07 September, 2007

Diet and health

The long-term prognosis for breast cancer survivors continues to improve. Better treatment, adjuvant chemo- and hormonal therapies offer women an excellent outlook, especially if the disease is detected early.

In addition, support groups give psychological comfort, exercise seems to be beneficial, and now a large study has looked at diet and survival. Pierce et al (JAMA 2007;298:289-98) allocated women after early stage breast cancer care to either a diet very high in fruit, vegetables and fibre but low in fat or a comparison dietary pattern which recommended “5-A-Day” fruit and vegetables.

The “extra fruit, fibre 'n veg” with low fat did not make a difference to recurrence, metastases or all-cause mortality over a period of seven years. Perhaps if the control group had been given no dietary instructions, and gained weight, there might have been a difference but failing to advise women about diet would be considered unethical. Where patients gain weight by not balancing intake and expenditure, the prognosis is poorer, so energy balance may be more important than extreme diets (Grapstur & Khan pp 335-6).