Judi Strega wrote on February 8th, 2012
  19. Ive been thinking about making sauerkraut out of kale. I reckon the culture might turn the K1 into K2 the way Cow’s stomachs do. Does anyone want to weigh in on this?

    Also, I haven’t made any form of sauerkraut before so I’m not sure whether it would work (have enough moisture etc).

    SophieE wrote on February 8th, 2012
  20. This is great news for this garlic lover :) I use garlic in the kitchen just about every night. Onions seem to be becoming a regular staple as well. Yum!

    Alessandra wrote on February 8th, 2012
  21. After watching Terry Wahl’s video, my wife started taking MSM. She has autoimmune disease (hasn’t been given a name, but is Behcet’s-like) which has had her wheelchair-bound at times this past year, and in considerable pain the rest of the time, despite high-dose prednisolone and azathioprine.

    Over the weekend, she realised that she was essentially pain-free. We’re somewhat skeptical, as there could be confounding factors (she’s had a stinking cold, so perhaps her immune system is “busy” *goes all hand-wavy*) but we’re cautiously optimistic.

    Joe Wrigley wrote on February 8th, 2012
  22. Your version of baked cauliflower sounds good, but try tossing cauliflower with turmeric and black pepper, layer onto a baking sheet, and then cover with bacon. Bake it around 350/375 (Fahrenheit) and when the bacon is done, the cauliflower is amazing.

    Brian wrote on February 8th, 2012
  23. I normally won’t eat any of these nasty veggies! I eat nasty smelling Kimche which is made from garlic, cabbage, and onions and fermented for several months in the ground.
    I eat this to piss my witch off evey time she cuts raw onions in the house. Does this mean I’m eating right for this article?

    WW Rutland wrote on February 8th, 2012
  24. Garlic and onions for me. Raw and cooked. Amazing things.

    Doug Brunell wrote on February 8th, 2012
  25. I make this every Sunday and eat it throughout the week with meals or alone as a snack with a harbored egg.

    Food Processor Shedder attachement:
    1 Green Cabage
    1 Red Cabbage
    3 stalks celery
    3 carrots
    7 or 8 radishes
    1 or 2 jalapeños (remove some seeds)
    2 cloves of minced garlic
    2 Bubbies Pickles (or any fermented pickle)
    Juice of one lemon
    sea salt and pepper
    good quality balsamic vinegar (about half cup)
    Apple Cider Vinegar with the mother (about half cup)
    good quality Olive Oil (about half a cup
    Mix well and cover in Fridge
    will stay good all week! Will make your reflux disappear and make your food digest easily and help recovery after workouts – always eat with a protein.

    Jim wrote on February 8th, 2012
    • Oooops, “hardboiled” egg that is!

      Jim wrote on February 8th, 2012
  26. soar throat or just sick: chopped garlic on a spoon covered in honey – RAW. Defintelly pulled me through college on a budget that couldn’t afford medecine. Now I do it still, though I’m the only one… can’t get others to try it out.

    Florence wrote on February 8th, 2012
  27. The only way I’ve ever been able to eat brussels sprouts is to run them through the food processor with slicer attachment and then sauteing in bacon grease.

    It’s weird because broccoli has always been my favorite vegetable – I prefer to buy frozen florets and then lightly cook them in the microwave. Add butter and salt to taste and I’m in heaven.

    Shayne wrote on February 8th, 2012
  28. Where does lacto-fermenting fit in with this. Would making sauerkraut out of the veggies maintain the nutrient integrity as much as raw or would it damage them?

    Josh wrote on February 8th, 2012
  29. yes these foods are all very high in MSM, shame the author did not mention this as the alternate supplement name for organic sulfur – can be easily added to your diet as i have done for 10 years and it has saved my life, cured all allergies and never had a cold for 10 years. Would not live without sulfur – go MSM!

    brad waddell wrote on February 9th, 2012
  30. I LOVE cabbage spinach and kale sauteed lightly in coconut oil! :) with some onions usually too.
    And i love red onion on my salads.

    Thanks mark for all this information!

    Emily wrote on February 13th, 2012
  31. I’ve been taking a garlic supplement every night. Thoughts?

    Ashley wrote on February 15th, 2012
  32. Oh my…these are what I refer to as “rich” veggies…

    Summer’s raw broccoli stems are delish sliced thin in salads;

    Cabbage/Brussels Sprouts/Cauliflower…raw in salads or sauteed quickly with olive oil or organic bacon drippings and garlic…

    Andrea wrote on February 15th, 2012
  33. Just a suggestion on kale, we’ve never been fans but I started putting it on the mini chopper and grinding it fine. I add it to salads, omelets, soups, salsa, etc. It blends in perfectly !
    Also, if you let veggies sit in vinegar for a spell it “cooks” them making the nutrients more bio-available.

    Gem wrote on February 16th, 2012

Leave a Reply

If you'd like to add an avatar to all of your comments click here!

© 2016 Mark's Daily Apple

Subscribe to the Newsletter and Get a Free Copy
of Mark Sisson's Fitness eBook and more!