Abstract Body: Introduction: The DASH diet, along with increasing greens and beets, can help reduce blood pressure. While the benefits of DASH are well-established, much of the blood pressure-lowering effect of nitrate-rich foods comes from their ability to boost nitric oxide production. No prior study has looked at both approaches together. We formally reviewed research studies to see how the DASH diet and taking dietary nitrates affected blood pressure.
Hypothesis: Both the DASH diet and interventions with dietary nitrates lead to better blood pressure results than either one when applied separately, as the diet focuses on electrolyte management, and DASH and dietary nitrates utilise the nitrate, nitrite, and nitric oxide pathway to relax blood vessels.
Methods: We included studies in our review that examined changes in blood pressure due to the DASH dietary pattern or dietary nitrate interventions, as required by PRISMA. From all the studies we looked at, we included 17 studies that examined the effects of the DASH diet or dietary nitrate interventions (12 randomized controlled trials and 5 observational studies). Sections measuring systolic and diastolic blood pressure changes and hypertension incidence were studied. The Cochrane Risk of Bias tool was used to assess RCTs, while the Newcastle-Ottawa Scale was used to determine observational studies.
Results: When people with high blood pressure followed the DASH diet, systolic blood pressure was reduced by 5-10 mmHg from a reference diet. In contrast, less significant but important reductions occurred in people with normal blood pressure. Taking dietary nitrate, such as beetroot juice or nitrate-rich vegetables, produced average systolic BP decreases of 3 to 7 mmHg. Observational studies agreed with these results: individuals who ate a DASH-like diet or had high nitrate vegetable intake usually had better blood pressure and a lower chance of hypertension. Most of the RCTs were of high quality, but the observational evidence was of a moderate level.
Conclusions: Both the DASH diet and nitrate-rich foods appear to be effective in reducing high blood pressure. Our assessment points out that diet can be an important, non-medication way to control blood pressure. The results back efforts to use DASH diet recommendations in medical guidelines and include nitrate-rich vegetables for better hypertension management.