Brussels sprouts are the vegetable that millions of people around the world love to hate. The butt of innumerable jokes, Brussels sprouts emit a flatulence-like odour when they are overcooked – so don't overcook them!  Cooked until tender, rather than sulfurous, Brussels sprouts have a unique, sweet mildly cabbage-y flavour that goes with many favourite foods.

What Are the Key Nutritional Benefits of Brussels Sprouts?

Brussels sprouts aren't just members of the Cabbage Family. These leafy green vegetables are actually little cabbages that grow on a stalk. Like all the other related cabbages, Brussels sprouts are a good source of the following:

Carotenoids, plant chemicals related to beta-carotene, which the body can convert into vitamin A as needed.

Glucosinolates, such as glucobrassicin, which becomes indole-3 carbinol (I3C), gluconasturtiian, which becomes phenethyl-isothiocyanate (PEITC) glucoraphanin, and sinigrin, which becomes allyl-isothiocyanate (AITC), which becomes sulforaphane (SFN). All of these chemicals help to protect against cancer in small doses, but act as goitrogens, interfering with the thyroid's ability to absorb iodine and make thyroid hormone, in high doses. Getting just enough of these plant chemicals is the key.

Sulfur: That stinky sulfur is actually an essential nutrient. Many of the liver's detoxifying enzymes can only be made with it. The enzymes that break up mucus are made with sulfur. Eating Brussels sprouts provides an important raw material for detoxification; a process the body can accomplish all on its own as long as it gets the sulfur it needs.

In fact, Brussels sprouts support both of the key phases of detoxification. Their vitamin C content contributes to the formation of Phase I enzymes, which break down toxic compounds into smaller chemicals. Their sulfur compounds support the formation of Phase II enzymes, which attach these smaller compounds to other chemicals that make them inert, or chemically inactive. However, it's always possible to get too much of a good thing, but eating cooked (but not overcooked!) Brussels sprouts several times a week is inherently healthy. Because of the goitrogens, raw or pickled Brussels sprouts should only be consumed as an occasional food, eaten no more often than once a week.

What Health Issues Are Especially Responsive to Brussels Sprouts?

There are over 500 studies confirming the value of Brussels sprouts in preventing certain types of cancer. Various investigations have concluded that in addition to the raw materials for detoxification enzymes mentioned above, spouts also have additional health benefits:

Chlorophyllin from green Brussels sprouts helps reduce the toxicity of aflatoxin, a toxin made by molds that live on grain.

3,3′-Diindolylmethane (DIM) in Brussels sprouts reduces the proliferation and migration of certain kinds of breast cancer cells.

Sulforaphane (SFN) [1-isothiocyanato-4-(methylsulfinyl)butane] in Brussels sprouts and broccoli raab, activates a process of cellular suicide in lung cancer cells.

Brussels sprouts can be useful in binding cholesterol. The liver flushes out excess cholesterol by attaching it to bile salts that it sends to the gallbladder, and then on to the colon. When these bile salts interact with certain fibres in Brussels sprouts, they stay in the colon and get flushed down the toilet with the stool, rather than recirculating back into the bloodstream. Cooking Brussels sprouts increases the potency of these fibers, although raw sprouts also have this property. One study showed that eating Brussels sprouts on a regular basis could lower cholesterol levels as much as 27%. This is not, despite what Brussels sprouts enthusiasts may tell you, more than the cholesterol lowering attained from statin drugs. Therefore, and because of goitrogens, it's best to treat Brussels sprouts as a supplemental cholesterol-lowering food, rather than one you eat every day.

There is also evidence that one of the sulfurophanes in Brussels sprouts counteracts an enzyme that transforms baby fat cells into fully formed and functional fat cells, giving dieters a fighting chance against weight gain.

The thing to keep in mind about all these potentially wonderful nutritional benefits to be had from the consumption of Brussels sprouts is that they come at a price. The chemicals that fight cancer and weight gain also interfere with thyroid function. Laboratory studies with animals have found that the effects of cruciferous vegetables on the thyroid are minimal or undetectable when all Cabbage-family vegetables are kept to about 2.5% of the total diet. That allows for about one serving of raw Cabbage-family vegetables per day, or maybe two if cooked, but certainly no more. Fortunately, there is no need to eat multiple portions of any particular vegetable, since maximum benefits are achieved with just one serving a day, or maybe even just one or two per week.

Where Do Brussels Sprouts Fit in the Families of Vegetables?

As mentioned earlier, Brussels sprouts don't just look like little cabbages, they actually are little cabbages. Brussels sprouts, collard greens, cabbage, cauliflower, and kale, all belong to the same plant species, Brassica oleracea. In the broader plant family there are radishes, horseradish, land cress, water cress, mustard (both the greens and the seed used to make the condiment), daikon, arugula, turnips, rutabagas, and canola. Like most members of the Crucifer family (plants with four petals arranged in a cross), Brussels sprouts contain sugars that are concentrated by frost or by dry cooking methods. In general, Brussels sprouts and other edible plants of the Crucifer-family are tastier when combined with onion, garlic, black pepper, sweet peppers, olive oil, or lemon juice.

What Is the Best Way to Eat Brussels Sprouts Raw?

The best way to eat Brussels sprouts raw is “only occasionally.” This is because Brussels sprouts contain glucosinolates, and glucosinolates interfere with the thyroid's ability to make thyrotrophic hormone, and thyroxine and tri-iodothyronine are needed for normal thyroid function. Because the glucosinolates appear in both raw and cooked Brussels sprouts, some nutrition commentators have assumed that eating any kind of Brussels sprouts interferes with the thyroid, but in truth, cooked Brussels sprouts don't cause this problem. The offending chemicals have to convert into their harmful form by an enzyme called myrosinase. This enzyme is broken down by boiling, baking, roasting, or stir-frying the sprouts. If you prefer your sprouts raw, just don't eat them, or any other cabbage-family vegetable, more often than three times a week.

Any interesting way to prepare raw Brussels sprouts is as kimchi. (See the recipe under ‘Cabbage'.) Just use Brussels sprouts instead of Napa cabbage.

What Is the Best Way to Eat Brussels Sprouts in Salads?

Shaved Brussels sprouts mixed with diced green apples and Pecorino cheese, dressed with honey vinaigrette and served with salt and pepper, makes an interesting salad. Brussels sprouts also mix well with other kinds of sprouts, such as Brocco sprouts. The flavours of raw Brussels sprouts are compatible with chicken, walnuts, and Parmesan. Shredded Brussels sprouts also blend well with crumbled bacon, toasted almonds, shallots, and Pecorino-Romano cheese, served with a lemon or orange vinaigrette.

What Is the Best Way to Cook Brussels Sprouts?

Brussels sprouts are traditionally cooked by boiling, but this method leaches out potassium and other useful plant chemicals. Sprouts are tastier when they are steamed, pan-fried, or roasted with salt and black pepper and olive. Many cooks cut off the bottom of the sprout and then cut the sprout in half. They then toss the halved sprouts into boiling water for a few minutes (about 4 minutes on average) just until the still-green leaves begin to separate. Then they cook the leaves of the sprouts in bacon until tender. Onion, garlic, red pepper flakes, and a little fresh lemon juice bring out the wonderful flavours.

What Are Some Ways to Make Brussels Sprout Juice More Interesting?

When making Brussels sprout juice, choose vegetables that have no wilted or yellow leaves. Wash them thoroughly before juicing, and use a twin-gear juicer. Note that a ‘centrifuge juicer' just doesn't have the power to process more than about 1/4 cup (50-60 ml) of Brussels sprout juice at a time.

Most people need to mix their Brussels sprouts with apple and/or carrot to make the juice more palatable. The nutritional value of the juice actually increases when other fruits and vegetables are added, so don't be afraid to make a juice you actually like to drink.

How Do I Get Kids to Like Brussels Sprouts?

Most kids don't like Brussels sprouts, but most kids do like bacon. So combining Brussels sprouts with bacon makes them far more ‘kid-friendly'. If your family doesn't eat pork, pan-fry Brussels sprouts in butter and serve with lemon juice, pepper, and salt. Make sure you cook the sprouts just long enough so that they are tender and the outer leaves retain their appealing green colour.

How Long Do Brussels Sprouts Keep?

In much of northern Europe, Brussels sprouts are the only fresh vegetable served after January the first. This is because most other vegetables have had to be pickled or salted, or have just gone rotten by this time. Brussels sprouts will keep for up to three months in the crisper, provided they are in a mesh bag and kept separated from other vegetables that spoil more quickly.

Tips for Frugal Use of Brussels Sprouts

While Brussels sprouts may keep in the crisper for weeks or even months, if you do need to store them for more than 10 days, their flavour will be better when they are frozen. Blanch the sprouts in boiling water for five minutes to bring out their green colour. As soon as they are ready, shock the blanched sprouts in ice water to stop further cooking. Finally, drain the sprouts, and then put them into plastic bags and freeze. It's better to use frozen sprouts during the first month, but they will keep for as long as six months if you need them to.

References

Choi Y, Um SJ, Park T. Indole-3-carbinol directly targets SIRT1 to inhibit adipocyte differentiation. Int J Obes (Lond). 2013 Jun; 37(6): 881-4. PMID: 22986685.

de Groot AP, Willems MI, de Vos RH. Effects of high levels of brussels sprouts in the diet of rats. Food Chem Toxicol. 1991 Dec; 29(12): 829-37.

Gross-Steinmeyer K, Eaton DL. Dietary modulation of the biotransformation and genotoxicity of aflatoxin B(1). Toxicology. 2012 Sep 28; 299(2-3): 69-79. doi: 10.1016/j.tox.2012.05.016. Epub 2012 May 26. Review. PMID: 22640941.

Kalpana Deepa Priya D, Gayathri R, Gunassekaran GR, Murugan S, Sakthisekaran D. Apoptotic role of natural isothiocyanate from broccoli (Brassica oleracea italica) in experimental chemical lung carcinogenesis. Pharm Biol. 2013 May; 51(5): 621-8. doi: 10.3109/13880209.2012.761242. Epub 2013 Feb 4.

McMillan M, Spinks EA, Fenwick GR. Preliminary observations on the effect of dietary brussels sprouts on thyroid function. Hum Toxicol. 1986 Jan; 5(1): 15-9.

Nicastro HL, Firestone GL, Bjeldanes LF. 3,3′-Diindolylmethane rapidly and selectively inhibits hepatocyte growth factor/c-Met signaling in breast cancer cells.J Nutr Biochem. 2013 Aug 19. doi: pii: S0955-2863(13)00099-5. 10.1016/j.jnutbio.2013.05.004. [Epub ahead of print].