How broccoli might protect the prostate
Publication Date:03/07/2008
There are plenty of good health reasons to eat up your greens. Now new research suggests that eating broccoli regularly can produce chemical changes in the body that might protect men against prostate cancer.
What do we know already?
Prostate cancer is the second most common cancer in men, after skin cancer. Although thousands of men die of the disease every year, it tends to a fairly slow-growing cancer. About 1 in 14 men will be diagnosed with prostate cancer, but only 1 in 25 will die of it. Prostate cancer is rare before the age of 50.
Some studies have suggested that green vegetables, such as spinach, cabbage and broccoli, could play a part in preventing prostate cancer. To find out how this might work, researchers have now used a type of genetic testing, looking for any chemical changes in the body that happen after eating broccoli regularly.
What does the new study say?
Researchers looked at 22 men who were at risk of developing prostate cancer. Some of them ate 400 grams (about 14 ounces) of steamed broccoli each week for a year. The rest ate the same amount of peas.
At the start of the study, then again after six and 12 months, the men had tissue samples taken from their prostates with a fine needle. These samples were tested for changes in gene activity.
The men who'd been eating broccoli had more changes in gene expression. Gene expression is how the information in a gene is 'read', and used to build useful substances in the body, like proteins. The researchers think that the changes they saw in gene expression could help protect against prostate cancer.
The study only looked at gene activity in men's bodies. It didn't look directly at whether eating broccoli could prevent prostate cancer.
Where does the study come from?
The researchers were based at the Institute of Food Research in Norwich. Their study appeared in PLoS ONE, a free online medical journal, published by the Public Library of Science. The study was paid for by the Biotechnology and Biological Sciences Research Council, a government body that supports scientific research.
How reliable are the findings?
The study only looked at 22 men, and not all of them were included in the final analysis, as some of the samples they gave didn't produce clear results.
The study is also a fairly early-stage piece of research, looking only at changes in gene activity. To find out if broccoli definitely prevents prostate cancer, you'd need a much larger study. It would need to compare a group of men who ate broccoli with a group who didn't, and to follow them for a long time to see whether they developed prostate cancer. No-one has done this kind of research yet.
What does this mean for me?
Based on this research, it's impossible to know what effect broccoli might have on your individual risk of prostate cancer. Your own risk of this disease will depend on other things, such as whether you have a family history of prostate cancer. However, we do know that a healthy diet includes plenty of fruit and vegetables. As a general rule, eating healthily can cut your risk of cancer and heart problems.
Broccoli is rich in vitamin C, iron, fibre and other nutrients. As long as you enjoy the taste, eating broccoli is unlikely to have any downsides. If you're not so keen on broccoli, then cauliflower, cabbage, rocket and watercress all contain similar nutrients. These foods all belong to the cruciferous group of vegetables.
The broccoli used in the study contained high amounts of a chemical called glucosinolate. But the researchers say that, after cooking and freezing, it would contain roughly the same nutrients as fresh broccoli from a supermarket.
What should I do now?
Prostate cancer mainly affects older men, with two-thirds of cases affecting men over 70. If you're worried about prostate cancer, talk to your doctor. He or she will be able to assess your risk, and may suggest a blood test to check for signs of cancer.
Many older men get an enlarged prostate. This can cause annoying symptoms, such as needing to urinate regularly. But it's not cancer, and doesn't usually lead to any serious health problems.
National guidelines recommend we all eat five portions of fruit and vegetables a day. You might want to include some broccoli in your diet. For more nutritious and tastier broccoli, it's best to cook it by steaming or stir-frying. But if you don’t like broccoli, you needn’t feel forced to eat it. You could try a similar vegetable like cabbage or cauliflower.
From:
Traka M, Gasper AV, Melchini A, et al. Broccoli consumption interacts with gstm1 to perturb oncogenic signalling pathways in the prostate. PLoS ONE 3(7): e2568 doi:10.1371/journal.pone.0002568
To read more, see our information on prostate cancer.
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This information does not replace medical advice. If you are concerned you might have a medical problem please ask your Boots pharmacy team in your local Boots store, or see your doctor.
