(HOST) Commentator Rachel Johnson has been digging beneath the headlines to figure out what went wrong with the four-hundred-and-fifteen million dollar Women’s Health Study.
(JOHNSON) More than a decade ago, I stood in front of my class of nutrition students lecturing about the Women’s Health Initiative. I wanted them to be as excited as I was. This huge, four hundred fiftenn million dollar effort was planned to test the hypothesis that a low-fat diet rich in vegetables, fruits and grains would reduce heart disease as well as breast and colorectal cancer in women. I told my students that finally we were going to have the massive numbers we needed to get to the bottom of some women’s health issues. Beginning in the mid-1990s, scientists recruited over 48,000 women between the ages of fifty to seventy-nine and randomly assigned them to either a low-fat diet group, which received regular nutrition counseling, or to a control group, and followed their progress over time.
But when the Women’s Health Initiative researchers released their long-awaited findings earlier this year, the headlines screamed failure. My dietitian colleagues were stunned by the news that a low-fat, fruit-and vegetable-rich diet seemed to have no effect on the major killers of American women.
I wanted to dig beneath those disappointing headlines, so I called one of my former dietetic students. Elizabeth was a nutrition educator for the Women’s Health Initiative and based in Hawaii in the late ’90s. She taught the women to cut their fat intake to just twenty-two to twenty-eight grams per day. This is equal to about two Tablespoons of oil. She also taught them to get at least five servings of vegetables and fruit and at least six servings of grains every day. After hearing repeatedly how difficult it was to adhere to the diet, Elizabeth tried it herself. She told me, “I had the hardest time. I found the fat allotment way too low to sustain for more than a few days.”
In fact, relatively few women in the low-fat group met their dietary target; thirty-one percent of them at year one and only fourteen percent by year six. Clearly knowledge isn’t everything, and translating what we know into long lasting behavior change eludes many of us.
Was this trial a waste of time, asking women to aim for an impossible goal? I don’t think so. There were some intriguing findings when you tease out smaller subgroups of the women in the study. By digging deeper, it’s clear that the women who successfully made dietary changes did lower their risk of breast cancer and heart disease.
I love the science of nutrition. There’s always something new to be learned and I’m not ready to give up the conviction that we will eventually learn how to make it easier for people to live healthy lives. In the meantime, I’ll stick with what we nutrition experts do in fact agree on: exercise regularly, maintain a healthy weight, eat plenty of fruits and vegetables and whole grains, and watch the amounts and types of fat. I don’t expect any single future study to pronounce these the definitive answer to good health – but I look forward to the questions that’ll come up along the way.
Nutritionist Rachel Johnson is Dean of the College of Agriculture and Life Sciences at UVM and an advisor to EatingWell magazine.