Broccoli sprouts are the seedlings of broccoli plants and they are a powerhouse of nutrients that have all sorts of health benefits, particularly for cancer patients. And they’re also a yummy addition to your sandwiches, wraps and salads. They have a kind of earthy taste, not quite like the full grown broccoli florets, and they have a lovely satisfying crunch. They aren’t particularly easy to find in the shops but they’re much better freshly grown anyway, and hopefully I can persuade you to raise your own. It’s not difficult.

Along with all the other cruciferous vegetables, like cauliflower, broccoli, rocket (arugula), radishes and a number of others, broccoli sprouts contain an enzyme called myrosinase that’s released when they are damaged in some way, like biting them. This enzyme breaks down glucosinolates into their active forms. One group of those is isothiocyanates. Isothiocyanates in turn activate other enzymes that can break down and remove toxic chemicals that can cause disease.

Broccoli sprouts contains large amounts of a particular glucosinolate which breaks down to sulforaphane. They have up to 100 times the amount of sulforophane as mature broccoli, depending on how fresh they are, which makes them a particularly valuable source of it. Remember to chew them well to activate the myrosinase that produces sulforophane.

What does sulforophane do?

Its benefits include:

• Helping prevent and fight cancer

• Supporting strong bones

• Helping fight H. pylori infection

• Supporting a healthy heart

• Detoxifying the body

• Helping protect the brain

• Improving lung function

• Supporting MS patients

How broccoli sprouts help prevent and fight cancer

Sulforophane has been shown to work on breast, prostate, colon, lung, oral, bladder, liver,  stomach and skin cancers.

Its functions include inhibiting enzymes that can convert compounds into carcinogens, and also removing carcinogens from the body.

Sulforophane can also affect your genes. The science of epigenetics is fairly new, but genes can be switched on and off, which affects whether they do their job or not. It’s important for the right genes to be switched on and off. Sulforophane can switch off genes with mutations, such as the BRCA gene mutations, and protect against disease.

Breast cancer

In a small and fairly short trial, sulforaphane found some positive but not statistically significant changes in tumour biomarkers that are usually used to detect improvements in cancer development (1).

Cancer stem cells are crucial to the development and recurrence of breast cancer. A mouse trial found that sulforophane eliminated stem cells (2). This has profound implications for protecting against breast cancer recurrence.

Another exciting mouse trial found that if a pregnant female ate broccoli sprouts regularly, it has a protective effect against breast cancer in her infant. This works via the epigenetic effect of sulforophane mentioned above (3).

Prostate cancer

Mice with prostate cancer were fed broccoli sprouts for 16 weeks. At the end of the trial, the researchers found that their cancers showed a significant reduction in growth (4). A very small human trial of men with recurrent prostate cancer didn’t have quite such spectacular results, but their PSA results did improve. Their PSA doubling time was significantly increased too. The researchers hoped to try it again with higher doses (5).

Colon cancer

Mice given a carcinogen were then fed broccoli sprouts. Normally they would have suffered colitis leading to colon cancers, but those on the broccoli sprout diet had less colitis and tumours (6).

In a human placebo-controlled trial, they were asked to eat 20 g a day of broccoli sprouts for 2 weeks to test the effect on their gut bacteria. The researchers found that the broccoli sprouts increased certain bacteria that are known to produce butyrate, which protects the lining of the colon from cancers (7).

Lung cancer

In 2005, a trial was conducted on mice to see whether sulforaphane could reduce lung cancers caused by tobacco. The results were positive and the researchers suggested that it should be tested on smokers and ex-smokers with early stage tumours (8).

Air pollution is considered to be another risk factor for lung cancers. So a trial was conducted in a particularly polluted area of China to see whether broccoli sprouts could help to detoxify people of the carcinogens in the air. They found that the sprouts worked very quickly and consistently to remove the carcinogens from the trial participants’ bodies, showing that they could have a protective effect against air pollution (9).

Oral cancer

In a review in 2016, they looked at a mouse trial, a laboratory study and a small human trial that aimed to discover whether sulforophane could protect against oral cancers. Mice that were predisposed to oral cancers had far fewer tumours after taking sulforophane than those who didn’t. In the laboratory study, human neck and head cancer cells treated with sulforophane produced a protein that helped to detoxify carcinogens. In the human trial, healthy participants were asked to swish around their mouths fruit juice mixed with broccoli sprout extract for a few days. They produced the same protective detoxifying protein (10).

Bladder cancer

In another animal study, this time rats, who had been dosed with a carcinogen designed to cause bladder cancer, were given broccoli sprout extract and again it showed protective effects (11).

In a laboratory study more recently, the researchers found that broccoli, its sprouts or their pure isothiocyanates helped to kill bladder cancer cells by inducing apoptosis (programmed cell death) and other mechanisms. They went on to study the effects in mice implanted with human bladder cancer cells, where broccoli isothiocyanates significantly reduced the growth of tumours (12).

Liver cancer

In Qidong, a city in China, they have the highest incidence of liver cancer in the world. Part of the problem is related to moulds called aflatoxins that are found in contaminated foods such as corn, which are known to be associated with liver cancer carcinogenesis. Researchers tested an infusion (‘tea’) made from broccoli sprouts on 200 healthy adults and then measured the amount of aflatoxin in their urine. The results varied widely, as it seems that some people absorb the sulforophane more easily than others. But in the high absorber group, there was a significant level of aflatoxin excreted, suggesting that this is a good way of protecting at least some of the people in the area from liver cancer (13).

Stomach cancer

The rate of stomach cancer increases up to 6-fold in people who carry the H. pylori bacterium. It tends to cause gastritis and the resulting inflammation can lead to stomach cancer. A placebo-controlled clinical trial in Japan, where rates of H. pylori infection are particularly high, involved a group of people who were infected. They were asked to eat 100 g of broccoli sprouts each day for 2 months. The levels of H. pylori were substantially lower in the group eating the broccoli sprouts, as was the degree of gastritis. The bacteria were not completely eliminated, though. But the researchers suggested that broccoli sprouts would be a useful intervention to reduce the risk of stomach cancer (14).

Skin cancer

Hairless mice who were exposed to UV light twice a week for 20 weeks were subsequently treated topically with a concentrated broccoli sprout extract 5 times a week for 11 weeks. In the placebo group, all of the mice developed skin cancers. However, in the concentrated broccoli sprout group only half of them got skin cancers and they were about half the size of the placebo group’s (14). It’s interesting that it wasn’t used as a sunscreen but after sun exposure to reduce the UV’s damaging effects.

Broccoli sprouts nutrition

It’s tricky finding reliable information on the nutritional benefits of broccoli sprouts because you don’t often see them in the supermarket. Mostly, you’ll be able to buy them as supplements, but the fresh ones do have more nutrients than the supplements.

As a guide, though, a portion of 1.5 cups (about 3 ounces), you’ll find:

• 35 Kilocalories

• 5 g of carbohydrates

• 2 g of protein

• 0.5 g of fat

• They’re also rich in vitamins A and C, and in calcium, iron, manganese and fibre. And, of course, sulforophane.

So if you can’t buy the fresh sprouts easily, the best course of action is to grow your own and it’s much simpler than you might think.

How to grow broccoli sprouts

You’ll need a seed sprouting jar, or a glass jar that will hold about 2 cups. Seed sprouting jars have a drainer built into them, so if you’re using an ordinary glass jar you’ll need a piece of muslin or a similar cloth that you can attach with an elastic band to drain the water without losing your seeds.

You want to use non-GMO, non-hybrid, seeds that aren’t chemically treated, ideally, organic. Don’t try to grow too many at a time because they can go mouldy if they’re crowded or if you keep them too long.

These are the steps to follow:

1. Firstly, take about 1 tablespoon of seeds to grow 1 cup of sprouts and rinse them thoroughly in fresh water. I recommend filtered water. Then fill the jar to cover the seeds and soak them for about 12 hours at a temperature of 18-20° C. If your ambient temperature is higher, you won’t need to soak for as long.

2. Drain them well, using the strainer or the muslin lid. Then rinse them well with fresh water and leave them upside down in a bowl on a slant to allow the seeds to drain properly. They’re best grown out of direct sunlight. The kitchen bench is ideal.

3. Rinse them twice a day, or 3 times if the weather is warm. Drain well as in step 2 each time.

4. They should sprout within 3-4 days.

5. Once sprouted, keep them in the fridge to stop them going mouldy and use within a few days.

6. Enjoy them fresh in sandwiches, wraps and salads. They lose a lot of their nutrients if you cook them, but you can add them to a stir fry.

Brassicas contain other nutrients too that broccoli sprouts don’t have. I talk about them in more detail in my book. If you’d like to buy the book, click the button below.

References

1.         Atwell LL, Zhang Z, Mori M, et al. Sulforaphane bioavailability and chemopreventive activity in women scheduled for breast biopsy. Cancer Prevention Research. 2015;8(12):1184-1191. doi:10.1158/1940-6207.capr-15-0119

2.       Li Y, Zhang T, Korkaya H, et al. Sulforaphane, a dietary component of broccoli/broccoli sprouts, inhibits breast cancer stem cells. Clinical Cancer Research. 2010;16(9):2580-2590. doi:10.1158/1078-0432.ccr-09-2937

3.       Li Y, Buckhaults P, Li S, Tollefsbol TO. Temporal efficacy of a sulforaphane-based broccoli sprout diet in prevention of breast cancer through modulation of epigenetic mechanisms. Cancer Prevention Research. 2018;11(8):451-464. doi:10.1158/1940-6207.capr-17-0423

4.         Keum Y-S, Khor TO, Lin W, et al. Pharmacokinetics and pharmacodynamics of broccoli sprouts on the suppression of prostate cancer in transgenic adenocarcinoma of Mouse Prostate (tramp) mice: Implication of induction of Nrf2, HO-1 and apoptosis and the suppression of Akt-dependent kinase pathway. Pharmaceutical Research. 2009;26(10):2324-2331. doi:10.1007/s11095-009-9948-5

5.         Alumkal JJ, Slottke R, Schwartzman J, et al. A phase II study of sulforaphane-rich broccoli sprout extracts in men with recurrent prostate cancer. Investigational New Drugs. 2015;33(2):480-489. doi:10.1007/s10637-014-0189-z

6.         Yanaka A, Hyodo I, Yamamoto M. Daily Intake of sulphoraphane-rich broccoli sprouts prevents colon tumor formation in mice treated with dextran sodium sulfate and azoxymethane via stimulating NRF2-dependent antioxidant enzymes. Semantic Scholar. https://www.semanticscholar.org/paper/Daily-intake-of-sulphoraphane-rich-broccoli-sprouts-Yanaka-Hyodo/08af133801e8ecf24b52da7c7ec1ca449c3b7a6c. Published December 1, 2006. Accessed October 12, 2022.

7.         Yanaka A, Suzuki H, Mutoh M, et al. Chemoprevention against colon cancer by dietary intake of sulforaphane. Functional Foods in Health and Disease. 2019;9(6):392-411. doi:10.31989/ffhd.v9i6.607

8.       Conaway CC, Wang C-X, Pittman B, et al. Phenethyl isothiocyanate and sulforaphane and their N-acetylcysteine conjugates inhibit malignant progression of lung adenomas induced by tobacco carcinogens in A/J mice. Cancer Research. 2005;65(18):8548-8557. doi:10.1158/0008-5472.can-05-0237

9.       Egner PA, Chen J-G, Zarth AT, et al. Rapid and sustainable detoxication of airborne pollutants by broccoli sprout beverage: Results of a randomized clinical trial in China. Cancer Prevention Research. 2014;7(8):813-823. doi:10.1158/1940-6207.capr-14-0103

10.     Bauman JE, Zang Y, Sen M, et al. Prevention of carcinogen-induced oral cancer by sulforaphane. Cancer Prevention Research. 2016;9(7):547-557. doi:10.1158/1940-6207.capr-15-0290

11.     Munday R, Mhawech-Fauceglia P, Munday CM, et al. Inhibition of urinary bladder carcinogenesis by broccoli sprouts. Cancer Research. 2008;68(5):1593-1600. doi:10.1158/0008-5472.can-07-5009

12.       Abbaoui B, Riedl KM, Ralston RA, et al. Inhibition of bladder cancer by Broccoli isothiocyanates sulforaphane and erucin: Characterization, metabolism, and interconversion. Molecular Nutrition & Food Research. 2012;56(11):1675-1687. doi:10.1002/mnfr.201200276

13.     Jianguo C, Jian Z, Gaoren W, Groopman JD, Kensler TW. Qidong: A crucible for studies on liver cancer etiology and prevention. Cancer Biology & Medicine. 2019;16(1):24. doi:10.20892/j.issn.2095-3941.2018.0394

14.       Tuma RS. Broccoli sprout consumption reduces H. pylori colonization. Oncology Times. 2006;28(2):27-29. doi:10.1097/01.cot.0000294723.80359.ea