We should all eat plenty of vegetables as part of a healthy diet. For many cancer survivors, this is even more important, particularly for those who have been treated for bladder cancer, because beneficial molecules from certain vegetables can help prevent the cancer recurring.
However, just advising someone they should make changes to their diet is often not enough to bring about change in a lifelong habit of low vegetable consumption.
Supported by a grant from Cancer Research Trust NZ, Dr Michael Jameson of Waikato Hospital took part in a US-based study that successfully trialled a telephone-based dietary counselling service for bladder cancer survivors, in an effort to boost their vegetable intake. Says Dr Jameson, “Bladder cancer is common in New Zealand and usually responds well to treatment, especially in the 70% or so who have non-invasive disease. However, the cancer often returns within three years and more aggressive treatment is required.”
“Anything we can do to reduce recurrence greatly benefits the patient and the health service. There is mounting laboratory and clinical evidence that molecules in cruciferous* vegetables have potent anti-cancer activity, particularly a class of molecules called isothiocyanates. In the past, patients have been given literature promoting a healthy diet, and while this will have a positive effect, studies have shown that backsliding is common. Telephone diet counselling has proven successful in other situations, so we teamed up with groups in San Diego and Buffalo, New York, who were carrying out a pilot study in bladder cancer survivors.”
Half the participants were given print material promoting five servings of vegetable a day (controls), while the other half were provided with six months of structured telephone diet counselling and support.
Continues Dr Jameson, “Unlike patients in the control group, those in the phone counselling group significantly increased their total daily servings of vegetables, particularly cruciferous vegetables. Also, blood markers of vegetable consumption were significantly increased. So a very pleasing result, which will allow us to seek funding for a larger trial, where we can determine whether increased cruciferous vegetable consumption as a result of telephone diet counselling can reduce bladder cancer recurrence in the longer term.”
*Cruciferous vegetables include, broccoli, cabbage, cauliflower, bok choy, brussels sprouts and kale.