Food News Blues

All this coverage would be fine, perhaps even beneficial, if medical progress were as straightforward as it's often reported. Unfortunately, it's not. Headlines and sound bites can't capture the complexity of research. Science works in small steps, and failure and mistakes are an integral part of the process. Experiments flame out; hypotheses crash and burn. "Most science isn't a breakthrough," says Dr. Judah Folkman, the famed cancer researcher at Children's Hospital Boston who was involuntarily thrust into the spotlight by a 1998 New York Times story about his research. "It's incremental, brick by brick." But the public has big expectations. "Science and medicine have promised a lot," says Dr. Jerome Groopman of Harvard Medical School and a writer for The New Yorker. "We have all this technology, this information and resources, and we're making promises to people. In many cases, we still don't have the answers."

Published studies on the same topic can vary enormously in terms of sample size (small, medium, big), demographics (age, gender), data (self-reported versus objectively measured information) and length (weeks, months, years). Then there's the design of the study, a critical factor. The gold standard, a randomized, double-blind, placebo-controlled trial, is considered the most reliable because neither researchers nor participants know who is taking the medication being tested and who is taking the placebo (essentially a sugar pill).

Some studies, like the WHI, are prospective, which means a group of patients is watched from the beginning of a treatment, procedure or intervention. Others are retrospective: they look back at patient records to uncover hints about disease onset or patterns. Still others are "meta-analyses," overviews of existing studies on a similar theme. Even bad studies can get published in journals with less rigorous standards. "The media reports all studies as if they have the same degree of certainty," says Dr. Elias Zerhouni, director of the National Institutes of Health. "There's no real label of quality."

To really understand what's going on, you also have to follow the money. The government pays for much of basic science, but industries with a stake in the outcome often fund food and drug studies. An industry connection doesn't necessarily mean a study is wrong. Scientists have to rely on different sources of support in the increasingly ferocious battle for dollars. But, says Dr. Richard Deyo, professor of medicine at the University of Washington in Seattle, "when corporate sponsors fund research, it's more likely to show beneficial effects." For example, industry-funded studies have consistently concluded that soda can be part of a healthy diet. But non-industry studies find that sugary beverages contribute to obesity. The National Dairy Council pays for research on the link between dairy food and weight loss. The California Raisin Marketing Board underwrote a study showing that raisins fight oral bacteria. If raisins hadn't done the job, the public might never have known. Industry-funded studies with negative results are often not published.

The stars in this vast medical-research universe were perfectly aligned in the early 1990s, when the WHI began. Women's health advocates had been pushing for more research. The NIH had its first female director, Dr. Bernadine Healy. And there were serious questions about older women's health that needed answers. Observational studies, which follow people over time without intervening in their behavior, had suggested that estrogen might prevent heart disease; millions of women were urged to take it. Scientists also decided to study the role of a low-fat diet and the use of calcium and vitamin D supplements to protect against fractures from osteoporosis. Together, heart disease, breast cancer and osteoporosis represent major causes of death and disability in older women. Preventing these diseases could affect millions.

The WHI was a massive undertaking--the largest federally funded study of wom-en's health, ultimately costing $725 million over 15 years. In the early to mid-1990s, WHI researchers recruited 161,808 women age 50 to 79 from all over the country. This in itself was a major achievement because joining the study was a serious commitment. The women had to agree to be tested regularly, fill in lots of forms, take medication without knowing whether it would help them or hurt them, and, in the case of the dietary study, learn to cook and eat in a completely different way.