What Are the Key Nutritional Benefits of Brussels Sprouts?
Brussels sprouts aren't just members of the Cabbage Family. They actually are little cabbages that grow on a stalk. Like all the other related cabbages, Brussels sprouts are a good source of:
• 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 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 sulfur. The enzymes that break up mucus are made with sulfur. Eating Brussels sprouts provides an important raw material for detoxification 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. It's always possible to get too much of a good thing, of course, 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 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 kinds of cancer. Various investigations have concluded that in addition to the raw materials for detoxification enzymes mentioned above:
• 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 fibers in Brussels sprouts, they stay in the colon and are 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%--which is not, despite what Brussels sprouts enthusiasts may tell you, more than the cholesterol lowering from statin drugs—but it's best to treat Brussels sprouts as a supplemental cholesterol-lowering food, rather than one you eat every day, because of goitrogens.
And 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 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 if all Cabbage Family vegetables are kept to about 2.5% of the total diet. That allows for maybe one serving of raw Cabbage Family vegetables per day or maybe two if cooked, but no more. Fortunately, there is no need to eat more and more and more of any particular vegetable, since maximum benefits are achieved with just one serving a day—or maybe even just one or two a 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 are the same plant species, Brassica oleracea. In the broader plant family are also 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, Brussels sprouts contain sugars that are concentrated by frost or by dry cooking methods, and like most members of the Crucifer family, Brussels sprouts 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.” Because Brussels sprouts contain glucosinolates and glucosinolates interfere with the thyroid's ability to make thyrotrophic hormone, thyroxine and tri-iodothyronine needed for normal thyroid function, and 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. Actually, cooked Brussels sprouts don't cause this problem. The offending chemicals have to converted 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 3 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 a honey vinaigrette and served with salt and pepper makes an interesting salad. Brussels sprouts also mix well with other kinds of sprouts, such as broccosprouts. The flavors of raw Brussels sprouts are compatible with chicken, walnuts, and Parmesan, and 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. These sprouts are tastier when they are pan-fried, roasted with salt and black pepper and olive, or steamed. 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) until the still-green leaves start 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 flavors.
What Are Some Ways to Make Brussels Sprout Juice More Interesting?
When making Brussels sprout juice, choose sprouts that have no wilted or yellow leaves. Wash them thoroughly before juicing, and use a twin-gear juicer. 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 will need to mix their Brussels sprouts with apple and/or carrot to make the juice 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. Most kids do like bacon. 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, cooking the sprouts just long enough so that they are tender, but the outer leaves are still an appealing green.
How Long Do Brussels Sprouts Keep?
In much of northern Europe, Brussels sprouts are the only fresh vegetable served after the First of January, because most other vegetables have had to be pickled or salted or have gone bad. Brussels sprouts keep for up to 3 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 keep in the crisper for weeks or months, if you need to store them for more than 10 days, their flavor will be better if they are frozen. Blanch the sprouts in boiling water for 5 minutes, bringing out their green color, but then shock the blanched sprouts in ice water to stop cooking. Drain them sprouts, and then place them in 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.
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].