Healthy, plant-rich diets help lower the risk of early death, new study confirms
Studies have generally focused on the life-promoting benefits of individual foods or food component.
(ONLINE) - Growing evidence confirms that dietary choices are key to maintaining health. Research increasingly indicates that unhealthy eating habits can lead to early, preventable deaths.
Until now, though, studies have generally focused on the life-promoting benefits of individual foods or food components.
Researchers at the Harvard T.H. Chan School of Public Health in Boston, MA, recently led a study to see how long-term eating patterns affect mortality risks.
These experts assessed adherence to diets that align with the current Dietary Guidelines for Americans, 2020-2025Trusted Source (DGAs). They then compared the results with other health data collected over 36 years from more than 100,000 people in two long-term national studies.
Corresponding author Dr. Frank Hu, Fredrick J. Stare professor of nutrition and epidemiology, and chair of the Department of Nutrition notes that “[t]he Dietary Guidelines for Americans are intended to provide science-based dietary advice that promotes good health and reduces major chronic diseases.”
“Thus, it is critical to examine the associations between DGAs-recommended dietary patterns and long-term health outcomes, especially mortality,” he adds.
The study findings appear in JAMA Internal Medicine.
The study methods
The Harvard researchers analyzed and combined results from the Nurses’ Health Study (NHS) and the Health Professionals Follow-up Study (HPFS).
The NHS, which began in 1976, tracked the health data of female nurses aged 30 to 55 years at baseline. The HPFS, which began in 1986, followed male health professionals aged 40-75.
Dr. Hu and his colleagues defined the baselines as 1984 for the NHS and 1986 for the HPFS, when questionnaires provided enough information to form dietary indices.
Their current work used data compiled from 75,230 NHS participants and 44,085 HPFS participants. All the individuals were free of cardiovascular disease or cancer when the study began.
At the baseline and every 2 to 4 years, the participants completed food frequency questionnaires (FFQs) covering over 130 food items every 2 to 4 years.
They also updated information regarding age, weight, body mass index (BMI), physical activity, smoking status, multivitamin use, menopausal status, and diagnosis of chronic diseases.
In the NHS, participants identified as Hispanic, non-Hispanic Black, non-Hispanic white, and “other.” The HPFS did not collect this information.
Comparing healthy diets
The researchers scored the data based on four dietary pattern indexes: Healthy Eating Index 2015 (HEI-2015), Alternate Mediterranean Diet (AMED), Healthful Plant-based Diet Index (HPDI), and Alternate Healthy Eating Index (AHEI).
All these diets share high consumption of vegetables, fruits, whole grains, nuts, and legumes. Some include animal-based foods while others eliminate them.
Higher scores on the indexes indicated greater compliance with the corresponding diet.
The study’s conclusions
Higher scores on at least one of the indexes also correlated with a reduced risk of premature death from all causes, and from cancer, cardiovascular disease, and respiratory diseases.
In the NHS and HPFS study populations, people with higher dietary scores were more likely to be older, nonsmokers, and more physically active. They also had a lower BMI.
Food choices and cancer
Kate Cohen, who was not involved in the present research, is a registered dietitian at the Ellison Clinic at St. John’s Health Center in Santa Monica, CA.
In an interview with Medical News Today, Cohen explained how diet can impact cancer development, saying: “We know that about half to two-thirds of cancers can be avoided through diet and lifestyle changes including staying at a healthy weight, increasing fruits and vegetables, limiting alcohol, and increasing dietary fiber.”
MNT also spoke about these findings with Dr. Monique Gary, a breast surgeon and the Medical Director of the Grand View Health/Penn Cancer Network cancer program. Dr. Gary was not involved in the study.
The oncologist shared that “[t]hese findings reinforce what we tell patients in oncology: that diet and lifestyle modification support all phases of cancer care and decrease [the] risk of recurrence and mortality.”