05 Feb Which Fruits and Vegetables Are Better For Lowering Blood Pressure?
MedicalResearch.com Interview with:
Lea Borgi, MD
Program in Nephrology
Brigham and Women’s/ Massachusetts General
Medical Research: What is the background for this study? What are the main findings?
Dr. Borgi: Hypertension is one of the most common diseases in the United States and in the world. It is a known risk factor for cardiovascular disease. Even when hypertension is well-controlled with anti-hypertensives, these individuals are at an increased cardiovascular risk. Therefore, a healthy lifestyle is critical for normotensive individuals. This usually includes dietary patterns. However, if we could restrict dietary patterns to specific foods, then we would be able to provide better advice to our patients.
In this study, we analyzed the association of fruits and vegetables with the incidence of hypertension. We were also interested in studying the change in consumption of fruits and vegetables over time and the incidence of hypertension. We used data from 3 large prospective cohort studies: the Nurses’ Health Study, the Nurses’ Health Study II and the Health Professional Follow-up study (total of 187,453 participants). Information about health and food intake was updated every 2 and 4 years, respectively.
We found that participants who consumed ≥4 servings/day of fruits (not including fruit juice) had a lower risk of developing hypertension (follow-up was more than 20 years), when compared to participants whose consumption was ≤4 servings/weeks (Hazard ratio=0.92; 95%CI= 0.87-0.97). However, the association of vegetable intake with hypertension was different; indeed, we found no significant association with a HR of 0.95(0.86-1.04).
To better understand these associations, we further analyzed individual fruits and vegetables with the incidence of hypertension. We found lower risks of developing hypertension when these individual fruits and vegetables were consumed ≥4 servings/week as compared to <1 serving/month: broccoli, carrots, tofu or soybeans, raisins and apples. In contrast, we found that eating more string beans or brussel sprouts was associated with an increased risk of hypertension with HRs of 1.11(1.05-1.17) and 1.23(1.04-1.46), respectively. In all of our analyses, we adjusted for potential cofounders (such as age, gender, body mass index and more).
Finally, we also found that increasing total fruit (but not total vegetable) consumption by ≥7servings/week in the preceding 8 years was associated with a lower risk of hypertension with a pooled HR 0.94(0.90-0.97).
Medical Research: What should clinicians and patients take away from your report?
Dr. Borgi: I would still recommend an increase in fruit and vegetable consumption to my patients. However, now I would emphasize slightly on the more frequent consumption of broccoli, carrots, tofu or soybeans, raisins and apples. Although we did observe and increased risk of hypertension with increasing string beans and brussel sprouts consumption, I think we still need more studies to better understand the mechanisms underlying these associations.
Medical Research: What recommendations do you have for future research as a result of this study?
Dr. Borgi: More epidemiological as well as physiological studies are needed to better understand the association of specific foods with hypertension and other chronic diseases.
Dr. Lea Borgi (2015). Which Fruits and Vegetables Are Better For Lowering Blood Pressure?