Dr. Collins reviews an excellent new study: “Plant Based Diets Are Associated with a Lower Risk of Incident Cardiovascular Disease, Cardiovascular Disease Mortality, and All Cause Mortality in a General Population of Middle Aged Adults” published in Journal of the American Heart Association on August 7, 2019.
Folks, science matters, and this research study is definitely one worthy of your attention. It is rare that superbly implemented, large cohort prospective studies on nutritional prevention for major diseases are performed. The cost of funding such studies is phenomenal and research is often funded by pharma companies hoping to secure FDA approval for salable treatments (rather than prevention). Veggies are less easily monetized than pharmaceuticals, so finding funding for expensive longitudinal study of nutritional intervention is the exception, rather than the rule. Kudos to Johns Hopkins University and the University of Minnesota School of Public Health for committing to this excellent and well powered study.
Reference: 7 Aug 2019|https://doi.org/10.1161/JAHA.119.012865|Journal of the American Heart Association. 2019; 8
The Study Design: A group of 12,168 middle-aged adults were followed from 1987 through 2017. Let me emphasize this study lasted THIRTY YEARS people! It takes tenacity, commitment and attention span to keep track of a group of 12,000 people over three decades, maintain regular follow up and data collection for THIRTY YEARS! Can I get a high five for these dedicated researchers!
Previous sizable prospective studies looking at outcomes of plant-based diet were done using the Seventh-Day Adventist community and other health-conscious groups and then compared with the general population “SAD” diet, or the “Standard American Diet.” Because study participants were pre-selected from communities which may practice other health promoting lifestyle activities at a higher rate than the general population, it was questioned whether the results were generalizable, or attributable to diet alone. To address this concern, in the Hopkins/UMinn study, the cohort were from four disparate US communities: Washington County Maryland; Forsyth County, North Carolina; Minneapolis, Minnesota; and Jackson, Mississippi. The participants comprised women and men between the ages of 45-64 at baseline (in 1987-89) and the initial enrollment was 15,792 participants. The study participants had six follow up visits over the thirty year study period. Visit one during time interval 1987 to 1989, visit two between 1990 and 1992, visit three between 1993 and 1995, visit four between 1996-1998, visit 5 was between 2011-2013 and the final visit occurred between 2016 and 2017.
Trained interviewers used a standardized food frequency questionnaire which quantified serving sizes and types and preparations of foods and beverages. The reliability of the food frequency questionnaire was separately validated. Participants’ responses were classified using four previously validated plant-based diet scores: Plant-based diet index (PDI), Healthy plant-based diet index (hPDI), Unhealthy plant-based-diet index (uPDI), and the pro-vegetarian diet index. Using four indexes to assess the cohort allowed a more complete and nuanced evaluation of the dietary habits than any one index alone would have provided.
Baseline information was collected regarding socio-demographics (age, gender, race/ethnicity and education level), smoking, exercise, alcohol intake, health diagnoses and medication use (lipid-lowering and antihypertensive medications among others). Participants’ BMI , lipid levels, blood sugar, kidney functions, and blood pressures were also tracked. Participants who had known cardiovascular disease at baseline were eliminated from the cohort.
Outcomes of cardiovascular disease events and death from cardiovascular or other (all) causes were monitored through annual phone calls with participants, surveillance of local hospital records and state death records. These were compared with the National Death Index for the study time period.
Study Results: I will quote the study authors directly as their summary was succinct. “In this community-based cohort of US adults without cardiovascular disease at baseline, we found that higher adherence to an overall plant-based diet or a provegetarian diet, diets that are higher in plant foods and lower in animal foods, was associated with a lower risk of incident cardiovascular disease, cardiovascular disease mortality, and all-cause mortality. Healthy plant-based diets, which were higher in whole grains, fruits, vegetables, nuts, legumes, tea, and coffee and lower in animal foods, were associated with a lower risk of cardiovascular disease mortality and all-cause mortality.”
Please read the study for yourself when time allows. It is worth your time and the methods and discussion are an interesting perspective on the many variables that are considered in this type of extensive investigation. A link to the original article is available here: https://www.ahajournals.org/doi/full/10.1161/JAHA.119.012865
You can find lots of plant-based recipe inspiration at our Apple a Day Doc online journal: https://appleadaydoc.com/blog/.
Written by: Ann C. Collins, MD, RYT
Toasted Quinoa with Summer Squash and Pistachios
