Other Name(s):

Brassica oleracea, Brassica Oleracea Italica Group, Brassica oleracea var. italica, Brocoli, Brócoli, Broccoli Flower, Calabrese, Purple Sprouting Broccoli.


Broccoli is a vegetable. The parts that grow above the ground are used to make medicine.

Broccoli is used for preventing cancer of the prostate, breast, colon, bladder, and stomach. Some people also use it for boosting the effectiveness of the immune system.

How does it work?

Chemicals in broccoli might have cancer-preventing and antioxidant effects.

Uses & Effectiveness

Possibly Effective for...

Insufficient Evidence to Rate Effectiveness for...

  • Bladder cancer. There is some evidence that eating 1.75 cups of broccoli or cabbage daily might lower the risk of developing bladder cancer by about 30%.
  • Breast cancer. There is some evidence that eating broccoli might modestly reduce younger women's risk of getting breast cancer. However, eating broccoli does not seem to help prevent breast cancer in older (postmenopausal) women.
  • Cancer of the colon and rectum. Some research suggests that eating broccoli might help prevent colorectal cancer.
  • Fibromyalgia. Early research suggests that taking ascorbigen and broccoli powder by mouth might reduce pain and other symptoms in people with fibromyalgia.
  • Prostate cancer. Some research suggests that eating broccoli and related vegetables, such as Brussels sprouts, cauliflower, and cabbage, might help to prevent prostate cancer. However, other research finds no link between eating these vegetables and lowering prostate cancer risk.
  • Stomach cancer. Some research suggests that eating broccoli might help to prevent stomach cancer.
  • Other conditions.
More evidence is needed to rate the effectiveness of broccoli for these uses.

Natural Medicines Comprehensive Database rates effectiveness based on scientific evidence according to the following scale: Effective, Likely Effective, Possibly Effective, Possibly Ineffective, Likely Ineffective, and Insufficient Evidence to Rate (detailed description of each of the ratings).


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Side Effects

Broccoli is LIKELY SAFE in the small amounts found in a normal diet. There's not enough information to know if broccoli is safe when taken in larger medicinal amounts.

When applied to the skin, broccoli can cause an allergic rash in hypersensitive people.

Special Precautions & Warnings

Pregnancy and breast-feeding: Broccoli is LIKELY SAFE for pregnant and breast-feeding women in food amounts. But larger medicinal amounts should be avoided until more is known.


Medications changed by the liver (Cytochrome P450 1A2 (CYP1A2) substrates)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Some medications are changed and broken down by the liver. Broccoli might increase how quickly the liver breaks down some medications. Taking broccoli along with some medications that are changed by the liver might decrease the effects and side effects of some medications. Before taking broccoli as a medicine, talk to your healthcare provider if you take any medications that are changed by the liver.

Some of these medications that are changed by the liver include clozapine (Clozaril), cyclobenzaprine (Flexeril), fluvoxamine (Luvox), haloperidol (Haldol), imipramine (Tofranil), mexiletine (Mexitil), olanzapine (Zyprexa), pentazocine (Talwin), propranolol (Inderal), tacrine (Cognex), theophylline, zileuton (Zyflo), zolmitriptan (Zomig), and others.

Medications changed by the liver (Cytochrome P450 2A6 (CYP2A6) substrates)Interaction Rating: Moderate Be cautious with this combination.Talk with your health provider.

Some medications are changed and broken down by the liver. Broccoli might increase how quickly the liver breaks down some medications. Taking broccoli along with some medications that are changed by the liver might decrease the effects and side effects of some medications. Before taking broccoli as a medicine, talk to your healthcare provider if you take any medications that are changed by the liver.

Some of these medications that are changed by the liver include nicotine, chlormethiazole (Heminevrin), coumarin, methoxyflurane (Penthrox), halothane (Fluothane), valproic acid (Depacon), disulfiram (Antabuse), and others.


Next to red peppers, you can get the most vitamin C from ________________. See Answer


The appropriate dose of broccoli depends on several factors such as the user's age, health, and several other conditions. At this time there is not enough scientific information to determine an appropriate range of doses for broccoli. Keep in mind that natural products are not always necessarily safe and dosages can be important. Be sure to follow relevant directions on product labels and consult your pharmacist or physician or other healthcare professional before using.

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Reviewed on 6/14/2021

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