Broccoli is probably the vegetable which has suffered the most from cliché cultural representations of healthy eating over the now 70+ years of mass media driven society. However, clichés are not 100 percent detrimental constructions. Like myths and stereotypes, they do have their usefulness. In this particular case, it underlines the part that vegetables play in healthy eating, a declared purpose of many individuals in consumer societies.
In this article, we will go beyond the stereotype and offer an in-depth analysis of broccoli, with a particular focus on its far-reaching health benefits. We will start with a casual description and a few fun facts about broccoli to whet everyone’s appetite; then we will follow that up with a detailed nutritional examination of the vegetable. This will be done for both raw broccoli and cooked broccoli for those of you who are especially interested in seeing how the cooking process can alter the nutritional make-up of a vegetable.
The main course will consist of discussing broccoli’s most important and acknowledged health benefits, from protection against cancer to skin rejuvenation. Then, we will round matters up with hints on preparing broccoli in a healthy way so that it retains most if not all of its remarkable properties.
Broccoli – General Facts and Figures
Hailing from the cabbage family, also known to the public as the cruciferous vegetable type, or the Brassicaceae family if one cares to be more scientific, broccoli is most closely related to cauliflower. Indeed, considering the fact that they both originated in the Mediterranean area more than 2000 years ago, it would not be wild speculation to assume they probably were different results of the same breeding experiments, though farmers of the time would not have considered their activity as such.
Broccoli was first systematically planted in the Italian Peninsula during the times of the Roman Empire and has maintained its place as a staple of Italian cuisine ever since. In fact, the name derives from the Latin word designating arm, resembling broccoli’s unique appearance. Naturally, over the years, there has been much horticultural experimentation with different varieties, however, nowadays the most popular variant is known as Calabrese, a variant that is moderately green, named after the region in Italy where it supposedly originated, Calabria.
In the United States, broccoli consumption was at first limited to the rather small Italian-American community. The surge in immigration from Italy at the end of the 19th century and beginning of the 20th, translated into a surge in the popularity of broccoli, which started becoming a dietary staple in earnest in the 1920’s.
The recent discovery that plants from the Brassicaceae family (particularly cauliflower and Brussels sprouts, and of course broccoli) can enrich the diet with significant amounts of sulforaphane, a phytonutrient with anti-cancer properties, added to the already considerable regard in which the American consumer held broccoli.
Broccoli is a vegetable that thrives in moderately cool climates. That is why, when considering the Northern Hemisphere, it is usually planted in late summer, and harvested in late November to early December and even later. The process proper starts much earlier, in late spring to early summer, when the broccoli seeds are planted which will become the seedlings that are transplanted into the ground. The plant can withstand temperatures as low as -6 °C (21 °F); however, anything constantly hotter than 26 °C (80 °F) can spell disaster for it. Broccoli thrives under daylight temperatures of between 13 °C (55 °F) and 22 °C (70 °F). It takes about 10 weeks from the transplantation of seedlings until the harvesting of broccoli can begin.
The problem with growing broccoli is not the climate, but the fact that it can be the target of many pests. Caterpillars – caterpillars of cabbage white butterfly the cabbage looper caterpillar – can ruin the crop if they are not dealt with before eating the growing tips. Cabbage root maggots attack the root of the plant and are difficult to spot and then manage. Other frequently encountered problems to take into consideration are aphids, mildew, gray mold, clubroot, or bacterial soft rod.
An encouraging aspect regarding the commercialization of broccoli is that it is a vegetable that can be the least suspected of excessive pesticide use. In fact, according to a study from EWG’s Shopper’s Guide to Pesticides in Produce among the most popular fruit and vegetables, broccoli lands a respectable 33rd place out of 48 favorite items (1st being the most pesticide-prone and, naturally, 48th being the least). A commonly encountered myth is that vegetables mainly produced in China are grown using copious amounts of pesticides, yet this is one example where the myth is proved wrong. For the record, out of the 22.3 million tons of broccoli produced (2013 figures), 9.7 million tons are produced in China and 7.9 in India. The birthplace of broccoli, Italy, produces a mere 0.5 million tons a year.
If you are on the other side of the economic chain, a customer looking to buy broccoli, make sure to select plants with compact floret clusters that show no yellow spots and exhibit a uniform color. Furthermore, the plants should not have yellow flowering present, as that is a sure sign that is overmature. When opting for storing broccoli, never wash it beforehand, place it in a plastic bag attempting to remove as much air from the bag as possible. Cutting and refrigeration quickly reduce the amount of vitamin C in broccoli; therefore it is best to be cooked on the spot, or after no more than 48 hours of refrigeration, although it starts to wilt after about 10 days. One could also freeze broccoli; however, it is not a vegetable that lends itself particularly well to the process.
Broccoli Nutritional Facts Sheet (Raw vs. Cooked)
For the sake of the analysis, let us state that we are considering samples of 100 grams, in cases of raw broccoli and broccoli that has been boiled, drained and had a bit of salt added, the amount of salt being 10 percent of the daily recommended value of sodium, or about 250 mg. All of the values presented in this section bear in mind the standard value of 2000 calories per day for a healthy adult.
As general information goes, our sample of raw broccoli equates to 34 calories of energy, while the cooked batch is just a fraction higher, at 35 calories. Raw broccoli has a caloric ratio that is as close to perfection as it can be – carbohydrates represent 71%, 20% by protein and just 9% of fat. This rate does not drastically change when cooked, the only noticeable difference being that it loses a bit of protein (~ 3%) that is “redistributed” equally among fat and carbs. Broccoli is excellent when you are thinking about a diet that aims for fast weight loss and, like all cruciferous vegetables, a constant inclusion in one’s diet is of paramount importance to healthy eating.
Broccoli is more than 89 percent water, contains no cholesterol or saturated fat whatsoever; it provides 10% of the daily value of dietary fiber in the case of our 100 grams serving (13% for cooked broccoli) and more than 5% of the necessary value of protein. The sweet undertones that broccoli presents are reflected in the 2 percent of the total mass that sugars represent. When cooked, it loses more than 15% of total sugar. Nevertheless, in both cases, the glycemic load is negligible for a healthy adult as it represents less than 3% of the total daily recommended amount.
Besides the impressive input of vitamins that broccoli provides, nutritionists recommend it for the extremely low amount of fat it contains. 100 grams of raw broccoli incredibly contains only 0.4 grams of fat or about 1 percent of the daily recommended amount. The large majority of it is represented by a polyunsaturated fat, with virtually no saturated fatty acids in broccoli’s composition. The statistics surrounding the cooked broccoli sample are surprising about the beneficial omega-3 and omega-6 fatty acids – 119 mg per 100 grams (compared to 21 mg for the raw variant) and 51 mg per 100 grams (17 mg for raw broccoli), respectively.
When we get to broccoli’s vitamin input, here is where it really shines. Broccoli is well known as a proficient provider of vitamin C, with more than 89 mg (or about 150% of the daily recommended intake for an adult) to be found in 100 grams of broccoli, and in the case of cooked broccoli, we get just about the daily value for the same quantity. This statistic shows that the amount of vitamin C in vegetables (broccoli being just the prime example) can be subjected to dramatic changes, and for the maximum intake of vitamin C one should consume all veggies and fruit uncooked.
The other highlight of broccoli, arguably even more spectacular than the amount of vitamin C, is the quantity of vitamin K. 100 grams of raw broccoli contains a quantity of 102 mcg of vitamin K (or roughly 125 percent of the daily value), while the cooked variant provides the body with 175 percent of the daily recommended intake (or 141 mcg). This also shows that balance in the diet of raw and cooked vegetables is something one should strive for.
Other, less impressive, figures from the vitaminic make-up of broccoli are: considerable amounts of vitamin A (12% of the daily value for raw broccoli, 31% for the boiled one) and folate (16% of the recommended daily intake for the raw variant, 27% for cooked broccoli); decent amounts (between 5 and 10 percent of the daily value) of thiamin, riboflavin, vitamin B6, and pantothenic acid; traces (between 3 and 5 percent of the recommended quantity) of vitamin E, niacin, and choline.
Broccoli’s mineral input is along the same lines as any cruciferous vegetable – a solid source of potassium and manganese (about 10 percent of the daily value in each case), a good source of calcium, magnesium and phosphorus (approximately 5 percent of the daily recommended intake) – with the important observation that broccoli is a vegetable that is one rare source of selenium, delivering 5 percent of the daily value per 100 grams. All of these figures are true for raw broccoli, with no significant modifications in the quantities in the case of cooked broccoli.
Main Health Benefits of Broccoli
The anti-cancer effects that regular consumption of broccoli brings is acknowledged. In fact, hundreds of studies in the past decade have been dedicated to this subject. The reason for this often traveled path of research is a simple one: broccoli has anti-cancer benefits that work on a truly global scale – against chronic inflammation, against oxidative stress, and against insufficient detoxification. Let us review the positive effects broccoli can have in each of these dimensions.
In layman’s terms, an overexertion of the body’s anti-inflammatory responses equates to constantly accelerating a car while never switching out of first gear. Biochemical compounds called isothiocyanates (or ITC’s for short) perform the role of naturally neutralizing a wide variety of toxins in the metabolism and thus signaling the anti-inflammatory system that it can take a well-deserved rest. Cruciferous vegetables in general and broccoli, in particular, are a great source of the particular fiber that, when metabolized, becomes the building blocks of isothiocyanates. While this action is an absolute scientific certainty, research is still very much in its infancy concerning glucosinolates, other resultants from broccoli consumption, though speculation is strong regarding its benefits in fighting chronic inflammation.
Other trusted soldiers in the battle against inflammation are omega-3 fatty acids. More complex biochemical compounds that play important roles in signaling inflammation – PGH3 or LTE5 – derive from omega-3. Although broccoli is not an excellent source of omega-3 acids (compared to fatty vegetables), it nonetheless provides considerable amounts without the saturated fats inherent to other sources.
Allergies are a key component of chronic inflammation, though they do not always manifest themselves outwardly. When detecting the presence of an allergenic substance, the immune system produces specific antibodies called IgE-antibodies. A phytonutrient, present in broccoli and other cruciferous vegetables, named kaempferol reduces the impact of these antibodies contributing to a lesser level of inflammation overall.
As an ally to the antioxidative process, broccoli stands out among cruciferous vegetables because it has the highest concentration of vitamin C, the premiere source of antioxidant compound among all nutrients. In addition to this crucial component, broccoli also provides the body with the important flavonoids quercitin and kaempferol, which allow better assimilation of vitamin C. Other substances present in broccoli that have pronounced antioxidant effects are beta-carotene, lutein, and zeaxanthin, from the carotenoid class. Manganese, zinc, and vitamin E are also important to the process and, as we have pointed out in the previous section, are present in significant amounts in broccoli. Consuming foods which bring a considerable input of antioxidative biological compounds cannot be stressed enough as preventive measures against cancer.
The detoxification process represents the third leg of the preventive process. Though this particular mechanism has not yet been fully mapped out, isothiocyanates have been acknowledged to play a central role in detoxification. Isothiocyanates result from the biosynthesis of glucosinolates found in certain foods. Broccoli contains three variants of these important natural substances – glucobrassicin, gluconasturtiin, and glucoraphanin. Not only that, but broccoli contains such an amount as to be highly effective in aiding the body in producing sufficient amounts of isothiocyanates.
This is the technical side of things. Concretely, a diet which favors cruciferous vegetables (among which broccoli is a prime exponent) statistically lowers the incidence of common cancer types such as prostate and ovarian cancer, bladder cancer, breast cancer and colon cancer. The amount in which these vegetables should be consumed on a weekly basis differs, however, there are statistics that consider that an input of broccoli worth 22 calories, which is considerably less than 100 grams of raw broccoli, per week should provide the necessary amount of anti-inflammatory, antioxidant and detoxifying substances, in the context of a balanced diet and frequent exercise.
As we have stated earlier, Broccoli is one vegetable which is prone to lose its nutrients through overcooking dramatically. The same goes for the components which provide its anti-cancer benefits. It is recognized that steaming broccoli for up to 4 minutes is the method of cooking that works best for the purpose of preserving all the nutrients.
Healthy eating is an advantage in itself; however, broccoli has been noted to help in the improvement or maintenance of the following conditions:
- Arthritis – sulforaphane, a substance which is present in small amounts in raw broccoli but increases exponentially when broccoli is steamed or boiled, has been acknowledged to delay the onset of osteoarthritis significantly.
- Cardiovascular – a recent study has shown that rats exhibiting dangerous levels of hypertension have responded favorably when administered sulforaphane. This has opened other avenues of research. The antioxidative benefits described in the section dedicated to anti-cancer benefits of broccoli also apply here. Furthermore, broccoli and cauliflower juice have been demonstrated to mildly lower cholesterol levels. Sulforaphane solidifies the walls of all blood vessels, an aspect that was particularly important to diabetics who, because of the significant damage to blood vessels, are markedly more prone to myocardial infarction and stroke than the general population. Dietary fiber and chromium (of which broccoli contains traces) help reduce blood sugar levels.
- Eye and Skin Health – sulforaphane is a compound long touted to have extraordinary qualities in the field of geriatrics, mainly in protection from ultraviolet rays. The significant levels of carotenoids such as zeaxanthin and lutein place broccoli in the same vein as carrots when it comes to diets that promote eye health.
Incorporating Broccoli in Your Diet
One aspect that should be mentioned before embarking on even the purchase of broccoli is that if you are interested in extracting the most nutrients from broccoli, then you should opt for fresh broccoli sprouts because they score far better on the nutrient scale than the mature variant. In some cases, especially the dietary fiber amount, sprouts are far more potent than the commonly sold variant of the plant. A study from Johns Hopkins University has unearthed that broccoli sprouts that are 3-days old contain as many as 20 times more nutrients than 10-day mature broccoli.
As we have previously stated, “plain-old, market-sold” broccoli is sensitive to temperature. However, it is not especially susceptible to the medium. That means that stir-frying it for a short period depletes fewer nutrients than boiling for a longer period. More nutrients were retained through frying it at 130 °C for four minutes (about 68 percent of the raw sample) than by boiling it at 120 °C – 140 °C for eight minutes. Obviously, steaming for the same period (about 5 minutes) is still the healthiest way of cooking broccoli, yet that cannot always be to everyone’s taste.
Because such an in-depth treatment of broccoli is not complete without a few recipes featuring it, we suggest broccoli-cheese chowder, green pizza, broccoli gratin with crispy onions or skinny orange chicken with broccoli. Bon Appetit!