To conduct their study, the researchers evaluated three large cohorts—from the Nurses' Health Study (NHS), the Nurses' Health Study II (NHS II), and the Health Professionals Follow-up Study (HPFS)—of people who were free of chronic diseases and not obese at the start of the evaluation process. They measured specific lifestyle factors and weight gain every four years, with follow-up times ranging from 12 to 20 years.
One striking if somewhat predictable takeaway from the study is that focusing on overall dietary quality—such as eating less refined sugars and refined grains and more minimally processed foods—is probably more important to long-term health than monitoring total calorie or fat intake or other nutritional markers. As co-author Frank Hu, professor of nutrition and epidemiology at the Harvard School of Public Health, stated in a press release accompanying the announcement of the report, "The idea that there are no 'good' or 'bad' foods is a myth that needs to be debunked."
For more information on the report, you can watch the following video of the lead author, Dariush Mozaffarian, discussing the findings, or visit the Harvard School of Public Health's website.
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