Legume and soy consumption and the risk of hypertension: a systematic review and dose-response meta-analysis of prospective studies.

Background: Several studies have suggested that high intakes of legumes and soy products are associated with a lower risk of hypertension; however, the results have been inconsistent. We conducted a systematic review and meta-analysis to clarify the association between legumes and soy consumption and the risk of hypertension.

Methods: PubMed and Embase databases were searched up to 14 June 2025. Random effects models were used to calculate summary relative risks (RRs) and 95% confidence intervals (95% CIs) for the association between legume or soy consumption and hypertension risk. Heterogeneity was evaluated using I². The likelihood of causality was evaluated using World Cancer Research Fund (WCRF) criteria.

Results: 12 prospective studies were included in the meta-analysis. The summary RR for high versus low intake of legumes was 0.84 (95% CI 0.77 to 0.93, I²=65%, p_{heterogeneity}=0.003, n=10 studies, 86 098 cases, 309 853 participants) and for soy was 0.81 (95% CI 0.70 to 0.93, I²=82%, p_{heterogeneity}<0.0001, n=7 studies, 93 934 cases, 278 200 participants). In the linear dose-response analyses, the summary RR per 100 g/day was 0.88 (95% CI 0.80 to 0.97, I²=69%, p_{heterogeneity}=0.001, n=10) for legumes and 0.76 (95% CI 0.60 to 0.96, I²=89%, p_{heterogeneity}<0.0001, n=6) for soy. The test for non-linearity was not significant for legumes (p_{non-linearity}=0.13), suggesting a linear reduction in risk up to ~170 g/day, while for soy there was indication of non-linearity (p_{non-linearity}=0.01), and most of the reduction in risk was observed up to an intake around 60-80 g/day. Although there was an indication of publication bias with Egger's test (p=0.04) for legumes, this was explained by two outlying studies. Using WCRF criteria, the likelihood of causality was considered probable for both legumes and soy in relation to hypertension risk.

Conclusion: In this meta-analysis of 12 prospective cohort studies, legume and soy intakes were associated with lower risk of hypertension. These findings support dietary recommendations to increase the intake of legumes in the general population.