Five servings of fruits, vegetables per day may reduce mortality
Two servings of fruit and three servings of vegetables every day may be enough to reduce overall mortality and death from CVD, cancer and respiratory illness, according to research published in Circulation.
“While groups like the American Heart Association recommend four to five servings each of fruits and vegetables daily, consumers likely get inconsistent messages about what defines optimal daily intake of fruits and vegetables such as the recommended amount, and which foods to include and avoid,” Dong D. Wang, MD, ScD, epidemiologist, nutritionist and member of the medical faculty at Harvard Medical School and Brigham and Women’s Hospital, said in a press release.
For this analysis, researchers assessed 66,719 women from the Nurses’ Health Study (1984-2014) and 42,016 men from the Health Professionals Follow-up Study (1986-2014) with no CVD, cancer or diabetes at baseline. According to the study, diet was evaluated using a semiquantitative food frequency questionnaire updated from baseline every 2 to 4 years. In addition, researchers performed a dose-response meta-analysis that included data from the present study and 24 other prospective studies.
Benefits of fruits and vegetables
Researchers observed a nonlinear inverse relationship between fruit and vegetable consumption and overall mortality (P < .001); however, compared with two servings per day, intake of more than five servings per day was not associated with any further reduction beyond five servings per day:
- approximately three servings per day (HR = 0.95; 95% CI, 0.92-0.99; P < .001);
- approximately four servings per day (HR = 0.89; 95% CI, 0.86-0.92; P < .001);
- approximately five servings per day (HR = 0.88; 95% CI, 0.85–0.91; P < .001); and
- approximately seven servings per day (HR = 0.89; 95% CI, 0.86-0.93; P < .001), compared with just one serving per day.
Comparison with an intake of two servings per day, five servings of fruit and vegetables was associated with lower total mortality (HR = 0.87; 95% CI, 0.85-0.9), lower CVD mortality (HR = 0.88; 95% CI, 0.83-0.94), lower cancer mortality (HR = 0.9; 95% CI, 0.86-0.95) and lower respiratory disease mortality (HR = 0.65; 95% CI, 0.59-0.72).
In addition, total mortality did not decrease any further above approximately two servings of fruit per day compared with 0.5 servings per day (HR = 0.88; 95% CI, 0.86-0.91) and three servings of vegetables per day compared with 1.5 servings per day (HR = 0.94; 95% CI, 0.92-0.97), the researchers wrote.
“This amount likely offers the most benefit in terms of prevention of major chronic disease and is a relatively achievable intake for the general public,” Wang said in the release. “We also found that not all fruits and vegetables offer the same degree of benefit, even though current dietary recommendations generally treat all types of fruits and vegetables, including starchy vegetables, fruit juices and potatoes, the same.”
The association between fruit and vegetable intake and total mortality was consistent across various subgroups, including age, smoking, BMI, hypertension and hypercholesterolemia (P for all > .05).
Moreover, researchers found similar results following the dose-response meta-analysis that included 1,892,885 participants yielded similar results (RR for 5 servings per day vs. 2 servings per day = 0.87; 95% CI, 0.85-0.88; nonlinear P < .001).
“The American Heart Association recommends filling at least half your plate with fruits and vegetables at each meal,” Anne Thorndike, MD, MPH, chair of the AHA’s nutrition committee and associate professor of medicine at Harvard Medical School, said in the release. “This research provides strong evidence for the lifelong benefits of eating fruits and vegetables and suggests a goal amount to consume daily for ideal health. Fruits and vegetables are naturally packaged sources of nutrients that can be included in most meals and snacks, and they are essential for keeping our hearts and bodies healthy.”
The epidemic of unhealthy eating
In a related editorial that will be published in a future print issue of Circulation, Naveed Sattar, MD, PhD, professor of cardiovascular and medical sciences at the University of Glasgow, and Nita Forouhi, PhD, program leader and MRC investigator in nutritional epidemiology at the University of Cambridge, wrote that health professionals can “help people understand how to implement simple dietary changes. The biggest gains may come from encouraging those who rarely eat fruit or vegetables since diets rich in even modestly higher fruit and vegetable consumption are beneficial. Among the youngest children, the concept of repeated exposure has gained traction to train the palate to start enjoying fruit and vegetables. Adults can take up a similar ‘palate retraining challenge’ to learn to enjoy fruit and vegetables.
“The take-home point is that food is indeed medicine, and that health professionals and governments would do well to up their games to improve dietary intakes at individual and population levels,” the editorial authors wrote. “Increasing people’s enjoyment for and intakes of fruit and vegetables must be a key part of future dietary interventions. In the post-COVID world, where diets and other health behaviors have been adversely impacted due to lockdowns, more, not less, needs to be done to tackle the epidemic of unhealthy eating.”
- Sattar N, et al. Circulation. To appear in future print issue. Permission to use quotes granted by American Heart Association.