SAN ANTONIOA randomized dietary intervention study of
3,100 breast cancer survivors requires the study group to eat five vegetable
servings and 16 oz of vegetable juice daily, a level of vegetable intake that
has not previously been examined. By comparison, the women in the control group
are following the National Cancer Institute (NCI) diet, which includes only
three vegetable servings and no vegetable juice.
The Women’s Healthy Eating and Living (WHEL) study is
examining the effects of a diet rich in vegetables, fruit, and fiber on the
health of breast cancer survivors, including cancer recurrences.
Despite the high level of vegetables required, participants in
the study have been able to change their diet and maintain the change for more
than 4 years, said Vicky E. Jones, MD, associate professor of medicine,
University of California, San Diego, Cancer Center.
To confirm the dietary changes, investigators measured blood
compounds, including beta-carotene, alpha-carotene, and lutein levels.
"These blood levels substantiate that the participants are making major
changes in their vegetable intake, something that has not been accomplished in
any of the other dietary intervention studies to date," Dr. Jones said.
The study participants also completed food frequency
questionnaires and 24-hour dietary recalls, Dr. Jones said at a poster session
of the 23rd Annual San Antonio Breast Cancer Symposium.
"This population is very motivated," Dr. Jones told
ONI. Even before enrollment in the study, many of the women had already added
more vegetables and fruits to their diet to meet the NCI recommendations, she
said. The NCI daily diet includes two fruit servings, three vegetable servings,
20 g of fiber, and less than 30% of energy from fat. The WHEL diet requires
three fruit servings, five vegetable servings, 16 oz of vegetable juice, 30 g
of fiber, and 20% of energy from fat.
To encourage and promote the dietary changes, trained nutrition
counselors make regular phone calls to the study participants. The study also
sponsors cooking classes so that the women can learn new ways to prepare food
to meet their vegetable and fruit requirements.
Enrollment was opened in 1995 and completed Nov. 30, 2000, Dr.
Jones said. Eligible women had stage I (tumor 1 cm or larger), stage II, or
stage IIIA tumors; diagnosis within 4 years of randomization; and no current
To date, there have been approximately 200 relapses and 58
deaths. It is too early to evaluate outcome, she said.