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. Hi Mark,

    I’m suffering from sulfur breath. i have been looking for remedy for a long time now to no avail. After reading your comments on the goodness of sulfur I’m so lost, i want to get rid of the bad breath caused by sulfur rich foods. please help me.

    Thanks Koyo

    koyo wrote on February 23rd, 2013
  2. My parents ate all garlicky foods, so I and m brother ate garlic too and loved it. When I close my eyes, I can smell the bread toast with crushed garlic or langos with crushed garlic. Or garlic soup …

    Jan Rendek wrote on April 19th, 2013
  3. Not sure if this has been mentioned, but a way to eat onions raw (even white onions) is to chop/slice them up, then soak them in a bowl of cold water for half an hour. I’m not sure if this gets rid of much of the nutrition, though!

    Marianne wrote on October 2nd, 2013
  4. Before I was not really curious with the help of Sulphur to our body, I don’t like to eat those Sulphur rich food until the time I my hair falls a lot each day my body seems like very stressed. It really makes me worry until my friend told me to learn to eat more protein and sulphur rich food. Now i feel a lot better and feels my body cope with those minerals in my body. with the help also of the sulphur supplement that he give to me.

    Its a great reading..

    Sophia wrote on October 6th, 2013
  5. Good stuff!!! One thing to consider for the people that feel sick, get headaches, rashes etc. when eating heavy sulfur foods is that they may have a CBS enzyme gene mutation, and so have issues processing sulfur or may be insufficient in molybdenum.

    Matt wrote on October 13th, 2013
  6. Brussel sprouts are the best, try shredding them with a food processor, and dress them with some nice vinegary dressing, serve them raw with red onions and sliced carrots, add a few sliced almonds and some craisins or diced apricots, yummmmm… if you want to cook them, use everything except the dressing and saute them lightly in olive oil and chopped garlic, then add everything else, I make them like that for the holidays, very festive looking with the craisins… also yummmmm…

    Benny Long wrote on October 16th, 2013
  7. I have a question. From where do the vegetables get their sulfur so that we can eat it. Is it in the soil?

    Ara wrote on November 15th, 2013
  8. I love to hear about the different ways to prepare veggies.
    If you really want to protect yourself and your family stop using the microwave to radiate your food. That oven is a killer.

    Hollis wrote on November 21st, 2013
  9. I make (raw) sauerkraut from red cabbage, red onions, garlic sea salt and eat 2 TBS or more with every non-sweet meal. Works great tossed in salads–eliminates need for dressing.

    Sarolta Green wrote on January 17th, 2014
  10. I like thinly sllced cabbage with vinegar and oil, salt and pepper. Makes a delicious salad especially after it’s wilted a little.
    But my favorite use of cabbage is to combine it with sauerkraut. I saute some onions, and when they are translucent, add cabbage. When it’s fairly well cooked, but not too limp, add sauerkraut. I usually rinse it once. But as I’m heating it, and it does not seem sour enough, I add some more without rinsing it. I eat it warm or cold out of the refrigerator. You can cook up enough for a few days,

    Joanie wrote on October 29th, 2014
  11. great write, thankful to have found you, blessed be be blessed <3

    Sarah O'Plenty wrote on November 27th, 2014
  12. 40% of the population has CBS and/or BHMT genetic mutations and should be careful about the amount of sulphur consumed and the impact on their methylazation cycle. One size does not fit all for nutrition, if you feel bad, have gas or headache or weight gain, consider genetic testing to confirm as sulphur is everywhere, healthy foods, many meds, and topical solutions.

    Monica wrote on December 13th, 2014
  13. Omg! No wonder I like these vegetables so much! My body may be crying out for more sulfur rich food. I really love Asparagus! Fill a stove top frying pan with them and then put in about a pint of water and half stick of butter. Put on med low heat for like 10-15 mins with a top and then 5-10 mins with no top until all water has evaporated away and you are left with tender plump buttery asparagus. Throw on salt and pepper and you’ll almost be in heaven eating that. Thanks for info

    kyle ford wrote on February 20th, 2015
  14. I love the more pungent garlic and onion types of vegetables. You have heard of someone eating so many various they turn orange? I eat so much of garlic and onion relatives that you can smell it in my skin on the palms of my hands and yet it may have been days since I last handled prepared the sulfur-rich goodies. You can also detect it in my blood whenever I may have drawn some on accident. I can’t go without garlic and onions for even just one day, I try and consume some whenever am cooking something that could go with it.

    Barbara wrote on November 17th, 2015

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