The Effects of Chia Seed (Salvia hispanica L.) Consumption on Blood Pressure and Body Composition in Adults: A Systematic Review and Meta-analysis of Randomized Controlled Trials.

Purpose: Growing evidence has suggested that the consumption of chia seed can decrease blood pressure and obesity in adults. However, even studies have reported uncertain findings. The current meta-analysis aimed to assess the findings of randomized controlled trials (RCTs) on the efficacy of chia seed supplementation on blood pressure (systolic blood pressure [SBP], diastolic blood pressure [DBP]) and body composition (waist circumference [WC], weight, body mass index [BMI]) in adults.

Methods: A systematic search of the literature was carried out in the PubMed, Web of Knowledge, Scopus, Cochrane Central Library, and EMBASE from inception up to October 2024. Data were extracted and analyzed using a random-effects model, and reported as weighted mean differences (WMD) with 95% confidence intervals (CI).

Findings: A total of eight RCTs involving 372 participants were included in the meta-analysis. The results showed that chia consumption significantly reduced DBP (WMD: -7.49 mmHg; 95% CI: -9.64, -5.34; P < 0.001) and SBP (WMD: -5.61 mmHg; 95% CI: -8.77, -2.44; P = 0.001). Moreover, consuming chia seeds was linked to a notable decrease in WC (WMD: -1.46 cm; 95% CI: -2.68, -0.25; P = 0.01), but it had no significant effect on, BMI (WMD: -0.31 kg/m²; 95% CI: - 0.96, 0.34; P = 0.34) and weight (WMD: 0.09 kg; 95% CI: -0.76, 0.93; P = 0.84).

Implications: Chia consumption can significantly reduce SBP, DBP, and WC in adults, but no significant impact was showed on BMI and weight. To verify these results, more studies involving a greater number of participants are required.